Fragmentation of relativistic nuclei
International Nuclear Information System (INIS)
Cork, B.
1975-06-01
Nuclei with energies of several GeV/n interact with hadrons and produce fragments that encompass the fields of nuclear physics, meson physics, and particle physics. Experimental results are now available to explore problems in nuclear physics such as the validity of the shell model to explain the momentum distribution of fragments, the contribution of giant dipole resonances to fragment production cross sections, the effective Coulomb barrier, and nuclear temperatures. A new approach to meson physics is possible by exploring the nucleon charge-exchange process. Particle physics problems are explored by measuring the energy and target dependence of isotope production cross sections, thus determining if limiting fragmentation and target factorization are valid, and measuring total cross sections to determine if the factorization relation, sigma/sub AB/ 2 = sigma/sub AA/ . sigma/sub BB/, is violated. Also, new experiments have been done to measure the angular distribution of fragments that could be explained as nuclear shock waves, and to explore for ultradense matter produced by very heavy ions incident on heavy atoms. (12 figures, 2 tables)
Search for relativistic projectile fragments with charges 4/3, 5/3, 7/3, and 8/3
International Nuclear Information System (INIS)
Bloomer, M.A.; Friedlander, E.M.; Heckman, H.H.; Karant, Y.J.
1984-01-01
Recent speculation on the cause of the anomalously short reaction mean free paths of projectile fragmentation products (PF's) produced from relativistic heavy-ion (RHI) collisions with emulsion nuclei has led to the suggestion that nuclei with bound third-integral charges might be present among the PF's. The authors were thus motivated to search for such fractional charges among the 1 less than or equal to Z less than or equal to 3 PF's produced by the interactions of 1.88 GeV/nucleon 56 Fe nuclei in G-5 nuclear emulsion. Results show that all charge measurements for each PF are narrowly distributed around their integer means, and, with the possible exception of the set of measurements scattered around Z = 2.33, there is no indication that PF's of third-integral charge are produced with the same relative abundance as reported for anomalons to date, i.e., 2-6% for 3 less than or equal to Z less than or equal to 26
International Nuclear Information System (INIS)
Hines, D.F.; Frankel, N.E.
1979-01-01
The charged Bose has been previously studied as a many body problem of great intrinsic interest which can also serve as a model of some real physical systems, for example, superconductors, white dwarf stars and neutron stars. In this article the excitation spectrum of a relativistic spin-zero charged Bose gas is obtained in a dielectric response formulation. Relativity introduces a dip in the spectrum and consequences of this dip for the thermodynamic functions are discussed
Topology of White Stars in Relativistic Fragmentation of Light Nuclei
Andreeva, N P; Vokal, S; Vokalova, A; Gaitinov, A Sh; Gerassimov, S G; Goncharova, L A; Dronov, V A; Zarubin, P I; Zarubina, I G; Kovalenko, A D; Kravchakova, A; Larionova, V G; Levitskaja, O V; Lepehin, F G; Malakhov, A I; Moiseenko, A A; Orlova, G I; Peresadko, N G; Polukhina, N G; Rukojatkin, P A; Rusakova, V V; Salmanova, N A; Sarkisian, V R; Simonov, B B; Stan, E; Stanoeva, R; Chernyavsky, M M; Haidue, M; Kharlamov, S P; Tsakov, I; Shchedrina, T V
2004-01-01
In the present paper, experimental observation of the multifragmentation processes of light relativistic nuclei carried out by means of emulsions are reviewed. Events of the type of "white stars" in which the dissociation of relativistic nuclei is not accompanied by the production of mesons and the target-nucleus fragments are considered. A distinctive feature of the charge topology in the dissociation of the Ne, Mg, Si and S nuclei is an almost total suppression of the binary splitting of nuclei to fragments with charges higher than 2. The growth of the nuclear fragmentation degree is revealed in an increase in the multiplicity of singly and doubly charged fragments with decreasing charge of the main non-excited part of the fragmenting nucleus. The processes of dissociation of stable Li, Be, B, C, N, and O isotopes to charged fragments were used to study special features of the formation of systems consisting of the lightest nuclei - alpha, d and t. Clustering of the 3He nucleus can be detected in "white sta...
Momentum transfer in relativistic heavy ion charge-exchange reactions
Townsend, L. W.; Wilson, J. W.; Khan, F.; Khandelwal, G. S.
1991-01-01
Relativistic heavy ion charge-exchange reactions yield fragments (Delta-Z = + 1) whose longitudinal momentum distributions are downshifted by larger values than those associated with the remaining fragments (Delta-Z = 1, -2,...). Kinematics alone cannot account for the observed downshifts; therefore, an additional contribution from collision dynamics must be included. In this work, an optical model description of collision momentum transfer is used to estimate the additional dynamical momentum downshift. Good agreement between theoretical estimates and experimental data is obtained.
chi2 analyses of data on relativistic anomalous projectile fragments
International Nuclear Information System (INIS)
MacGregor, M.H.
1983-01-01
Nuclear emulsion data from four experimental groups are now available on the interactions of p relativistic anomalous projectile fragments. In the present paper we systematically combine these data together to form several different data sets, which are used to carry out a series of chi 2 parameter studies. The anomalous particle fragment component in the relativistic nuclear beam has been characterized previously in terms of the parameters f and lambda, where f is the anomalous particle fragment fraction in the secondary beam and lambda is the average anomalous particle fragment mean free path in the emulsion. We extend this result here by setting lambda = lambda 0 (2Z)/sup -beta/, where Z is the nuclear charge of the anomalous particle fragment, so that we can investigate the Z dependence of lambda. We also investigate isotopic effects in the equations used to describe ''normal'' secondary beam nuclei, and we examine the problem of optimizing the bin sizes used to represent the data. A series of (f,lambda 0 ,#betta#) parameter studies leads to the conclusion that the ''anomalous particle fragment effect'' exists for all Z values in the range Z = 3--26 included in the chi 2 analyses. These chi 2 analyses also indicate that #betta#>0, so that the anomalous particle fragment lambda's are Z dependent, but the data are not sufficient to pin down a definite value of #betta#. In order to assess the physical content of these results, we define a domain within which nuclear mean free paths can be accounted for by conventional nuclear forces (but not necessarily by conventional nuclear structure). The Z-dependent anomalous particle fragment mean free paths lie approximately on the boundary of this domain
Imaging of Nuclear Fragmentation in Nuclear Track Emulsion Relativistic Nuclei
International Nuclear Information System (INIS)
Zarubina, I.G. JINR
2011-01-01
The method of nuclear track emulsion provides a uniquely complete observation of multiple fragment systems produced in dissociation of relativistic nuclei. The most valuable events of coherent dissociation of nuclei in narrow jets of light and the lightest nuclei with a net charge as in the initial nucleus, occurring without the production of fragments of the target nuclei and mesons (the so-called w hite s tars), comprise a few percent among the observed interactions. The data on this phenomenon are fragmented, and the interpretation is not offered. The dissociation degree of light O, Ne, Mg and Si, and as well as heavy Au, Pb and U nuclei may reach a complete destruction to light and the lightest nuclei and nucleons, resulting in cluster systems of an unprecedented complexity. Studies with relativistic neutron-deficient nuclei have special advantages due to more complete observations. An extensive collection of macro videos of such interactions in nuclear track emulsion gathered by the Becquerel collaboration is presented
Relativistic charged fluids: hydrodynamic and kinetic approaches
International Nuclear Information System (INIS)
Debbasch, F.; Bonnaud, G.
1991-10-01
This report gives a rigorous and consistent hydrodynamic and kinetic description of a charged fluid and the basis equations, in a relativistic context. This study should lead to a reliable model, as much analytical as numerical, of relativistic plasmas which will appear in the interaction of a strong laser field with a plasma. For simplicity, we limited our study to a perfect fluid or, in other words, we disregarded the energy dissipation processes inside the fluid [fr
Fragmentation of Relativistic 56Fe Nuclei in Emulsion
International Nuclear Information System (INIS)
Chernov, G.M.; Gulamov, K.G.; Gulyamov, U.G.; Navotny, V.Sh.; Petrov, N.V.; Svechnikova, L.N.; Jakobsson, B.; Oskarsson, A.; Otterlund, I.
1983-03-01
Experimental data on general characteristics of projectile fragments in inelastic interactions of relativistic 56 Fe nuclei in emulsion (multiplicities, transverse momentum distributions, azimuthal correlations) are presented and discussed. A strong dependence on the mass number of the projectile nucleus is observed for the transverse momenta of the emitted projectile fragments. These fragments exhibit an azimuthal asymmetry caused by the transverse motion of the fragmenting residue, but it is shown that this motion can be responsible only for a part of the increase in the average transverse momentum of the fragments with increasing mass of the projectile. (author)
Neighbouring charge fragmentations in low energy fission
International Nuclear Information System (INIS)
Montoya, M.
1986-10-01
Shell and odd-even effects in fission have been largely studied until now. The structure in fragment mass, charge and kinetic energy distributions of fragments were interpreted as shell and even-odd effects. In this paper, we want to show that the discret change of fragment charge symmetry should produce also structures in those distribution. 19 refs
2002-01-01
In this experiment CR39 plastic nuclear track detectors will be used which are sensitive to detect relativistic nuclear fragments with charges Z@$>$5. They will be analyzed using an automatic track measuring system which was developed at the University of Siegen.\\\\ \\\\ This allows to measure large quantities of tracks in these passive detectors and to perform high statistics experiments. We intend to measure cross sections for the production of nuclear fragments from heavy ion beams at the SPS. \\\\ \\\\ The energy independence of the cross sections predicted by the idea of limiting fragmentation will be tested at high energies. In exposures with different targets we plan to analyze the factorization of the fragmentation cross sections into a target depending factor and a factor depending on the beam particle and the fragment. The cross sections for one proton remov Coulomb dissociation. \\\\ \\\\ We plan to investigate Coulomb dissociation for different targets and different energies. Fragment and projectile charges ...
Instability of extremal relativistic charged spheres
International Nuclear Information System (INIS)
Anninos, Peter; Rothman, Tony
2002-01-01
With the question 'Can relativistic charged spheres form extremal black holes?' in mind, we investigate the properties of such spheres from a classical point of view. The investigation is carried out numerically by integrating the Oppenheimer-Volkov equation for relativistic charged fluid spheres and finding interior Reissner-Nordstroem solutions for these objects. We consider both constant density and adiabatic equations of state, as well as several possible charge distributions, and examine stability by both a normal mode and an energy analysis. In all cases, the stability limit for these spheres lies between the extremal (Q=M) limit and the black hole limit (R=R + ). That is, we find that charged spheres undergo gravitational collapse before they reach Q=M, suggesting that extremal Reissner-Nordstroem black holes produced by collapse are ruled out. A general proof of this statement would support a strong form of the cosmic censorship hypothesis, excluding not only stable naked singularities, but stable extremal black holes. The numerical results also indicate that although the interior mass-energy m(R) obeys the usual m/R + as Q→M. In the Appendix we also argue that Hawking radiation will not lead to an extremal Reissner-Nordstroem black hole. All our results are consistent with the third law of black hole dynamics, as currently understood
International Nuclear Information System (INIS)
Drechsel, H.; Brechtmann, C.; Dreute, J.; Sonntag, S.; Trakowski, W.; Beer, J.; Heinrich, W.
1984-01-01
This paper describes an experiment measuring the interaction mean free paths for charge changing nuclear collisions of relativistic heavy ion fragments. We use a stack of CR39 plastic nuclear track detectors that was irradiated with 1.8 GeV/nucleon 40 Ar ions at the Berkeley Bevalac. About 1.5 x 10 7 etch cones were measured in this experiment using an automatic measuring system. By tracing the etch cones over successive plastic foils the particle trajectories in the stack were reconstructed. For 14185 trajectories with 6444 nuclear collisions of fragments with charge 9-15 the interaction mean free path in the plastic was determined. (orig.)
Bmad: A relativistic charged particle simulation library
International Nuclear Information System (INIS)
Sagan, D.
2006-01-01
Bmad is a subroutine library for simulating relativistic charged particle beams in high-energy accelerators and storage rings. Bmad can be used to study both single and multi-particle beam dynamics using routines to track both particles and macroparticles. Bmad has various tracking algorithms including Runge-Kutta and symplectic (Lie algebraic) integration. Various effects such as wakefields, and radiation excitation and damping can be simulated. Bmad has been developed in a modular, object-oriented fashion to maximize flexibility. Interface routines allow Bmad to be called from C/C++ as well as Fortran programs. Bmad is well documented. Every routine is individually annotated, and there is an extensive manual
Relativistic scattering theory of charged spinless particles
International Nuclear Information System (INIS)
Alt, E.O.; Hannemann, M.
1986-01-01
In the context of relativistic quantum mechanics the scattering is discussed of two and three charged spinless particles. The corresponding transition operators are shown to satisfy four-dimensional Lippmann-Schwinger and eight-dimensional Faddeev-type equations, respectively. A simplified model of two particles with Coulomb interaction can be solved exactly. Calculations have been made of (i) the partial wave S-matrix from which the bound state spectrum has been extracted; the latter agrees with a fourth-order result of Schwinger; (ii) the full scattering amplitude which in the weak-field limit coincides with the expression derived by Fried et al. from eikonalized QED. (author)
First spatial isotopic separation of relativistic uranium projectile fragments
International Nuclear Information System (INIS)
Magel, A.; Voss, B.; Armbruster, P.; Aumann, T.; Clerc, H.G.; Czajkowski, S.; Folger, H.; Grewe, A.; Hanelt, E.; Heinz, A.; Irnich, H.; Jong, M. de; Junghans, A.; Nickel, F.; Pfuetzner, M.; Roehl, C.; Scheidenberger, C.; Schmidt, K.H.; Schwab, W.; Steinhaeuser, S.; Suemmerer, K.; Trinder, W.; Wollnik, H.
1994-07-01
Spatial isotopic separation of relativistic uranium projectile fragments has been achieved for the first time. The fragments were produced in peripheral nuclear collisions and spatially separated in-flight with the fragment separator FRS at GSI. A two-fold magnetic-rigidity analysis was applied exploiting the atomic energy loss in specially shaped matter placed in the dispersive central focal plane. Systematic investigations with relativistic projectiles ranging from oxygen up to uranium demonstrate that the FRS is a universal and powerful facility for the production and in-flight separation of monoisotopic, exotic secondary beams of all elements up to Z=92. This achievement has opened a new area in heavy-ion research and applications. (orig.)
Relativistic effects and the fragmentation processes with the microscopic framework
International Nuclear Information System (INIS)
Maruyama, Tomoyuki
1995-01-01
We simulate the fragmentation processes in the Ca + Ca collisions at the bombarding energy 1.05 GeV/u using the Lorentz covariant RQMD and the non-covariant usual QMD approaches. The statistical decay calculation is connected to obtain the final state. By comparing the results of RQMD with those of QMD we examine the relativistic effects and show the necessity of the Lorentz covariance of the mean-field. (author)
2002-01-01
% EMU19 \\\\ \\\\ The collisions of heavy ions at relativistic energies have been studied to explore a number of questions related with hot and dense nuclear matter in order to extend our knowledge of nuclear equation-of-state. There are other aspects of these interactions which are studied to expound the process of projectile and/or target disintegrations. The disintegrations in question could be simply binary fissions or more complex processes leading to spallation or complete fragmentation. These important aspects of nuclear reactions are prone to investigations with nuclear track detectors. \\\\ \\\\One of the comparatively new track detector materials, CR-39, is sensitive enough to record particles of Z~$\\geq$~6 with almost 100\\% efficiency up to highly relativistic energies. The wide angle acceptance and exclusive measurements possible with plastic track detectors offer an opportunity to use them in a variety of situations in which high energy charged fragments are produced. The off-line nature of measuring tra...
Dual Fragment Impact of PBX Charges
Haskins, Peter; Briggs, Richard; Leeming, David; White, Nathan; Cheese, Philip; DE&S MoD UK Team; Ordnance Test Solutions Ltd Team
2017-06-01
Fragment impact can pose a significant hazard to many systems containing explosives or propellants. Testing for this threat is most commonly carried out using a single fragment. However, it can be argued that an initial fragment strike (or strikes) could sensitise the energetic material to subsequent impacts, which may then lead to a more violent reaction than would have been predicted based upon single fragment studies. To explore this potential hazard we have developed the capability to launch 2 fragments from the same gun at a range of velocities, and achieve impacts on an acceptor charge with good control over the spatial and temporal separation of the strikes. In this paper we will describe in detail the experimental techniques we have used, both to achieve the dual fragment launch and observe the acceptor charge response. In addition, we will describe the results obtained against PBX filled explosive targets; discuss the mechanisms controlling the target response and their significance for vulnerability assessment. Results of these tests have clearly indicated the potential for detonation upon the second strike, at velocities well below those needed for shock initiation by a single fragment.
Motions in the relativistic fields of a charged dust
International Nuclear Information System (INIS)
Fonseca Teixeira, A.F. da.
1980-04-01
The general relativistic motion of arbitrarily charged test particles is investigated, in the spherically symmetric fields of a charged, static, incoherent matter with T 0 0 = const. The condition for existence of stable circular orbits is established, inside and outside the diffused source. The null geodesics are also investigated, as a limiting case. (Author) [pt
Liouville equation of relativistic charged fermion
International Nuclear Information System (INIS)
Wang Renchuan; Zhu Dongpei; Huang Zhuoran; Ko Che-ming
1991-01-01
As a form of density martrix, the Wigner function is the distribution in quantum phase space. It is a 2 X 2 matrix function when one uses it to describe the non-relativistic fermion. While describing the relativistic fermion, it is usually represented by 4 x 4 matrix function. In this paper authors obtain a Wigner function for the relativistic fermion in the form of 2 x 2 matrix, and the Liouville equation satisfied by the Wigner function. this equivalent to the Dirac equation of changed fermion in QED. The equation is also equivalent to the Dirac equation in the Walecka model applied to the intermediate energy nuclear collision while the nucleon is coupled to the vector meson only (or taking mean field approximation for the scalar meson). Authors prove that the 2 x 2 Wigner function completely describes the quantum system just the same as the relativistic fermion wave function. All the information about the observables can be obtained with above Wigner function
Interaction of a relativistic charge with vacuum channel elements
International Nuclear Information System (INIS)
Tatarnikov, V.A.
1989-01-01
The problems of beam acceleration and transport require accounting for the effects connected with natural fields of charged particles. Flying along the accelerating structure elements the bunch induces charges and currents on the walls which, in their turn, affect the accelerating particles creating a secondary electromagnetic field. The effect of vacuum channel walls on the charged particle energy is considered. In the approximation of an assigned current the expressions for integral changes in the energy of relativistic charge, are obtained. The difference in the nature of charge interaction with the inhomogeneities of the diaphragm type and a semiinfinite waveguide, is shown
Large fragment production calculations in relativistic heavy-ion reactions
International Nuclear Information System (INIS)
Seixas de Oliveira, L.F.
1978-12-01
The abrasion-ablation model is briefly described and then used to calculate cross sections for production of large fragments resulting from target or projectile fragmentation in high-energy heavy-ion collisions. The number of nucleons removed from the colliding nuclei in the abrasion stage and the excitation energy of the remaining fragments (primary products) are calculated with the geometrical picture of two different models: the fireball and the firestreak models. The charge-to-mass dispersion of the primary products is calculated using either a model which assumes no correlations between proton and neutron positions inside the nucleus (hypergeometric distribution) or a model based upon the zero-point oscillations of the giant dipole resonance (NUC-GDR). Standard Weisskopf--Ewing statistical evaporation calculations are used to calculate final product distributions. Results of the pure abrasion-ablation model are compared with a variety of experimental data. The comparisons show the insufficiency of the extra-surface energy term used in the abrasion calculations. A frictional spectator interaction (FSI) is introduced which increases the average excitation energy of the primary products, and improves the results considerably in most cases. Agreements and discrepancies of the results calculated with the different theoretical assumptions and the experimental data are studied. Of particular relevance is the possibility of observing nuclear ground-state correlations.Results of the recently completed experiment of fragmentation of 213 Mev/A 40 Ar projectiles are studied and shown not to be capable of answering that question unambiguously. But predictions for the upcoming 48 Ca fragmentation experiment clearly show the possibility of observing correlation effects. 78 references
Strong-field relativistic processes in highly charged ions
Energy Technology Data Exchange (ETDEWEB)
Postavaru, Octavian
2010-12-08
In this thesis we investigate strong-field relativistic processes in highly charged ions. In the first part, we study resonance fluorescence of laser-driven highly charged ions in the relativistic regime by solving the time-dependent master equation in a multi-level model. Our ab initio approach based on the Dirac equation allows for investigating highly relativistic ions, and, consequently, provides a sensitive means to test correlated relativistic dynamics, bound-state quantum electrodynamic phenomena and nuclear effects by applying coherent light with x-ray frequencies. Atomic dipole or multipole moments may be determined to unprecedented accuracy by measuring the interference-narrowed fluorescence spectrum. Furthermore, we investigate the level structure of heavy hydrogenlike ions in laser beams. Interaction with the light field leads to dynamic shifts of the electronic energy levels, which is relevant for spectroscopic experiments. We apply a fully relativistic description of the electronic states by means of the Dirac equation. Our formalism goes beyond the dipole approximation and takes into account non-dipole effects of retardation and interaction with the magnetic field components of the laser beam. We predicted cross sections for the inter-shell trielectronic recombination (TR) and quadruelectronic recombination processes which have been experimentally confirmed in electron beam ion trap measurements, mainly for C-like ions, of Ar, Fe and Kr. For Kr{sup 30}+, inter-shell TR contributions of nearly 6% to the total resonant photorecombination rate were found. (orig.)
Quantum theory of relativistic charged particles in external fields
International Nuclear Information System (INIS)
Ruijsenaars, S.N.M.
1976-01-01
A study was made on external field theories in which the quantized field corresponds to relativistic elementary particles with non-zero rest mass. These particles are assumed to be charged, thus they have distinct antiparticles. The thesis consists of two parts. The first tries to accommodate the general features of theories of relativistic charged particles in external fields. Spin and dynamics in particular are not specified. In the second part, the results are applied to charged spin-1/2 and spin-0 particles, the dynamics of which are given by the Dirac resp. Klein-Gordon equation. The greater emphasis is on external fields which are rapidly decreasing, infinitely differentiable functions of space-time, but also considers time-independent fields. External fields, other than electromagnetic fields are also considered, e.g. scalar fields
Energy Technology Data Exchange (ETDEWEB)
Ogawa, T., E-mail: ogawa.tatsuhiko@jaea.go.jp [Research Group for Radiation Protection, Division of Environment and Radiation Sciences, Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, Shirakata-Shirane, Tokai, Ibaraki 319-1195 (Japan); Sato, T.; Hashimoto, S. [Research Group for Radiation Protection, Division of Environment and Radiation Sciences, Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, Shirakata-Shirane, Tokai, Ibaraki 319-1195 (Japan); Niita, K. [Research Organization for Information Science and Technology, Shirakata-shirane, Tokai, Ibaraki 319-1188 (Japan)
2013-09-21
The fragmentation cross-sections of relativistic energy nucleus–nucleus collisions were analyzed using the statistical multi-fragmentation model (SMM) incorporated with the Monte-Carlo radiation transport simulation code particle and heavy ion transport code system (PHITS). Comparison with the literature data showed that PHITS-SMM reproduces fragmentation cross-sections of heavy nuclei at relativistic energies better than the original PHITS by up to two orders of magnitude. It was also found that SMM does not degrade the neutron production cross-sections in heavy ion collisions or the fragmentation cross-sections of light nuclei, for which SMM has not been benchmarked. Therefore, SMM is a robust model that can supplement conventional nucleus–nucleus reaction models, enabling more accurate prediction of fragmentation cross-sections.
International Nuclear Information System (INIS)
Ogawa, T.; Sato, T.; Hashimoto, S.; Niita, K.
2013-01-01
The fragmentation cross-sections of relativistic energy nucleus–nucleus collisions were analyzed using the statistical multi-fragmentation model (SMM) incorporated with the Monte-Carlo radiation transport simulation code particle and heavy ion transport code system (PHITS). Comparison with the literature data showed that PHITS-SMM reproduces fragmentation cross-sections of heavy nuclei at relativistic energies better than the original PHITS by up to two orders of magnitude. It was also found that SMM does not degrade the neutron production cross-sections in heavy ion collisions or the fragmentation cross-sections of light nuclei, for which SMM has not been benchmarked. Therefore, SMM is a robust model that can supplement conventional nucleus–nucleus reaction models, enabling more accurate prediction of fragmentation cross-sections
Charge changing cross sections of relativistic uranium
International Nuclear Information System (INIS)
Gould, H.; Greiner, D.; Lindstrom, P.; Symons, T.J.M.; Crawford, H.; Thieberger, P.; Wegner, H.
1984-11-01
We report equilibrium charge state distributions of uranium at energies of 962 MeV/nucleon, 437 MeV/nucleon and 200 MeV/nucleon in low Z and high Z targets and the cross sections for U 92+ reversible U 91+ and U 91+ reversible U 90+ at 962 MeV/nucleon and 437 MeV/nucleon. Equilibrium thickness Cu targets produce approx. = 5% bare U 92+ at 200 MeV/nucleon and 85% U 92+ at 962 MeV/nucleon. 7 references, 5 figures
Charge changing cross sections of relativistic uranium
Energy Technology Data Exchange (ETDEWEB)
Gould, H; Greiner, D; Lindstrom, P; Symons, T J.M.; Crawford, H; Thieberger, P; Wegner, H
1985-05-15
We report equilibrium charge state distributions of uranium at energies of 962 MeV/nucleon, 437 MeV/nucleon and 200 MeV/nucleon in low Z and high Z targets and the cross sections for U/sup 92 +/reversibleU/sup 91 +/ and U/sup 91 +/reversibleU/sup 90 +/ at 962 MeV/nucleon and 437 MeV/nucleon. Equilibrium thickness Cu targets produce approx.=5% bare U/sup 92 +/ at 200 MeV/nucleon and 85% U/sup 92 +/ at 962 MeV/nucleon.
International Nuclear Information System (INIS)
Bauer, G.; Bieser, F.; Brady, F.P.; Chance, J.C.; Christie, W.F.; Gilkes, M.; Lindenstruth, V.; Lynen, U.; Mueller, W.F.J.; Romero, J.L.; Sann, H.; Tull, C.E.; Warren, P.
1997-01-01
A detector has been developed for the tracking and charge measurement of the projectile fragment nuclei produced in relativistic nuclear collisions. This device, MUSIC II, is a second generation Multiple Sampling Ionization Chamber (MUSIC), and employs the principles of ionization and time projection chambers. It provides unique charge determination for charges Z≥6, and excellent track position measurement. MUSIC II has been used most recently with the EOS (equation of state) TPC and other EOS collaboration detectors. Earlier it was used with other systems in experiments at the Heavy Ion Superconducting Spectrometer (HISS) facility at Lawrence Berkeley Laboratory and the ALADIN spectrometer at GSI. (orig.)
Charged-particle spectroscopy in the microsecond range following projectile fragmentation
Pfützner, M; Grzywacz, R; Janas, Z; Momayezi, M; Bingham, C; Blank, B; Chartier, M; Geissel, H; Giovinazzo, J; Hellström, M; Kurcewicz, J; Lalleman, A S; Mazzocchi, C; Mukha, I; Plettner, C; Roeckl, E; Rykaczewski, K; Schmidt, K; Simon, R S; Stanoiu, M; Thomas, J C
2002-01-01
We present a new approach to charged-particle spectroscopy of short-lived nuclei produced by relativistic projectile fragmentation. The system based on digital DGF-4C CAMAC modules and newly developed fast-reset preamplifiers was tested at the Fragment Separator of GSI. We were able to detect low-energy (approx 1 MeV) decay signals occurring a few microseconds after a heavy-ion implantation accompanied by a release of approx 1 GeV energy. Applications for the study of one- and two-proton radioactivity are discussed.
Charge-pickup of 238U at relativistic energies
International Nuclear Information System (INIS)
Rubehn, T.; Bassini, R.; Blaich, T.; Imme, G.; Iori, I.; Kunze, W.D.; Lindenstruth, V.; Lynen, U.; Moehlenkamp, T.; Moretto, L.G.; Ocker, B.; Pochodzalla, J.; Raciti, G.; Schuettauf, A.; Serfling, V.; Trautmann, W.; Trzcinski, A.; Verde, G.; Woerner, A.; Zude, E.; Zwieglinski, B.
1995-10-01
Cross sections for the charge-pickup of 238 U projectiles were measured at E/A=600 and 1000 MeV for seven different targets (Be, C, Al, Cu, In, Au and U). Events with two fission fragments with a sum charge of 93 in the exit channel were selected. Due to the significant excitation energy, the dominant part of produced Np nuclei fission instead of decaying to the ground state by evaporation. The observed cross sections can be well reproduced by intranuclear-cascade-plus-evaporation calculations and, therefore, confirm recent results that no exotic processes are needed to explain charge-pickup processes. (orig.)
Scattering of Non-Relativistic Charged Particles by Electromagnetic Radiation
Apostol, M.
2017-11-01
The cross-section is computed for non-relativistic charged particles (like electrons and ions) scattered by electromagnetic radiation confined to a finite region (like the focal region of optical laser beams). The cross-section exhibits maxima at scattering angles given by the energy and momentum conservation in multi-photon absorption or emission processes. For convenience, a potential scattering is included and a comparison is made with the well-known Kroll-Watson scattering formula. The scattering process addressed in this paper is distinct from the process dealt with in previous studies, where the scattering is immersed in the radiation field.
Collectivity in composite fragment emission from relativistic heavy ion collisions
International Nuclear Information System (INIS)
Bock, R.; Claesson, G.; Gutbrod, H.H.; Kolb, B.; Schmidt, H.R.; Doss, K.G.R.; Harris, J.W.; Kristiansson, P.; Lefebres, F.; Poskanzer, A.M.; Ritter, H.G.; Teitelbaum, L.; Tincknell, M.; Weiss, S.; Ferguson, R.L.; Gavron, I.; Jacak, B.V.; Wilhelmy, J.; Gustafsson, H.A.; Kampert, K.H.; Siemiarczuk, T.; Wieman, H.
1987-05-01
Composite fragments of 2< Z<10 have been measured in the Plastic Ball Spectrometer in 200 MeV/nucleon Au+Au and Au+Fe collisions. Strong azimuthal alignment of the fragments reveal the collective behaviour of the reaction. (orig.)
Real-time energy detector for relativistic charged particles
International Nuclear Information System (INIS)
Piestrup, A.
1988-01-01
The objective of the research is to investigate the use of coherent transition radiation to measure the energy of ultra-relativistic charged particles. The research has possible applications for the detection and identification of these particles. It can also be used for beam diagnostics for both high-repetition-rate and single-pulse, high-current accelerators. The device is low cost and can operate in situ while causing little or no perturbation to the beam. Three such coherent radiators have been constructed and tested at two accelerators using electron beam energies ranging from 50 to 228 MeV. Soft x-ray emission (1 keV to 4 keV) was emitted in a circularly symmetrical annulus with half-angle divergence of 2.5 to 9.0 mr. By selecting foil thickness and spacing, it is possible to design radiators whose angle of emission varies radically over a range of charge-particle energies
International Nuclear Information System (INIS)
Dersch, G.; Beckmann, R.; Feige, G.
1985-01-01
The interaction properties of projectile fragments from the fragmentation of 0.9 GeV/nucleon and 1.8 GeV/nucleon 40 Ar with Cu have been studied using radioactivation techniques. In this experiment, two identical copper blocks, 1 cm thick and 8 cm in diameter, are irradiated by relativistic projectiles in different configurations. In configuration 0, the blocks are touching while in configuration 10 or 20, the blocks are separated by 10 or 20 cm of air, respectively. It is assumed that when the relativistic projectiles interact with the first block of each pair, projectile fragments are created which interact with other nuclei in the first and second blocks. What is measured is the ratio of some target fragment activity, such as 24 Na or 28 Mg, produced in the second block relative to the first block, R
Universality of spectator fragmentation at relativistic bombarding energies
International Nuclear Information System (INIS)
Schuettauf, A.; Woerner, A.
1996-06-01
Multi-fragment decays of 129 Xe, 197 Au, and 238 U projectiles in collisions with Be, C, Al, Cu, In, Au, and U targets at energies between E/A=400 MeV and 1000 MeV have been studied with the ALADIN forward-spectrometer at SIS. By adding an array of 84 Si-CsI(Tl) telescopes the solid-angle coverage of the setup was extended to θ lab =16 . This permitted the complete detection of fragments from the projectile-spectator source. The dominant feature of the systematic set of data is the Z bound universality that is obeyed by the fragment multiplicities and correlations. These observables are invariant with respect to the entrance channel if plotted as a function of Z bound , where Z bound is the sum of the atomic numbers Z i of all projectile fragments with Z i ≥2. No significant dependence on the bombarding energy nor on the target mass is observed. The dependence of the fragment multiplicity on the projectile mass follows a linear scaling law. The reasons for and the limits of the observed universality of spectator fragmentation are explored within the realm of the available data and with model studies. It is found that the universal properties should persist up to much higher bombarding energies than explored in this work and that they are consistent with universal features exhibited by the intranuclear cascade and statistical multifragmentation models. (orig.)
Anisotropy in highly charged ion induced molecule fragmentation
International Nuclear Information System (INIS)
Juhasz, Z.; Sulik, B.; Fremont, F.; Chesnel, J.Y.; Hajaji, A.
2006-01-01
Complete text of publication follows. Studying fragmentation processes of biologically relevant molecules due to highly charged ion impact is important to understand radiation damage in biological tissues. Energy spectra of the charged molecule fragments may reveal the different fragmentation patterns meanwhile the angular distributions of the fragments characterize the dependence of fragmentation probability on the initial orientation of the molecule. The research to explore the angular distribution of the molecule fragments has only recently been started[1]. In 2006 we performed measurements at ARIBE facility at GANIL, Caen (France), in order to investigate orientation effects in molecule fragmentation. Fragmentation of H 2 O, C 6 H 6 and CH 4 , which represent different level of symmetry, have been studied by 60 keV N 6+ ion impact. Energy spectra of the charged fragments at different observation angles have been taken. As our example spectra show the different protonic peaks can be attributed to different fragmentation processes. Significant anisotropy can be seen in the different processes. The strongest evidence for the anisotropy can be seen in the spectra of C 6 H 6 , where the spectra appear isotropic in almost the whole observed energy range except one peak, which has a strong angular dependence and is maximal around 90 deg. (author)
Charge distribution in the ternary fragmentation of {sup 252}Cf
Energy Technology Data Exchange (ETDEWEB)
Senthil Kannan, M.T.; Balasubramaniam, M. [Bharathiar University, Department of Physics, Coimbatore (India)
2017-08-15
We present here, for the first time, a study on ternary fragmentation charge distribution of {sup 252}Cf using the convolution integral method and the statistical theory. The charge distribution for all possible charge combinations of a ternary breakup are grouped as a bin containing different mass partitions. Different bins corresponding to various third fragments with mass numbers from A{sub 3} = 16 to 84 are identified with the available experimental masses. The corresponding potential energy surfaces are calculated using the three cluster model for the two arrangements A{sub 1} + A{sub 2} + A{sub 3} and A{sub 1} + A{sub 3} + A{sub 2}. The ternary fragmentation yield values are calculated for the ternary combination from each bin possessing minimum potential energy. The yields of the resulting ternary combinations as a function of the charge numbers of the three fragments are analyzed for both the arrangements. The calculations are carried out at different excitation energies of the parent nucleus. For each excitation energy the temperature of the three fragments are iteratively computed conserving the total energy. The distribution of fragment temperatures corresponding to different excitation energies for some fixed third fragments are discussed. The presence of the closed shell nucleus Sn in the favourable ternary fragmentation is highlighted. (orig.)
Fragment emission in relativistic heavy-ion reactions
International Nuclear Information System (INIS)
Csernai, L.P.; Subramanian, P.R.; Buchwald, G.; Graebner, G.; Rosenhauer, A.; Maruhn, J.A.; Greiner, W.
1982-05-01
The authors present a theoretical description of nuclear collisions which consists of a three-dimensional fluid-dynamical model, a chemical equilibrium break-up calculation for local light fragment (i.e. p, n, d, t, 3 He, 4 He) production and a final thermal evaporation of these particles. The light fragment cross section and some properties of the heavy target residues are calculated for the asymmetric systems Ne+U at 400 MeV/N, Ne+Pb at 800 MeV/N and C+Sn at 86 MeV/N. The results of the model calculations are compared with recent experimental data. Several observable signs of the collective hydrodynamical processes are consistent with the present data. An event-by-event analysis of the flow patterns of the various clusters is proposed which can yield deeper insight into collision dynamics. (author)
International Nuclear Information System (INIS)
Milkau, T.U.E.
1991-11-01
For the study of the emission of medium-heavy fragments in asymmetric heavy ion collisions a series of experiments was performed and thereby following systems at intermediate and relativistic incident energies studied: 84 Kr+ 197 Au at E/A=35 MeV, 40 Ar+ 197 Au at E/A=30 MeV, respectively 220 MeV, and 12 C+ 197 Au at E/A=99 MeV, 301 MeV, 601 MeV, respectively 1105 MeV. In the experiments highly resolving detector telescopes with low thresholds were applied to the measurement of the energy and angular distributions of the medium-heavy fragments. The spectra were analyzed in the picture of longitudinally moving sources. Thereby beyond the production cross sections the angular distributions, the decreasement parameters in the high-energetic region of the energy spectra, and the position of the maxima were determined as characteristic parameters. The following picture resulted: The production cross sections for medium-heavy fragments showed a steep increasement and then a saturation, but with a strong projectile dependence. The charge distributions could be described by a power law, the parameter of which showed a universal dependence on the total incident energy. In the angular distributions the transition from an anisotropic emission at low energies to an isotropic emission from a nearly resting source at relativistic energies was distinctly to be recognized. The decreasement parameters of the energy distribution increased - for different projectiles differently strongly - logarithmically with growing incident energy. And the maxima of the energy distribution travelled with growing incident energy to smaller and smaller fragment energies. From this systematics a schematic model of the fragmentation can be obtained. (orig./HSI) [de
International Nuclear Information System (INIS)
Nilsen, B.S.; Waddington, C.J.; Cummings, J.R.; Garrard, T.L.; Klarmann, J.
1995-01-01
With the addition of krypton and silver projectiles we have extended our previous studies of the fragmentation of heavy relativistic nuclei in targets ranging in mass from hydrogen to lead. These projectiles were studied at a number of discrete energies between 450 and 1500A MeV. The total and partial charge-changing cross sections were determined for each energy, target, and projectile, and the values compared with previous predictions. A new parametrization of the dependence of the total charge-changing cross sections on the target and projectile is introduced, based on nuclear charge radii derived from electron scattering. We have also parametrized the energy dependence of the total cross sections over the range of energies studied. New parameters were found for a previous representation of the partial charge-changing cross sections in hydrogen and a new parametrization has been introduced for the nonhydrogen targets. The evidence that limiting fragmentation has been attained for these relatively light projectile nuclei at Bevalac energies is shown to be inconclusive, and further measurements at higher energies will be needed to address this question
International Nuclear Information System (INIS)
Bogatin, V.I.; Ganza, E.A.; Lozhkin, O.V.; Murin, Yu.A.; Oplavin, V.S.; Perfilov, N.A.; Yakovlev, Yu.P.
1981-01-01
An experimental investigation of inclusive characteristics of nuclei-target fragmentation is conducted for further development and test of physical value of the earlier suggested nuclear fragmentation model based on the connection of the fragmentation with fluctuations of the quasiparticle density in the two-component quantum liquid, an experimental investigation of the inclusive characteristics of the nuclei-target fragmentation is carried out. The processes of sup(3, 4, 6, 8)He and sup(6, 7, 8, 9, 11)Li fragment formation during the interaction of relativistic protons (Esub(p)=6.7 GeV) and deutrons (Esub(d)=3.1 GeV) with 112 Sn and 124 Sn isotopes are studied by the method of semiconductive ΔE-E detectors. Differential energy spectra of fragments and isotopic ratio of cross sections of their formation as well as data on the dependence of isotopic ratios of fragmentation cross sections on the energy of incident particles and on the fragment energy are obtained. Presented is a phenomenological model of fragmentation within the frames of which the obtained experimental data are analyzed [ru
Energy Technology Data Exchange (ETDEWEB)
Loveland, W.D.
1991-08-01
The work described herein is part of a project involving the study of low energy (< 10 MeV/A), intermediate energy (10--100 MeV/A) and relativistic (> 250 MeV/A) heavy ion reactions. In the low energy regime, we published a monograph on the properties of the heaviest elements and used that publication as a basis for making a set of best'' semi-empirical predictions of heavy element decay properties. The intermediate energy research effort focussed upon the completion of studies already begun and the initiation of a number of new experiments. In our study of a interaction of 21 MeV/nucleon {sup 129}Xe with {sup 197}Au, we compared the characteristics of the observed deep inelastic phenomena with various models of dissipative reactions and found significant discrepancies between observations and predictions. These discrepancies seemed to be caused by an improper treatment of pre-equilibrium in the early stages of the collision. In our study of the relativistic interaction of 400 MeV/nucleon {sup 12}C with {sup 197}Au, we reported the first direct physical measurement of the properties of the spallation residues from a nucleus-nucleus collision. We found the residue energies to be much lower than those predicted by the intranuclear cascade model, indicating some substantial modifications of that model are needed. But, we also found, indications of significant, non-zero values of the residue transverse momentum, a finding that calls into question the interpretation of a number of radiochemical recoil studies of the kinematics of high energy reactions. A program of performing numerical simulations of intermediate and high energy nuclear collisions using the QMD model was initiated.
Study of projectile fragments charge distribution at relativistic energy
International Nuclear Information System (INIS)
Pathak, Ramji; Singh, M.K.; Singh, V.
2012-01-01
Nuclear emulsion detector (NED) is one of the oldest detector technologies and has been in use from the birth of the experimental nuclear and astroparticle physics. Fortunately, it is a unique and simple detector till today, due to very high position resolution of the order of < 1μm along with several unique features. Nuclear emulsion detector has 4π detection capability with grain density of 300 to 500 grains per mm, compactness of the size and large range of ionization sensitivity depends upon the nature and need of the experiment. The high resolution allows easy detection of short-lived particles like the lepton or charmed mesons
Relativistic space-charge-limited current for massive Dirac fermions
Ang, Y. S.; Zubair, M.; Ang, L. K.
2017-04-01
A theory of relativistic space-charge-limited current (SCLC) is formulated to determine the SCLC scaling, J ∝Vα/Lβ , for a finite band-gap Dirac material of length L biased under a voltage V . In one-dimensional (1D) bulk geometry, our model allows (α ,β ) to vary from (2,3) for the nonrelativistic model in traditional solids to (3/2,2) for the ultrarelativistic model of massless Dirac fermions. For 2D thin-film geometry we obtain α =β , which varies between 2 and 3/2, respectively, at the nonrelativistic and ultrarelativistic limits. We further provide rigorous proof based on a Green's-function approach that for a uniform SCLC model described by carrier-density-dependent mobility, the scaling relations of the 1D bulk model can be directly mapped into the case of 2D thin film for any contact geometries. Our simplified approach provides a convenient tool to obtain the 2D thin-film SCLC scaling relations without the need of explicitly solving the complicated 2D problems. Finally, this work clarifies the inconsistency in using the traditional SCLC models to explain the experimental measurement of a 2D Dirac semiconductor. We conclude that the voltage scaling 3 /2 <α <2 is a distinct signature of massive Dirac fermions in a Dirac semiconductor and is in agreement with experimental SCLC measurements in MoS2.
A multiple sampling ionization chamber (MUSIC) for measuring the charge of relativistic heavy ions
International Nuclear Information System (INIS)
Christie, W.B.; Romero, J.L.; Brady, F.P.; Tull, C.E.; Castaneda, C.M.; Barasch, E.F.; Webb, M.L.; Drummond, J.R.; Sann, H.; Young, J.C.
1987-01-01
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 40 Ar and 0.30e fwhm for 1.08 GeV/nucleon 139 La and 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 σ≅100 μm. (orig.)
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.
International Nuclear Information System (INIS)
Loveland, W.D.
1991-08-01
The work described herein is part of a project involving the study of low energy ( 250 MeV/A) heavy ion reactions. In the low energy regime, we published a monograph on the properties of the heaviest elements and used that publication as a basis for making a set of ''best'' semi-empirical predictions of heavy element decay properties. The intermediate energy research effort focussed upon the completion of studies already begun and the initiation of a number of new experiments. In our study of a interaction of 21 MeV/nucleon 129 Xe with 197 Au, we compared the characteristics of the observed deep inelastic phenomena with various models of dissipative reactions and found significant discrepancies between observations and predictions. These discrepancies seemed to be caused by an improper treatment of pre-equilibrium in the early stages of the collision. In our study of the relativistic interaction of 400 MeV/nucleon 12 C with 197 Au, we reported the first direct physical measurement of the properties of the spallation residues from a nucleus-nucleus collision. We found the residue energies to be much lower than those predicted by the intranuclear cascade model, indicating some substantial modifications of that model are needed. But, we also found, indications of significant, non-zero values of the residue transverse momentum, a finding that calls into question the interpretation of a number of radiochemical recoil studies of the kinematics of high energy reactions. A program of performing numerical simulations of intermediate and high energy nuclear collisions using the QMD model was initiated
Excess Charge for Pseudo-relativistic Atoms in Hartree-Fock Theory
DEFF Research Database (Denmark)
Dall'Acqua, Anna; Solovej, Jan Philip
2010-01-01
We prove within the Hartree-Fock theory of pseudo-relativistic atoms that the maximal negative ionization charge and the ionization energy of an atom remain bounded independently of the nuclear charge $Z$ and the fine structure constant $\\alpha$ as long as $Z\\alpha$ is bounded.......We prove within the Hartree-Fock theory of pseudo-relativistic atoms that the maximal negative ionization charge and the ionization energy of an atom remain bounded independently of the nuclear charge $Z$ and the fine structure constant $\\alpha$ as long as $Z\\alpha$ is bounded....
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.
Na, D.-Y.; Moon, H.; Omelchenko, Y. A.; Teixeira, F. L.
2018-01-01
Accurate modeling of relativistic particle motion is essential for physical predictions in many problems involving vacuum electronic devices, particle accelerators, and relativistic plasmas. A local, explicit, and charge-conserving finite-element time-domain (FETD) particle-in-cell (PIC) algorithm for time-dependent (non-relativistic) Maxwell-Vlasov equations on irregular (unstructured) meshes was recently developed by Moon et al. [Comput. Phys. Commun. 194, 43 (2015); IEEE Trans. Plasma Sci. 44, 1353 (2016)]. Here, we extend this FETD-PIC algorithm to the relativistic regime by implementing and comparing three relativistic particle-pushers: (relativistic) Boris, Vay, and Higuera-Cary. We illustrate the application of the proposed relativistic FETD-PIC algorithm for the analysis of particle cyclotron motion at relativistic speeds, harmonic particle oscillation in the Lorentz-boosted frame, and relativistic Bernstein modes in magnetized charge-neutral (pair) plasmas.
Langevin description of fission fragment charge distribution from excited nuclei
Karpov, A V
2002-01-01
A stochastic approach to fission dynamics based on a set of three-dimensional Langevin equations was applied to calculate fission-fragment charge distribution of compound nucleus sup 2 sup 3 sup 6 U. The following collective coordinates have been chosen - elongation coordinate, neck-thickness coordinate, and charge-asymmetry coordinate. The friction coefficient of charge mode has been calculated in the framework of one-body and two-body dissipation mechanisms. Analysis of the results has shown that Langevin approach is appropriate for investigation of isobaric distribution. Moreover, the dependences of the variance of the charge distribution on excitation energy and on the two-body viscosity coefficient has been studied
Projectile fission of 238U relativistic ions in a Pb target and discovery of new fission fragments
International Nuclear Information System (INIS)
Bernas, M.; Donzaud, C.; Dessagne, Ph.; Miehe, Ch.; Hanelt, E.; Heinz, A.
1994-01-01
With the 238 U beam accelerated at relativistic energies by the heavy ion synchrotron (SIS) at GSI, fission was investigated using inverse kinematics. This geometry is well suited for analyzing fragments with the fragment separator. The fragments are identified by in flight measurements of their energy loss and time of flight signals. More than forty new isotopes have been discovered focusing on the light branch of fission products. (K.A.) 12 refs., 5 figs., 1 tab
The dispersion relation of charge and current compensated relativistic electron beam-plasma system
International Nuclear Information System (INIS)
Vrba, P.; Schroetter, J.; Jarosova, P.; Koerbel, S.
1978-01-01
The unstable regions of relativistic electron beam-plasma system were determined by analysing the general dispersion relation numerically. The external parameters were varied to ensure more effective instability excitations. The full charge- and current compensation presumptions lead to the new synchronism predictions. The slow space charge wave and slow cyclotron wave of the return current are synchronous with the plasma ion wave. (author)
Infinite stochastic acceleration of charged particles from non-relativistic initial energies
International Nuclear Information System (INIS)
Buts, V.A.; Manujlenko, O.V.; Turkin, Yu.A.
1997-01-01
Stochastic charged particle acceleration by electro-magnetic field due to overlapping of non-linear cyclotron resonances is considered. It was shown that non-relativistic charged particles are involved in infinitive stochastic acceleration regime. This effect can be used for stochastic acceleration or for plasma heating by regular electro-magnetic fields
K-Vacancy Production in the Collision of Highly Charged Relativistic Ions With Heavy Atoms
KHABIBULLAEV, P. K.
2014-01-01
A general expression for the cross section of the inelastic collision of relativistic highly charged ion with heavy (relativistic) atoms is obtained using the generalized eikonal approximation. In the ultrarelativistic limit, the obtained formula coincides with a known exact one. As an application of the obtained result, probability and cross section of the K-vacany production in the U92+ - U91+ collision are calculated.
International Nuclear Information System (INIS)
Morel, P.
1992-02-01
Relativistic heavy ion collisions present the opportunity of creating in laboratory small volumes of hot, dense nuclear matter. On the experimental point of view, the collision events are characterized by a great number of fragments, especially in the direction of the projectile. The first part is devoted to a survey of relativistic heavy ion physics. Then, we present two experimental set-ups which permit, in particular, the analyse of light fragment production at small angles. We present experimental results concerning light projectiles on Ca, Nb, Pb targets, with energies from 200 A.MeV up to 600 A.MeV. Different aspects of the collision are put in evidence. Momentum and charge differential cross section are extrapolated to other projectile/target systems; that is used in a transport calculation of Ne ions in a target of biological interest (water), with a collimator. We show that nuclear fragmentation produces a dispersion in the spatial and energy distributions, and that one light fragments have a range greater than the projectile range. That last point causes a distortion of the Bragg curve, and that distortion must be taken into account for the application of heavy ions to radiotherapy problems. 95 figs., 8 tabs
Relativistic scattering theory of two charged spinless particles
International Nuclear Information System (INIS)
Alt, E.O.; Hannemann
1985-01-01
In the framework of a relativistic quantum mechanics, the authors calculate for two spinless particles with Coulomb interaction exactly the partial-wave S-matrix and the full scattering amplitude. From the former they can extract the exact binding energies which, when expanded in powers of α, reproduce in the hydrogenic case the fourth-order result of a previous study. In the weak field limit, the latter coincides with the amplitude derived by another study from QED in eikonal approximation
Relativistic structure, stability, and gravitational collapse of charged neutron stars
International Nuclear Information System (INIS)
Ghezzi, Cristian R.
2005-01-01
Charged stars have the potential of becoming charged black holes or even naked singularities. We present a set of numerical solutions of the Tolman-Oppenheimer-Volkov equations that represents spherical charged compact stars in hydrostatic equilibrium. The stellar models obtained are evolved forward in time integrating the Einstein-Maxwell field equations. We assume an equation of state of a neutron gas at zero temperature. The charge distribution is taken as being proportional to the rest mass density distribution. The set of solutions present an unstable branch, even with charge-to-mass ratios arbitrarily close to the extremum case. We perform a direct check of the stability of the solutions under strong perturbations and for different values of the charge-to-mass ratio. The stars that are in the stable branch oscillate and do not collapse, while models in the unstable branch collapse directly to form black holes. Stars with a charge greater than or equal to the extreme value explode. When a charged star is suddenly discharged, it does not necessarily collapse to form a black hole. A nonlinear effect that gives rise to the formation of a shell of matter (in supermassive stars), is negligible in the present simulations. The results are in agreement with the third law of black hole thermodynamics and with the cosmic censorship conjecture
A search for relativistic particles with fractional electric charge at the Cern collider
DEFF Research Database (Denmark)
Banner, M.; Kofoed-Hansen, O.
1983-01-01
A search for relativistic particles with fractional electric charge has been performed at the CERN collider using a telescope of scintillation counters to detect particles with abnormally low ionisation. The thickness of the detector (40 gr cm−2) limits this search to particles without strong...
Cooling and focusing of a relativistic charged particle beam in crossed laser field
International Nuclear Information System (INIS)
Li Fuli
1987-01-01
A new method to focus a relativistic charged particle beam is suggested and studied. This idea is based on the use of the ponderomotive force which arises when a periodic electromagnetic field is created, as in the case of two crossed laser beams. (author)
Fragmentation of organic ions bearing fixed multiple charges observed in MALDI MS.
Lou, Xianwen; Li, Bao; de Waal, Bas F M; Schill, Jurgen; Baker, Matthew B; Bovee, Ralf A A; van Dongen, Joost L J; Milroy, Lech-Gustav; Meijer, E W
2018-01-01
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS) was used to analyze a series of synthetic organic ions bearing fixed multiple charges. Despite the multiple intrinsic charges, only singly charged ions were recorded in each case. In addition to the pseudo-molecular ions formed by counterion adduction, deprotonation and electron capture, a number of fragment ions were also observed. Charge splitting by fragmentation was found to be a viable route for charge reduction leading to the formation of the observed singly charged fragment ions. Unlike multivalent metal ions, organic ions can rearrange and/or fragment during charge reduction. This fragmentation process will evidently complicate the interpretation of the MALDI MS spectrum. Because MALDI MS is usually considered as a soft ionization technique, the fragment ion peaks can easily be erroneously interpreted as impurities. Therefore, the awareness and understanding of the underlying MALDI-induced fragmentation pathways is essential for a proper interpretation of the corresponding mass spectra. Due to the fragment ions generated during charge reduction, special care should be taken in the MALDI MS analysis of multiply charged ions. In this work, the possible mechanisms by which the organic ions bearing fixed multiple charges fragment are investigated. With an improved understanding of the fragmentation mechanisms, MALDI TOF MS should still be a useful technique for the characterization of organic ions with fixed multiple charges. Copyright © 2017 John Wiley & Sons, Ltd.
International Nuclear Information System (INIS)
Bondarenko, R.A.; Gulamov, K.G.; Gulyamov, U.G.; Chernov, G.M.
1983-01-01
We present the basic characteristics (multiplicities, distributions in transverse momenta, and correlations in the transverse plane) of fragments of the incident nucleus in inelastic interactions of relativistic 12 C nuclei in nuclear emulsion. We observe effects of the transverse motion of the fragmenting nucleus and its angular momentum. A qualitative and critical analysis of a number of commonly used theoretical approaches to the fragmentation of relativistic nuclei is given
2002-01-01
% EMU11 \\\\ \\\\ We propose to use nuclear emulsions for the study of nuclear collisions of $^{207}$Pb, $^{197}$Au, and any other heavy-ion beams when they are available. We have, in the past, used $^{32}$S at 200A~GeV and $^{16}$O at 200A and 60A~GeV from CERN (Experiment EMU08) and at present the analysis is going on with $^{28}$Si beam from BNL at 14.5A~GeV. It will be important to compare the previous and the present investigations with the new $^{207}$Pb beam at 60-160A~GeV. We want to measure in nuclear emulsion, on an event by event basis, shower particle multiplicity, pseudorapidity density and density fluctuations of charged particles, charge multiplicity and angular distributions of projectile fragments, production and interaction cross-sections of heavily ionizing particles emitted from the target fragmentation. Special emphasis will be placed on the analysis of events produced in the central collisions which are selected on the basis of low energy fragments emitted from the target excitation. It woul...
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.
CHARGED PARTICLE MULTIPLICITIES IN ULTRA-RELATIVISTIC AU+AU AND CU+CU COLLISIONS
Back, B. B.; Alver, B.; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Busza, W.; Carroll, A.; Chai, Z.; Chetluru, V.; Decowski, M. P.; Garcia, E.; Gburek, T.; George, N.; Gulbrandsen, K.; Halliwell, C.; Hamblen, J.; Harnarine, I.; Hauer, M.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Holynski, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Khan, N.; Kulinich, P.; Kuo, C. M.; Li, W.; Lin, W. T.; Loizides, C.; Manly, S.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Reed, C.; Richardson, E.; Roland, C.; Roland, G.; Sagerer, J.; Seals, H.; Sedykh, I.; Smith, C. E.; Stankiewicz, M. A.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Szostak, A.; Tonjes, M. B.; Trzupek, A.; Vale, C.; Vannieuwenhuizen, G. J.; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Walters, P.; Wenger, E.; Willhelm, D.; Wolfs, F. L. H.; Wosiek, B.; Wozniak, K.; Wyngaardt, S.; Wyslouch, B.
The PHOBOS collaboration has carried out a systematic study of charged particle multiplicities in Cu+Cu and Au+Au collisions at the Relativistic Heavy-Ion Collider (RHIC) at Brookhaven National Laboratory. A unique feature of the PHOBOS detector is its ability to measure charged particles over a very wide angular range from 0.5° to 179.5° corresponding to |η| <5.4. The general features of the charged particle multiplicity distributions as a function of pseudo-rapidity, collision energy and centrality, as well as system size, are discussed.
Zhang, Ruili; Wang, Yulei; He, Yang; Xiao, Jianyuan; Liu, Jian; Qin, Hong; Tang, Yifa
2018-02-01
Relativistic dynamics of a charged particle in time-dependent electromagnetic fields has theoretical significance and a wide range of applications. The numerical simulation of relativistic dynamics is often multi-scale and requires accurate long-term numerical simulations. Therefore, explicit symplectic algorithms are much more preferable than non-symplectic methods and implicit symplectic algorithms. In this paper, we employ the proper time and express the Hamiltonian as the sum of exactly solvable terms and product-separable terms in space-time coordinates. Then, we give the explicit symplectic algorithms based on the generating functions of orders 2 and 3 for relativistic dynamics of a charged particle. The methodology is not new, which has been applied to non-relativistic dynamics of charged particles, but the algorithm for relativistic dynamics has much significance in practical simulations, such as the secular simulation of runaway electrons in tokamaks.
Momentum and charge transport in non-relativistic holographic fluids from Hořava gravity
Energy Technology Data Exchange (ETDEWEB)
Davison, Richard A. [Department of Physics, Harvard University, Cambridge, MA 02138 (United States); Grozdanov, Sašo [Instituut-Lorentz for Theoretical Physics, Leiden University, Niels Bohrweg 2, Leiden 2333 CA (Netherlands); Janiszewski, Stefan [Department of Physics and Astronomy, University of Victoria, Victoria, BC, V8W 3P6 (Canada); Kaminski, Matthias [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487 (United States)
2016-11-28
We study the linearized transport of transverse momentum and charge in a conjectured field theory dual to a black brane solution of Hořava gravity with Lifshitz exponent z=1. As expected from general hydrodynamic reasoning, we find that both of these quantities are diffusive over distance and time scales larger than the inverse temperature. We compute the diffusion constants and conductivities of transverse momentum and charge, as well the ratio of shear viscosity to entropy density, and find that they differ from their relativistic counterparts. To derive these results, we propose how the holographic dictionary should be modified to deal with the multiple horizons and differing propagation speeds of bulk excitations in Hořava gravity. When possible, as a check on our methods and results, we use the covariant Einstein-Aether formulation of Hořava gravity, along with field redefinitions, to re-derive our results from a relativistic bulk theory.
International Nuclear Information System (INIS)
Agakishiev, G.; Man'yakov, P.K.; Drees, A.
1997-01-01
The simple and fast detector of charged particle multiplicity for relativistic nucleus-nucleus collision studies is performed. The multiplicity detector has been designed for the first level trigger of the CERES/NA45 experiment to study Pb-Au collisions at CERN SPS energies. The detector has allowed a realization of the 40 ns trigger for selection of events with definite impact parameter. The construction, operation characteristics, method of calibration, and testing results are described in detail
Self-modulated dynamics of a relativistic charged particle beam in plasma wake field excitation
Energy Technology Data Exchange (ETDEWEB)
Akhter, T.; Fedele, R. [Dipartimento di Fisica ‘Ettore Pancini’, Università di Napoli Federico II and INFN Sezione di Napoli, Napoli (Italy); Nicola, S. De [CNR-SPIN and INFN Sezione di Napoli, Napoli (Italy); Tanjia, F. [Dipartimento di Fisica ‘Ettore Pancini’, Università di Napoli Federico II and INFN Sezione di Napoli, Napoli (Italy); Jovanović, D. [Institute of Physics, University of Belgrade, Belgrade (Serbia); Mannan, A. [Department of Physics, Jahangirnagar University, Savar, Dhaka (Bangladesh)
2016-09-01
The self-modulated dynamics of a relativistic charged particle beam is provided within the context of the theory of plasma wake field excitation. The self-consistent description of the beam dynamics is provided by coupling the Vlasov equation with a Poisson-type equation relating the plasma wake potential to the beam density. An analysis of the beam envelope self-modulation is then carried out and the criteria for the occurrence of the instability are discussed thereby.
International Nuclear Information System (INIS)
Webb, M.L.
1987-06-01
Relativistic heavy ion collisions may be classified as central (and near central), peripheral, and grazing with each collision type producing different proton and other charged projectile fragment scattering mechanisms and characteristics. This report focuses on peripheral and grazing collisions in the fragmentation of Carbon-12 into Boron-11 and a proton, testing models of the kinetics involved in this reaction. The data were measured at the Heavy Ion Superconducting Spectrometer (HISS) at Lawrence Berkeley Laboratory and include excitation energy for the p/Boron-11 pair, and rapidity versus transverse momentum for protons and Boron-11. 58 refs., 35 figs., 8 tabs
International Nuclear Information System (INIS)
Erokhin, N.S.; Zol'nikova, N.N.; Kuznetsov, E.A.; Mikhajlovskaya, L.A.
2010-01-01
Based on numerical calculations considered the relativistic acceleration of charged particles in space plasma when surfing on the spatially localized package of electromagnetic waves. The problem is reduced to the study of unsteady, nonlinear equation for the wave phase at the carrier frequency at the location of the accelerated charge, which is solved numerically. We study the temporal dynamics of the relativistic factor, the component of momentum and velocity of the particle, its trajectory is given gyro-rotation in an external magnetic field after the departure of the effective potential well. Dependence of the dynamics of a particle interacting with the wave of the sign of the velocity of the charge along the wave front. We formulate the optimal conditions of the relativistic particle acceleration wave packet, indicate the possibility of again (after a number gyro-turnover) charge trapping wave with an additional relativistic acceleration.
Production of highly charged ions of argon by optical field ionization in a relativistic laser field
International Nuclear Information System (INIS)
Sagisaka, Akito; Akahane, Yutaka; Aoyama, Makoto; Nakano, Fumihiko; Yamakawa, Koichi
2001-01-01
We observed the highly charged ions of argon by optical field ionization in a relativistic intensity regime. Charge states up to Ar 15+ were produced at the highest intensity of 800 nm, linearly polarized 20 fs Ti: sapphire laser pulses. The peak intensity of the pulse is determined by comparing the measured ion production curve for Ar 9+ with ADK theory. The results of these measurements of the ionization indicate that the maximum peak intensity is achieved to ∼2x10 19 W/cm 2 . (author)
Energy Technology Data Exchange (ETDEWEB)
Drescher, H.J
1999-06-11
In this work we have developed hard processes and string fragmentation in the framework of interactions at relativistic energies. The hypothesis of the universality of high energy interactions means that many elements of heavy ion collisions can be studied and simulated in simpler nuclear reactions. In particular this hypothesis implies that the fragmentation observed in the reaction e{sup +}e{sup -} follows the same rules as in the collision of 2 lead ions. This work deals with 2 nuclear processes: the e{sup +}e{sup -} annihilation reaction and the deep inelastic diffusion. For the first process the string model has been developed to simulate fragmentation by adding an artificial breaking of string due to relativistic effects. A monte-Carlo method has been used to determine the points in a Minkowski space where this breaking occurs. For the second reaction, the theory of semi-hard pomerons is introduced in order to define elementary hadron-hadron interactions. The model of fragmentation proposed in this work can be applied to more complicated reactions such as proton-proton or ion-ion collisions.
Production study of light fragments emitted at low angle in relativistic heavy ion collisions
International Nuclear Information System (INIS)
Bastid, N.
1987-03-01
The Diogene plastic wall was built in order to study fragment production in a 0 O -6 O angular range. After generalities on heavy ion collisions and a description of the Diogene detector, methods used for data analysis allowing identification of charged particles and measurement of their energy and emission angle are presented. From correlation studies between the Diogene events and the plastic wall events, we can have an information on the centrality of collisions. On the other hand, the study of differential cross sections shows two existing sources: one formed by the projectile remnant, at a velocity close to beam velocity and a source of intermediary rapidity formed by the participants. We have shown that even for very central collisions and heavy targets, the target nucleus remains partially transparent. In order to explain projectile fragmentation mechanism, we have used two models: a coalescence model and a thermal model. The first model gives the value of the coalescence radius. It seems that this model does not apply to angles nearing 0 O . With the thermal model, we have been able to sort out apparent temperature values which confirm the weak excitation energy of the projectile remnant [fr
Ionization and bound-state relativistic quantum dynamics in laser-driven multiply charged ions
International Nuclear Information System (INIS)
Hetzheim, Henrik
2009-01-01
The interaction of ultra-strong laser fields with multiply charged hydrogen-like ions can be distinguished in an ionization and a bound dynamics regime. Both are investigated by means of numerically solving the Dirac equation in two dimensions and by a classical relativistic Monte-Carlo simulation. For a better understanding of highly nonlinear physical processes the development of a well characterized ultra-intense relativistic laser field strength has been driven forward, capable of studying e.g. the magnetic field effects of the laser resulting in an additional electron motion in the laser propagation direction. A novel method to sensitively measure these ultra-strong laser intensities is developed and employed from the optical via the UV towards the XUV frequency regime. In the bound dynamics field, the determination of multiphoton transition matrixelements has been investigated between different bound states via Rabi oscillations. (orig.)
Ionization and bound-state relativistic quantum dynamics in laser-driven multiply charged ions
Energy Technology Data Exchange (ETDEWEB)
Hetzheim, Henrik
2009-01-14
The interaction of ultra-strong laser fields with multiply charged hydrogen-like ions can be distinguished in an ionization and a bound dynamics regime. Both are investigated by means of numerically solving the Dirac equation in two dimensions and by a classical relativistic Monte-Carlo simulation. For a better understanding of highly nonlinear physical processes the development of a well characterized ultra-intense relativistic laser field strength has been driven forward, capable of studying e.g. the magnetic field effects of the laser resulting in an additional electron motion in the laser propagation direction. A novel method to sensitively measure these ultra-strong laser intensities is developed and employed from the optical via the UV towards the XUV frequency regime. In the bound dynamics field, the determination of multiphoton transition matrixelements has been investigated between different bound states via Rabi oscillations. (orig.)
International Nuclear Information System (INIS)
Karabut, P.V.; Chugreev, Yu.V.
1989-01-01
The relativistic theory of gravitation (RTG), which is constructed on the basis of Minkowski spacetime, the geometrization principle, and the notion of the gravitational field var-phi mn as a physical field in the spirit of Faraday and Maxwell, explains all known gravitational experiments and gives a new prediction for the evolution of the universe, collapse, etc. The RTG determines the structure of the gravitational field as a field possessing spins 2 and 0 and all conservation laws for energy, momentum, and angular momentum. An exact solution of the complete simultaneous system of equations of the relativistic theory of gravitation and Maxwell's equations is found in the axisymmetric case for an electrically charged rotating body. The uniqueness of this solution is proved
Formation and fragmentation of quadruply charged molecular ions by intense femtosecond laser pulses.
Yatsuhashi, Tomoyuki; Nakashima, Nobuaki
2010-07-22
We investigated the formation and fragmentation of multiply charged molecular ions of several aromatic molecules by intense nonresonant femtosecond laser pulses of 1.4 mum with a 130 fs pulse duration (up to 2 x 10(14) W cm(-2)). Quadruply charged states were produced for 2,3-benzofluorene and triphenylene molecular ion in large abundance, whereas naphthalene and 1,1'-binaphthyl resulted only in up to triply charged molecular ions. The laser wavelength was nonresonant with regard to the electronic transitions of the neutral molecules, and the degree of fragmentation was strongly correlated with the absorption of the singly charged cation radical. Little fragmentation was observed for naphthalene (off-resonant with cation), whereas heavy fragmentation was observed in the case of 1,1'-binaphthyl (resonant with cation). The degree of H(2) (2H) and 2H(2) (4H) elimination from molecular ions increased as the charge states increased in all the molecules examined. A striking difference was found between triply and quadruply charged 2,3-benzofluorene: significant suppression of molecular ions with loss of odd number of hydrogen was observed in the quadruply charged ions. The Coulomb explosion of protons in the quadruply charged state and succeeding fragmentation resulted in the formation of triply charged molecular ions with an odd number of hydrogens. The hydrogen elimination mechanism in the highly charged state is discussed.
Supergroup extensions: from central charges to quantization through relativistic wave equations
International Nuclear Information System (INIS)
Aldaya, V.; Azcarraga, J.A. de.
1982-07-01
We give in this paper the finite group law of a family of supergroups including the U(1)-extended N=2 super-Poincare group. From this family of supergroups, and by means of a canonical procedure, we are able to derive the Klein-Gordon and Dirac equations for the fields contained in the superfield. In the process, the physical content of the central charge as the mass parameter and the role of covariant derivatives are shown to come out canonically from the group structure, and the U(1)-extended supersymmetry is seen as necessary for the geometric quantization of the relativistic elementary systems. (author)
Isegawa, Miho; Gao, Jiali; Truhlar, Donald G
2011-08-28
Molecular fragmentation algorithms provide a powerful approach to extending electronic structure methods to very large systems. Here we present a method for including charge transfer between molecular fragments in the explicit polarization (X-Pol) fragment method for calculating potential energy surfaces. In the conventional X-Pol method, the total charge of each fragment is preserved, and charge transfer between fragments is not allowed. The description of charge transfer is made possible by treating each fragment as an open system with respect to the number of electrons. To achieve this, we applied Mermin's finite temperature method to the X-Pol wave function. In the application of this method to X-Pol, the fragments are open systems that partially equilibrate their number of electrons through a quasithermodynamics electron reservoir. The number of electrons in a given fragment can take a fractional value, and the electrons of each fragment obey the Fermi-Dirac distribution. The equilibrium state for the electrons is determined by electronegativity equalization with conservation of the total number of electrons. The amount of charge transfer is controlled by re-interpreting the temperature parameter in the Fermi-Dirac distribution function as a coupling strength parameter. We determined this coupling parameter so as to reproduce the charge transfer energy obtained by block localized energy decomposition analysis. We apply the new method to ten systems, and we show that it can yield reasonable approximations to potential energy profiles, to charge transfer stabilization energies, and to the direction and amount of charge transferred. © 2011 American Institute of Physics
Charge distributions and correlations in fragmentation models for soft hadron collisions
International Nuclear Information System (INIS)
Wolf, E.A. de
1984-01-01
Data on charge distributions and charge correlations in pp and meson-proton interactions at PS and SPS energies are successfully compared with the Lund fragmentation model for low-psub(T) hadron collisions. It is argued that local conservation of quantum numbers and resonance production, as implemented in fragmentation models, are sufficient ingredients to explain most of the available experimental results at these energies. No necessity is found for dual-sheet contributions considered in DTU-based parton models. (orig.)
Lin, M. C.; Verboncoeur, J.
2016-10-01
A maximum electron current transmitted through a planar diode gap is limited by space charge of electrons dwelling across the gap region, the so called space charge limited (SCL) emission. By introducing a counter-streaming ion flow to neutralize the electron charge density, the SCL emission can be dramatically raised, so electron current transmission gets enhanced. In this work, we have developed a relativistic self-consistent model for studying the enhancement of maximum transmission by a counter-streaming ion current. The maximum enhancement is found when the ion effect is saturated, as shown analytically. The solutions in non-relativistic, intermediate, and ultra-relativistic regimes are obtained and verified with 1-D particle-in-cell simulations. This self-consistent model is general and can also serve as a comparison for verification of simulation codes, as well as extension to higher dimensions.
International Nuclear Information System (INIS)
Ibnouzahir, M.
1995-03-01
The study of relativistic heavy ion collisions permit an approach of the properties of dense and not hadronic matter, and an analysis of the reaction mechanisms. Such studies are also interesting on the biological point of view, since there exist now well defined projects concerning the radiotherapy with high LET particles as neutrons, protons, heavy ions. It is thus necessary to have a good understanding of the processes which occur in the propagation of a relativistic heavy ion beam (E≥ 100 A.MeV) in matter. We have elaborated a three dimensional transport code, using a Monte Carlo method, in order to describe the propagation of Ne and Ar ions in water. Violent nuclear collisions giving fragmentation process have been taken into account by use of the FREESCO program. We have tested the validity of our transport model and we show an important change of the energy deposition at the vicinity of the Bragg peak; such a distortion, due mainly to fragmentation reactions, is of a great interest for biological applications. (author)
Hydrodynamics with chiral anomaly and charge separation in relativistic heavy ion collisions
Energy Technology Data Exchange (ETDEWEB)
Yin, Yi, E-mail: yyin@bnl.gov [Physics Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Liao, Jinfeng, E-mail: liaoji@indiana.edu [Physics Department and Center for Exploration of Energy and Matter, Indiana University, 2401 N Milo B. Sampson Lane, Bloomington, IN 47408 (United States); RIKEN BNL Research Center, Bldg. 510A, Brookhaven National Laboratory, Upton, NY 11973 (United States)
2016-05-10
Matter with chiral fermions is microscopically described by theory with quantum anomaly and macroscopically described (at low energy) by anomalous hydrodynamics. For such systems in the presence of external magnetic field and chirality imbalance, a charge current is generated along the magnetic field direction — a phenomenon known as the Chiral Magnetic Effect (CME). The quark–gluon plasma created in relativistic heavy ion collisions provides an (approximate) example, for which the CME predicts a charge separation perpendicular to the collisional reaction plane. Charge correlation measurements designed for the search of such signal have been done at RHIC and the LHC for which the interpretations, however, remain unclear due to contamination by background effects that are collective flow driven, theoretically poorly constrained, and experimentally hard to separate. Using anomalous (and viscous) hydrodynamic simulations, we make a first attempt at quantifying contributions to observed charge correlations from both CME and background effects in one and same framework. The implications for the search of CME are discussed.
Collisions of Oq+ with neutral C-60 : Charge transfer and fragmentation
Schlatholter, T; Hoekstra, R; Morgenstern, R
1998-01-01
Fragmentation of C-60 fullerenes by collisions with multiply charged Oq+ ions (1 less than or equal to q less than or equal to 7) has been studied experimentally for Oq+ collision energies of 1.16 keV amu(-1) For high projectile charges the potential energy of the projectiles is mainly responsible
Phenomenological formula for the inclusive fragmentation cross sections of relativistic heavy ions
International Nuclear Information System (INIS)
Masuda, N.; Inoue, K.; Ito, Y.
1981-01-01
We study phenomenologically the inclusive fragmentation cross section data of 12 C and 16 O at 2.1 GeV/nucleon, and 56 Fe at 1.88 GeV/nucleon upon collisions with a 12 C target. The main assumptions on the fragmentation mechanism are the diffractive excitation of the high energy beam nucleus into the state of virtual dissociation and its direct decay into two fragments as was previously proposed by the authors. Starting from Izosimova et al.'s formula for the same problem, we derive a phenomenological inclusive cross section formula for fragment production, which is applicable to both ordinary and very light fragments. We find that the data can be understood if we assume that the fragments are being produced not only in their ground states but also in the low lying excited states. Our formula relates the inclusive cross section of light fragment (cluster) to the effective number of the same cluster in the low lying excited states of the beam nucleus
Bifurcation Mode of Relativistic and Charge-Displacement Self-Channeling
International Nuclear Information System (INIS)
BORISOV, A.B.; CAMERON, STEWART M.; LUK, TING S.; NELSON, THOMAS R.; VAN TASSLE, A.J.; SANTORO, J.; SCHROEDER, W.A.; DAI, Y.; LONGWORTH, J.W.; BOYER, K.; RHODES, C.K.
2000-01-01
Stable self-channeling of ultra-powerful (P 0 - 1 TW -1 PW) laser pulses in dense plasmas is a key process for many applications requiring the controlled compression of power at high levels. Theoretical computations predict that the transition zone between the stable and highly unstable regimes of relativistic/charge-displacement self-channeling is well characterized by a form of weakly unstable behavior that involves bifurcation of the propagating energy into two powerful channels. Recent observations of channel instability with femtosecond 248 nm pulses reveal a mode of bifurcation that corresponds well to these theoretical predictions. It is further experimentally shown that the use of a suitable longitudinal gradient in the plasma density can eliminate this unstable behavior and restore the efficient formation of stable channels
Spin dynamics in relativistic ionization with highly charged ions in super-strong laser fields
International Nuclear Information System (INIS)
Klaiber, Michael; Yakaboylu, Enderalp; Bauke, Heiko; Hatsagortsyan, Karen Z; Müller, Carsten; Paulus, Gerhard G
2014-01-01
Spin dynamics and induced spin effects in above-threshold ionization of hydrogenlike highly charged ions in super-strong laser fields are investigated. Spin-resolved ionization rates in the tunnelling regime are calculated by employing two versions of a relativistic Coulomb-corrected strong-field approximation (SFA). An intuitive simpleman model is developed which explains the derived scaling laws for spin flip and spin asymmetry effects. The intuitive model as well as our ab initio numerical simulations support the analytical results for the spin effects obtained in the dressed SFA where the impact of the laser field on the electron spin evolution in the bound state is taken into account. In contrast, the standard SFA is shown to fail in reproducing spin effects in ionization even at a qualitative level. The anticipated spin-effects are expected to be measurable with modern laser techniques combined with an ion storage facility. (paper)
A fully relativistic approach for calculating atomic data for highly charged ions
Energy Technology Data Exchange (ETDEWEB)
Zhang, Hong Lin [Los Alamos National Laboratory; Fontes, Christopher J [Los Alamos National Laboratory; Sampson, Douglas H [PENNSYLVANIA STATE UNIV
2009-01-01
We present a review of our fully relativistic approach to calculating atomic data for highly charged ions, highlighting a research effort that spans twenty years. Detailed discussions of both theoretical and numerical techniques are provided. Our basic approach is expected to provide accurate results for ions that range from approximately half ionized to fully stripped. Options for improving the accuracy and range of validity of this approach are also discussed. In developing numerical methods for calculating data within this framework, considerable emphasis is placed on techniques that are robust and efficient. A variety of fundamental processes are considered including: photoexcitation, electron-impact excitation, electron-impact ionization, autoionization, electron capture, photoionization and photorecombination. Resonance contributions to a variety of these processes are also considered, including discussions of autoionization, electron capture and dielectronic recombination. Ample numerical examples are provided in order to illustrate the approach and to demonstrate its usefulness in providing data for large-scale plasma modeling.
International Nuclear Information System (INIS)
Bateman, J.E.
1978-12-01
A method is described of obtaining a useful degree of improvement in the particle discrimination capability of multiwire proportional counters. The normal multiple sampling technique using a suitable bias to combat the small magnitude of the relativistic rise in the ionization energy loss and the wide pulse height distributions obtained in thin gas counters requires a large number of samples for useful discrimination. In the method reported, this number is reduced by suppressing the delta ray contribution to the total charge pulse from the anode wire. A monte carlo model convoluting the 'delta ray suppressed' data from a one sample detector shows that when it is required to separate pions and electrons at 1 GeV/C with a detection efficiency for the electron of 90%, a 'suppressor' circuit can achieve a pion rejection ratio of 250:1 with 82 samples, whereas the truncated mean approach (lowest 70% of samples) requires 100 samples. (UK)
Asymptotic theory of charge exchange for relativistic velocities and binding energies
International Nuclear Information System (INIS)
Demkov, Yu.N.; Ostrovskij, V.N.; Shevchenko, S.I.
1983-01-01
The asymptotic theory of charge exchange (ATCE) at a large shock parameter rho is applied to the case of relativistic velocities and binding energies. The charge exchange reaction (1+e)+2 → 1+(e+2), when an electron from the bound 1Ssub(1/2) state on one particle transforms to the 1Ssub(1/2) state on the other, is considered. Oasic features of the method are as follows: 1) the representation of the transition amplitude in the form of multidimensional integral over some hypersurface; 2) the use of the saddle-point method for calculating necessary multidimensional integrals; 3) the refinement of wave functions as compared with the case of the absence of the interaction. The ATCE (at rho → infinity) makes it possible to obtain analytical results whose accuracy is determined solely with the shock parameter rho. A basic term of charge exchange amplitude asymptotics for 1Ssub(1/2) → 1Ssub(1/2) transitions has been calculated. It is possible to consider the ATCE as a peculiar reference with which theoretical and experimental results can be compared as well as to use the ATCE as boundary conditions during numerical calculations
Maksyuta, N. V.; Vysotskii, V. I.; Efimenko, S. V.
2016-07-01
The paper deals with the investigation of the orientation motion of relativistic electrons in charged (111) planes and charged [110] axes of lithium halides ionic crystals of LiF, LiCl, LiBr and LiI. On the basis of these investigations the spectra of quasicharacteristic radiation for the electron beams with various Lorentz-factors both in planar and axial cases have been calculated numerically.
International Nuclear Information System (INIS)
Napolitani, P.; Tassan-Got, L.; Bernas, M.; Armbruster, P.
2003-04-01
Secondary reactions induced by relativistic beams in inverse kinematics in a thick target are relevant in several fields of experimental physics and technology, like secondary radioactive beams, production of exotic nuclei close to the proton drip line, and cross-section measurements for applications of spallation reactions for energy production and incineration of nuclear wastes. A general mathematical formulation is presented and successively applied as a tool to disentangle the primary reaction yields from the secondary production in the measurement of fission of a 238 U projectile impinging on a proton target at the energy of 1 A GeV. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Milant' ev, V. P., E-mail: vmilantiev@sci.pfu.edu.ru; Castillo, A. J., E-mail: vmilant@mail.ru [Peoples' Friendship University of Russia (Russian Federation)
2013-04-15
Averaged relativistic equations of motion of a charged particle in the field of intense electromagnetic radiation have been obtained in the geometrical optics approximation using the Bogoliubov method. Constraints are determined under which these equations are valid. Oscillating additions to the smoothed dynamical variables of the particle have been found; they are reduced to known expressions in the case of the circularly and linearly polarized plane waves. It has been shown that the expressions for the averaged relativistic force in both cases contain new additional small terms weakening its action. The known difference between the expressions for the ponderomotive force in the cases of circularly and linearly polarized waves has been confirmed.
Evidence for anomalous nuclei among relativistic projectile fragments at Bevalac energies
International Nuclear Information System (INIS)
Heckman, H.H.
1981-01-01
Two independent emulsion experiments using beams of 16 O and 56 Fe at approximately 2 GeV/nucleon find that the reaction mean free paths of projectile fragments (PF) with Z between 3 and 26 are shorter for a few centimeters after their emission than at larger distances, or than predicted from experiments on beam nuclei. Under the assumption that there are two populations of PF, a best fit to the data is obtained when approximately 6% of the PF have an anomalously short mean free path. The anomalous property of PF persists in subsequent fragmentation reactions. 6 figures
A new approach to the semi-classical relativistic two-body problem for charged fermions
International Nuclear Information System (INIS)
Leiter, D.
1978-01-01
Generalizing from a recently developed hybrid formulation of classical electrodynamics with ''direct (charge-field) action'' structure an analogous semi-classical Dirac formulation of the theory is constructed, which is capable of describing the semi-classical quantum mechanics of two identical spin-1/2 particles. This semi-classical formulation is to be used as a heuristic aid in searching for the theoretical structure of a fully ''second quantized'' theory. The Pauli exclusion principle is incorporated by making the interaction fields (in the action principle) antisymmetric with respect to ''charge-field'' labeling. In this manner, ''position correlation'' effects associated with ''configuration interaction'' can also be accounted for. By studying the nature of the stationary-state solutions, the formalism is compared with the conventional quantum-mechanical one (to understand the similarities and the differences between this approach and the usual correlated Hartree-Fock approximation of ordinary relativistic quantum theory). The stationary-state solutions to the semi-classical formalism are shown to closely approximate the usual quantum-mechanical solutions when the wave functions are represented as a superposition of Slater determinants of Dirac-Coulombic-type wave functions with radial parts having a form which extremizes the total Breit energy. The manner in which this semi-classical theory might be extended to a fully ''second quantized'' formalism is sketched. (author)
Directory of Open Access Journals (Sweden)
Agostino Marinelli
2010-11-01
Full Text Available Longitudinal space-charge forces from density fluctuations generated by shot noise can be a major source of microbunching instability in relativistic high brightness electron beams. The gain in microbunching due to this effect is broadband, extending at least up to optical frequencies, where the induced structure on the beam distribution gives rise to effects such as coherent optical transition radiation. In the high-frequency regime, theoretical and computational analyses of microbunching formation require a full three-dimensional treatment. In this paper we address the problem of space-charge induced optical microbunching formation in the high-frequency limit when transverse thermal motion due to finite emittance is included for the first time. We derive an analytical description of this process based on the beam’s plasma dielectric function. We discuss the effect of transverse temperature on the angular distribution of microbunching gain and its connection to the physics of Landau damping in longitudinal plasma oscillations. Application of the theory to a relevant experimental scenario is discussed. The analytical results obtained are then compared to the predictions arising from high resolution three-dimensional molecular dynamics simulations.
International Nuclear Information System (INIS)
Engelage, J.; Crawford, H.J.; Greiner, L.; Kuo, C.
1996-06-01
The Heavy Ion Spectrometer System (HISS) at the LBL Bevalac provided a unique facility for measuring projectile fragmentation cross sections important in deconvolving the Galactic Cosmic Ray (GCR) source composition. The general characteristics of the apparatus specific to this application are described and the main features of the event reconstruction and analysis used in the TRANSPORT experiment are discussed
Kinematical properties of spectator fragments in heavy-ion collisions at relativistic energies
International Nuclear Information System (INIS)
Bacquias, A.
2008-07-01
Contrary to central collisions experiments, some experiments are designed for the investigation of nuclear-matter properties thanks to spectator matter. These experiments concentrate their selection on events of peripheral and mid-peripheral collisions. Spectator matter is not subject to compression but is highly excited. The observables related to spectator fragments can then be used as probes on nuclear matter at low density in the case of mid-peripheral collisions. Recently, experiments with the Fragment Separator (FRS) at GSI have proven to be suited for yielding valuable complementary information to spectator matter studies. We will first give an overview of the types of reaction relevant for this study and the different features that condition the reaction mechanisms leading to fragmentation. In the second chapter, we will describe the experimental set-up used at the FRS and explain the role of each detector and the method to exploit these data at best. In the third chapter we will concentrate our efforts on kinematics data from a 136 Xe + Pb experiment at the energy of 1 GeV per nucleon. Experimental results come in the fourth chapter and they are interpreted and discussed in chapters 5, 6 and 7. We will first comment the shapes of the velocity spectra and discuss the link between observation and physical processes. The surprising fact that one has means to assess the centrality despite the low acceptance of the experimental set-up will be underlined. This new way of presenting the data will permit a new approach to the nucleon-nucleon cross-section, by making comparison with theoretical models possible. Eventually, we will concentrate on the width of the velocity spectra. After going through previous models and predictions we will present a new description of the reaction mechanisms and their influence on the kinematics of observed fragments, reliable for a very broad range of fragments. (A.C.)
International Nuclear Information System (INIS)
Stoehlker, T.; Mokler, P.H.; Kozhuharov, C.; Warczak, A.
1996-10-01
The photoelectric effect in the near relativistic energy regime of 80 to 350 keV is studied by the time-reversed process in ion-atom collisions, i.e. by the radiative capture of a quasi-free target electron. We review shell and subshell differential photon-angular distribution studies of radiative capture into highly-charged uranium ions. The experimental data are compared with exact relativistic calculations and give detailed insight into both the atomic structure of high-Z few-electron ions and into the fundamental electron-photon interaction process involved. In particular it is shown that the angular-differential measurements provide a unique method to study the magnetic interaction in relativistic electron-photon encoun- (orig.)
Separation and implantation of relativistic 86Kr-fragments at the FRS
International Nuclear Information System (INIS)
Czajkowski, S.; Bernas, M.; Dessagne, Ph.; Miehe, Ch.; Audi, G.; Lee, J.K.P.
1993-01-01
Neutron-rich Co and Fe isotopes produced by 86 Kr projectile fragmentation at 500 MeV/u have been separated and identified using the Fragment Separator (FRS) in a bunched energy mode. 66 Co and 65 Fe ions were selectively implanted in a double PIN-diode array where the β-decay signals were measured. The half-lives were deduced from time correlations between implantation and β-decay signals. The re-measurement of the 66 Co half-life confirms the isotope identification. The value of 65 Fe half-life was found to be 0.45±0.15 s. (authors). 18 refs., 5 figs
Rybar, Martin; The ATLAS collaboration
2018-01-01
Highly energetic jets produced in ultra-relativistic nuclear collisions are considered to be direct probes to study the properties of the hot and dense QCD matter created in these collisions. The measurement of the fragmentation functions of jets into charged particles in Pb+Pb collisions is sensitive to the strength and mechanism of jet quenching. In this talk, we present the latest measurement of the internal structure of jets and the angular distributions of charged particles within and around jets performed with the ATLAS detector. Fragmentation functions in Pb+Pb collisions and distributions of the transverse momentum of charged particles are compared to the same quantities measured in pp collisions at the same collision energy. Measurements are presented as a function of collision centrality, jet transverse momentum, and jet rapidity at 2.76 and 5.02 TeV. Furthermore, a new measurement of the angular distributions of charged-particles with respect to jet axis extended to distances outside the jet radius...
International Nuclear Information System (INIS)
Toms, D.J.
1994-01-01
It is shown how the effective action formalism and ζ-function regularization can be used to study Bose-Einstein condensation for a relativistic charged scalar field in a general homogeneous magnetic field in a spacetime of arbitrary dimension. In the special case where the magnetic field has only one component, Bose-Einstein condensation occurs at high temperature only for D≥5 where D is the spatial dimension. When Bose-Einstein condensation does occur the ground-state expectation value of the scalar field is not constant and we determine its value. If the magnetic field has p independent nonzero components we show that the condition for Bose-Einstein condensation is D≥3+2p. In particular, Bose-Einstein condensation can never occur if the magnetic field has all of its independent components nonzero. The problem of Bose-Einstein condensation in a cylindrical box in D spatial dimensions with a uniform magnetic field directed along the axis of the cylinder is also discussed
Tumakov, Dmitry A.; Telnov, Dmitry A.; Maltsev, Ilia A.; Plunien, Günter; Shabaev, Vladimir M.
2017-10-01
We develop an efficient numerical implementation of the relativistic time-dependent density functional theory (RTDDFT) to study multielectron highly-charged ions subject to intense linearly-polarized laser fields. The interaction with the electromagnetic field is described within the electric dipole approximation. The resulting time-dependent relativistic Kohn-Sham (RKS) equations possess an axial symmetry and are solved accurately and efficiently with the help of the time-dependent generalized pseudospectral method. As a case study, we calculate multiphoton ionization probabilities of the neutral argon atom and argon-like xenon ion. Relativistic effects are assessed by comparison of our present results with existing non-relativistic data.
A study on the effects of relativistic heavy charged particles on the cellular microenvironment
Costes, Sylvain Vincent
This study was done under the National Aeronautics Space Administration (NASA) effort to assess the effect of cosmic radiation on astronauts during a 3 year mission to Mars. Carcinogenesis is known to be induced more efficiently by cosmic radiation. Our attention was turned towards one of the most efficient cosmic particles in inducing cancer, relativistic Fe, and focused in assessing its effect on the cellular microenvironment (ECM). Previous observations on mammary glands were showing irregularities in the immunoreactivity of the ECM protein laminin one hour after whole body irradiation with 1GeV/amu Fe ions for a dose of 0.8 Gy. This effect was not observed after 5 Gy γ-rays exposure. The rapidity of such a change suggested that the effect might be due to a physical event specific to relativistic charged particles (HZE), rather than a biological event. Our study showed that this effect is actually a complex and rapid response of the microenvironment to highly ionizing radiation. It involves a fast disruption of the basement membrane of the ECM induced by the highly localized ionization and reactive oxygen formation around the track of the Fe ion. This disruption triggers further chemical and biological responses involved in the remodeling of the laminin network in the basement membrane. A metalloproteinase is suspected to be the intermediate protease affecting laminin. The HZE effect on the microenvironment was seen in both mouse mammary glands and skin, but the laminin isoforms sensitive to Fe ions were different for each organ, with a clear disruption of laminin-1 network in skin and of laminin-5 in mammary glands. In addition, the laminin receptor integrins seem to be involved in this mechanism, but its contribution is unclear at this point. Finally, such studies suggest a shift from the concept of relative biological effectiveness (RBE) used in classical radiation biology since the effect is only seen with HZE at viable whole body doses. In addition, this
International Nuclear Information System (INIS)
Yuan, Luke C.L.; Chen, C.P.; Huang, C.Y.; Lee, S.C.; Waysand, G.; Perrier, P.; Limagne, D.; Jeudy, V.; Girard, T.
2000-01-01
A novel transition radiation detector (TRD) utilizing superheated superconducting microspheres of tin of 22-26, 27-32 and 32-38 μm in diameter, respectively, has been constructed which is capable of measuring accurately the energy of relativistic high-energy charged particles. The test has been conducted in a high-energy electron beam facility at the CERN PS in the energy range of 1-10 GeV showing an energy dependence of the TR X-ray photon produced and hence the value γ=E/mc 2 of the charged particle
Fragmentation of C2H4 by charge-changing collisions of O2+ ions
International Nuclear Information System (INIS)
Sato, S.; Mizuno, T.; Yamada, T.; Imai, M.; Shibata, H.; Itoh, A.; Tsuchida, H.
2009-01-01
We investigated molecular fragmentation of C 2 H 4 in charge-changing collisions of 1.14MeV O 2+ ions. Branching ratios associated with decaying from temporary produced (C 2 H 4 ) r+ ions into various fragment channels were obtained. Dissociation via a C-C bond breaking is preferential in 1-electron loss collisions in comparison with 1-electron capture collisions. We confirmed that multiple ionization and dissociation rarely occur in electron capture collisions, while they occur rather strongly in electron loss collisions. (author)
International Nuclear Information System (INIS)
Legendre, S; Maisonny, R; Capron, M; Bernigaud, V; Cassimi, A; Gervais, B; Grandin, J-P; Huber, B A; Manil, B; Rousseau, P; Tarisien, M; Adoui, L; Lopez-Tarifa, P; AlcamI, M; MartIn, F; Politis, M-F; Penhoat, M A Herve du; Vuilleumier, R; Gaigeot, M-P; Tavernelli, I
2009-01-01
We study dissociative ionization of water clusters by impact of fast Ni ions. Cold Target Recoil Ion Momentum Spectroscopy (COLTRIMS) is used to obtain information about stability, energetics and charge mobility of the ionized clusters. An unusual stability of the (H 2 O) 4 H ''+ ion is observed, which could be the signature of the so called ''Eigen'' structure in gas phase water clusters. High charge mobility, responsible for the formation of protonated water clusters that dominate the mass spectrum, is evidenced. These results are supported by CPMD and TDDFT simulations, which also reveal the mechanisms of such mobility.
International Nuclear Information System (INIS)
Perlt, H.
1980-01-01
Scale breaking quark and gluon fragmentation functions obtained by solving numerically Altarelli-Parisi type equations are presented. Analytical parametrizations are given for the fragmentation of u and d quarks into pions. The calculated Q 2 dependent fragmentation functions are compared with experimental data. With these scale breaking fragmentation functions the average charged multiplicity is calculated in e + e - annihilation, which rises with energy more than logarithmically and is in good agreement with experiment. (author)
International Nuclear Information System (INIS)
Cobb, J.H.; Allison, W.W.M.; Bunch, J.N.
1976-01-01
A brief review shows a significant discrepancy between available data and theoretical predictions on the ionisation loss of charged particles in thin gas-filled proportional counters. The discrepancy related both to the increase of the most probable loss at relativistic velocities (relativistic rise) and to the spectrum of such losses at a given velocity (the Landau distribution). The origin of this relativistic rise is discussed in simple terms and related to the phenomena of transition radiation and Cherenkov radiation. It is shown that the failure of the prediction is due to the small number of ionising collisions in a gas. This problem is overcome by using a Monte Carlo method rather than a continuous integral over the spectrum of single collision processes. A specific mode of the atomic form factors is used with a modified Born approximation to yield the differential cross sections needed for the calculation. The new predictions give improved agreement with experiment and are used to investigate the problem of identifying particles of known momenta in the relativistic region. It is shown that by measuring the ionisation loss of each particle several hundred times over 5m or more, kaon, pion and proton separation with good confidence level may be achieved. Many gases are considered and a comparison is made. The results are also compared with the velocity resolution achievable by measuring primary ionisation. (Auth.)
International Nuclear Information System (INIS)
Ghaffary, Tooraj
2016-01-01
By the use of data from the annihilation process of electron-positron in AMY detector at 60 GeV center of mass energy, charged particles multiplicity distribution is obtained and fitted with the KNO scaling. Then, momentum spectra of charged particles and momentum distribution with respect to the jet axis are obtained, and the results are compared to the different models of QCD; also, the distribution of fragmentation functions and scaling violations are studied. It is being expected that the scaling violations of the fragmentation functions of gluon jets are stronger than the quark ones. One of the reasons for such case is that splitting function of quarks is larger than splitting function of gluon.
Yang, HongJiang; Wang, Enliang; Dong, WenXiu; Gong, Maomao; Shen, Zhenjie; Tang, Yaguo; Shan, Xu; Chen, Xiangjun
2018-05-01
The a b i n i t i o molecular dynamics (MD) simulations using an atom-centered density matrix propagation method have been carried out to investigate the fragmentation of the ground-state triply charged carbon dioxide, CO23 +→C+ + Oa+ + Ob+ . Ten thousands of trajectories have been simulated. By analyzing the momentum correlation of the final fragments, it is demonstrated that the sequential fragmentation dominates in the three-body dissociation, consistent with our experimental observations which were performed by electron collision at impact energy of 1500 eV. Furthermore, the MD simulations allow us to have detailed insight into the ultrafast evolution of the molecular bond breakage at a very early stage, within several tens of femtoseconds, and the result shows that the initial nuclear vibrational mode plays a decisive role in switching the dissociation pathways.
Arzeliès, Henri
1972-01-01
Relativistic Point Dynamics focuses on the principles of relativistic dynamics. The book first discusses fundamental equations. The impulse postulate and its consequences and the kinetic energy theorem are then explained. The text also touches on the transformation of main quantities and relativistic decomposition of force, and then discusses fields of force derivable from scalar potentials; fields of force derivable from a scalar potential and a vector potential; and equations of motion. Other concerns include equations for fields; transfer of the equations obtained by variational methods int
Motion of the relativistic charged particle in an axisymmetric toroidal system
Energy Technology Data Exchange (ETDEWEB)
Chiyoda, K; Sugimoto, H [Electrotechnical Labs., Sakura, Ibaraki (Japan)
1980-01-01
The relativistic theory of motion of one particle by Morozov and Solov'ev is summarized for convenience of the present study. Then, a drift equation is given and four constants of motion, E/sub 0/, J perpendicular, J and J parallel, are obtained. These constants of motion are used in analyzing the particle motion in an axisymmetric toroidal system. The displacement of the particle from the magnetic surface, ..delta..r, and the period of the banana motion, tau, are obtained. The relativistic expressions of the displacement, ..delta..r, and the period, tau, are obtained by multiplying the corresponding nonrelativistic expressions by (1 - v parallel/sup 2//c/sup 2/) - 1/2, where the relativistic expression of ..delta..r includes the relativistic mass in terms of Larmor radius r/sub L/.
Ionization and fragmentation of water clusters by fast highly charged ions
International Nuclear Information System (INIS)
Adoui, L; Cassimi, A; Gervais, B; Grandin, J-P; Guillaume, L; Maisonny, R; Legendre, S; Tarisien, M; Lopez-Tarifa, P; Alcami, M; Martin, F; Politis, M-F; Penhoat, M-A Herve du; Vuilleumier, R; Gaigeot, M-P; Tavernelli, I
2009-01-01
We study the dissociative ionization of water clusters by impact of 12 MeV/u Ni 25+ ions. Cold target recoil ion momentum spectroscopy (COLTRIMS) is used to obtain information about stability, energetics and charge mobility of the ionized water clusters. An unusual stability of the H 9 O + 4 ion is observed, which could be the signature of the so-called Eigen structure in gas-phase water clusters. From the analysis of coincidences between charged fragments, we conclude that charge mobility is very high and is responsible for the formation of protonated water clusters, (H 2 O) n H + , that dominate the mass spectrum. These results are supported by Car-Parrinello molecular dynamics and time-dependent density functional theory simulations, which also reveal the mechanisms of such mobility.
International Nuclear Information System (INIS)
Ganguli, G.; Palmadesso, P.
1984-01-01
Finite geometry effects on the stability properties of a charged beam propagating through an intense relativistic annular electron beam have been studied. The stability of the system under transverse oscillation has been examined in detail in a parameter domain pertinent to the collective particle accelerator, currently under development at the Naval Research Laboratory. Both the normal mode and the convective aspects of this instability have been investigated. Despite a substantial temporal growth rate as predicted by the normal mode approach, this instability does not prevent successful acceleration of a portion of the axial beam. Thus the transverse oscillation is not fatal to the collective particle accelerator operation
Norbury, John W.
1992-01-01
Single nucleon removal in relativistic and intermediate energy nucleus-nucleus collisions is studied using a generalization of Weizsacker-Williams theory that treats each electromagnetic multipole separately. Calculations are presented for electric dipole and quadrupole excitations and incorporate a realistic minimum impact parameter, Coulomb recoil corrections, and the uncertainties in the input photonuclear data. Discrepancies are discussed. The maximum quadrupole effect to be observed in future experiments is estimated and also an analysis of the charge dependence of the electromagnetic cross sections down to energies as low as 100 MeV/nucleon is made.
Komathiraj, K.; Sharma, Ranjan
2018-05-01
In this paper, we present a formalism to generate a family of interior solutions to the Einstein-Maxwell system of equations for a spherically symmetric relativistic charged fluid sphere matched to the exterior Reissner-Nordström space-time. By reducing the Einstein-Maxwell system to a recurrence relation with variable rational coefficients, we show that it is possible to obtain closed-form solutions for a specific range of model parameters. A large class of solutions obtained previously are shown to be contained in our general class of solutions. We also analyse the physical viability of our new class of solutions.
International Nuclear Information System (INIS)
Bassi, A.; Donadi, S.
2014-01-01
We study the photon emission rate of a non-relativistic charged particle interacting with an external classical noise through its position. Both the particle and the electromagnetic field are quantized. Under only the dipole approximation, the equations of motion can be solved exactly for a free particle, or a particle bounded by an harmonic potential. The physical quantity we will be interested in is the spectrum of the radiation emitted by the particle, due to the interaction with the noise. We will highlight several properties of the spectrum and clarify some issues appearing in the literature, regarding the exact mathematical formula of a spectrum for a free particle.
Alexander, LYSENKO; Iurii, VOLK
2018-03-01
We developed a cubic non-linear theory describing the dynamics of the multiharmonic space-charge wave (SCW), with harmonics frequencies smaller than the two-stream instability critical frequency, with different relativistic electron beam (REB) parameters. The self-consistent differential equation system for multiharmonic SCW harmonic amplitudes was elaborated in a cubic non-linear approximation. This system considers plural three-wave parametric resonant interactions between wave harmonics and the two-stream instability effect. Different REB parameters such as the input angle with respect to focusing magnetic field, the average relativistic factor value, difference of partial relativistic factors, and plasma frequency of partial beams were investigated regarding their influence on the frequency spectrum width and multiharmonic SCW saturation levels. We suggested ways in which the multiharmonic SCW frequency spectrum widths could be increased in order to use them in multiharmonic two-stream superheterodyne free-electron lasers, with the main purpose of forming a powerful multiharmonic electromagnetic wave.
International Nuclear Information System (INIS)
Paar, N.; Vretenar, D.; Marketin, T.; Ring, P.
2008-01-01
Inclusive neutrino-nucleus cross sections are calculated using a consistent relativistic mean-field theoretical framework. The weak lepton-hadron interaction is expressed in the standard current-current form, the nuclear ground state is described with the relativistic Hartree-Bogoliubov model, and the relevant transitions to excited nuclear states are calculated in the relativistic quasiparticle random-phase approximation. Illustrative test calculations are performed for charged-current neutrino reactions on 12 C, 16 O, 56 Fe, and 208 Pb, and results compared with previous studies and available data. Through the use of the experimental neutrino fluxes, the averaged cross sections are evaluated for nuclei of interest for neutrino detectors. We analyze the total neutrino-nucleus cross sections and the evolution of the contribution of the different multipole excitations as a function of neutrino energy. The cross sections for reactions of supernova neutrinos on 16 O and 208 Pb target nuclei are analyzed as functions of the temperature and chemical potential
International Nuclear Information System (INIS)
Harman, Z.; Artemyev, A.N.; Crespo Lopez-Urrutia, J.R.
2008-01-01
Dielectronic recombination and visible emission spectra are investigated theoretically and experimentally. Spectra of x-rays emitted from electron beam ion trap plasmas allow the study of correlation and quantum electrodynamic effects in relativistic few-body systems. In the visible range, exploring the forbidden M1 transitions in Be- and B-like argon ions provides one new insights into the relativistic modelling of isotope shift effects and extend the scope of bound-electron g factor measurements to few-electron ions. (author)
Harris, Christopher; Stace, Anthony J
2018-03-15
A series of experiments have been undertaken on the fragmentation of multiply charged ammonia clusters, (NH 3 ) n z+ , where z ≤ 8 and n ≤ 850, to establish Rayleigh instability limits, whereby clusters at certain critical sizes become unstable due to Coulomb repulsion between the resident charges. Experimental results on size-selected clusters are found to be in excellent agreement with theoretical predictions of Rayleigh instability limits at all values of the charge. Electrostatic theory has been used to help identify fragmentation patterns on the assumption that the clusters separate into two dielectric spheres, and the predicted Coulomb repulsion energies used to establish pathways and the sizes of cluster fragments. The results show that fragmentation is very asymmetric in terms of both the numbers of molecules involved and the amount of charge each fragment accommodates. For clusters carrying a charge ≤+4, the results show that fragmentation proceeds via the loss of small, singly charged clusters. When clusters carry a charge of +5 or more, the experimental observations suggest a marked switch in behavior. Although the laboratory measurements equate to fragmentation via the loss of a large dication cluster, electrostatic theory supports an interpretation that involves the sequential loss of two smaller, singly charged clusters possibly accompanied by the extensive evaporation of neutral molecules. It is suggested that this change in fragmentation pattern is driven by the channelling of Coulomb repulsion energy into intermolecular modes within these larger clusters. Overall, the results appear to support the ion evaporation model that is frequently used to interpret electrospray experiments.
Hwang, Sang-Yeon; Kim, Jaewook; Kim, Woo Youn
2018-04-04
In theoretical charge-transfer research, calculation of the electronic coupling element is crucial for examining the degree of the electronic donor-acceptor interaction. The tunneling current (TC), representing the magnitudes and directions of electron flow, provides a way of evaluating electronic couplings, along with the ability of visualizing how electrons flow in systems. Here, we applied the TC theory to π-conjugated organic dimer systems, in the form of our fragment-orbital tunneling current (FOTC) method, which uses the frontier molecular-orbitals of system fragments as diabatic states. For a comprehensive test of FOTC, we assessed how reasonable the computed electronic couplings and the corresponding TC densities are for the hole- and electron-transfer databases HAB11 and HAB7. FOTC gave 12.5% mean relative unsigned error with regard to the high-level ab initio reference. The shown performance is comparable with that of fragment-orbital density functional theory, which gave the same error by 20.6% or 13.9% depending on the formulation. In the test of a set of nucleobase π stacks, we showed that the original TC expression is also applicable to nondegenerate cases under the condition that the overlap between the charge distributions of diabatic states is small enough to offset the energy difference. Lastly, we carried out visual analysis on the FOTC densities of thiophene dimers with different intermolecular alignments. The result depicts an intimate topological connection between the system geometry and electron flow. Our work provides quantitative and qualitative grounds for FOTC, showing it to be a versatile tool in characterization of molecular charge-transfer systems.
International Nuclear Information System (INIS)
Almaliev, A.N.; Batkin, I.S.; Kopytin, I.V.
1987-01-01
The process of exciting atoms and atomic nuclei by relativistic electrons and positrons bound in a one-dimensional potential is investigated theoretically. It is shown that a pole corresponding to the emergence of a virtual photon on a bulk surface occurs in the matrix interaction element under definite kinematic relationships. It is obtained that the probability of the excitation process depends on the lifetime of the level being excited, the virtual photon, and the charged particle in a definite energetic state. An estimate of the magnitude of the excitation section of low-lying nuclear states yields a value exceeding by several orders the section obtained for charged particles in the absence of a binding potential
International Nuclear Information System (INIS)
Lin, M. C.; Lu, P. S.; Chang, P. C.; Ragan-Kelley, B.; Verboncoeur, J. P.
2014-01-01
Recently, field emission has attracted increasing attention despite the practical limitation that field emitters operate below the Child-Langmuir space charge limit. By introducing counter-streaming ion flow to neutralize the electron charge density, the space charge limited field emission (SCLFE) current can be dramatically enhanced. In this work, we have developed a relativistic self-consistent model for studying the enhancement of SCLFE by a counter-streaming ion current. The maximum enhancement is found when the ion effect is saturated, as shown analytically. The solutions in non-relativistic, intermediate, and ultra-relativistic regimes are obtained and verified with 1-D particle-in-cell simulations. This self-consistent model is general and can also serve as a benchmark or comparison for verification of simulation codes, as well as extension to higher dimensions
Energy Technology Data Exchange (ETDEWEB)
Loveland, W.D.
1991-08-01
The work described herein is part of a project involving the study of low energy (< 10 MeV/A), intermediate energy (10--100 MeV/A) and relativistic (> 250 MeV/A) heavy ion reactions. In the low energy regime, we published a monograph on the properties of the heaviest elements and used that publication as a basis for making a set of ``best`` semi-empirical predictions of heavy element decay properties. The intermediate energy research effort focussed upon the completion of studies already begun and the initiation of a number of new experiments. In our study of a interaction of 21 MeV/nucleon {sup 129}Xe with {sup 197}Au, we compared the characteristics of the observed deep inelastic phenomena with various models of dissipative reactions and found significant discrepancies between observations and predictions. These discrepancies seemed to be caused by an improper treatment of pre-equilibrium in the early stages of the collision. In our study of the relativistic interaction of 400 MeV/nucleon {sup 12}C with {sup 197}Au, we reported the first direct physical measurement of the properties of the spallation residues from a nucleus-nucleus collision. We found the residue energies to be much lower than those predicted by the intranuclear cascade model, indicating some substantial modifications of that model are needed. But, we also found, indications of significant, non-zero values of the residue transverse momentum, a finding that calls into question the interpretation of a number of radiochemical recoil studies of the kinematics of high energy reactions. A program of performing numerical simulations of intermediate and high energy nuclear collisions using the QMD model was initiated.
Energy Technology Data Exchange (ETDEWEB)
Typel, S; Wolter, H H [Sektion Physik, Univ. Muenchen, Garching (Germany)
1998-06-01
Nuclear matter and ground state properties for (proton and neutron) semi-closed shell nuclei are described in relativistic mean field theory with coupling constants which depend on the vector density. The parametrization of the density dependence for {sigma}-, {omega}- and {rho}-mesons is obtained by fitting to properties of nuclear matter and some finite nuclei. The equation of state for symmetric and asymmetric nuclear matter is discussed. Finite nuclei are described in Hartree approximation, including a charge and an improved center-of-mass correction. Pairing is considered in the BCS approximation. Special attention is directed to the predictions for properties at the neutron and proton driplines, e.g. for separation energies, spin-orbit splittings and density distributions. (orig.)
Mišković, Zoran L.; Akbari, Kamran; Segui, Silvina; Gervasoni, Juana L.; Arista, Néstor R.
2018-05-01
We present a fully relativistic formulation for the energy loss rate of a charged particle moving parallel to a sheet containing two-dimensional electron gas, allowing that its in-plane polarization may be described by different longitudinal and transverse conductivities. We apply our formulation to the case of a doped graphene layer in the terahertz range of frequencies, where excitation of the Dirac plasmon polariton (DPP) in graphene plays a major role. By using the Drude model with zero damping we evaluate the energy loss rate due to excitation of the DPP, and show that the retardation effects are important when the incident particle speed and its distance from graphene both increase. Interestingly, the retarded energy loss rate obtained in this manner may be both larger and smaller than its non-retarded counterpart for different combinations of the particle speed and distance.
Absolute Charge Transfer and Fragmentation Cross Sections in He2+-C60 Collisions
International Nuclear Information System (INIS)
Rentenier, A.; Moretto-Capelle, P.; Bordenave-Montesquieu, D.; Bordenave-Montesquieu, A.; Ruiz, L. F.; Diaz-Tendero, S.; Alcami, M.; Martin, F.; Zarour, B.; Hanssen, J.; Hervieux, P.-A.; Politis, M. F.
2008-01-01
We have determined absolute charge transfer and fragmentation cross sections in He 2+ +C 60 collisions in the impact-energy range 0.1-250 keV by using a combined experimental and theoretical approach. We have found that the cross sections for the formation of He + and He 0 are comparable in magnitude, which cannot be explained by the sole contribution of pure single and double electron capture but also by contribution of transfer-ionization processes that are important even at low impact energies. The results show that multifragmentation is important only at impact energies larger than 40 keV; at lower energies, sequential C 2 evaporation is the dominant process
Anomalies in the Charge Yields of Fission Fragments from the ^{238}U(n,f) Reaction.
Wilson, J N; Lebois, M; Qi, L; Amador-Celdran, P; Bleuel, D; Briz, J A; Carroll, R; Catford, W; De Witte, H; Doherty, D T; Eloirdi, R; Georgiev, G; Gottardo, A; Goasduff, A; Hadyńska-Klęk, K; Hauschild, K; Hess, H; Ingeberg, V; Konstantinopoulos, T; Ljungvall, J; Lopez-Martens, A; Lorusso, G; Lozeva, R; Lutter, R; Marini, P; Matea, I; Materna, T; Mathieu, L; Oberstedt, A; Oberstedt, S; Panebianco, S; Podolyák, Zs; Porta, A; Regan, P H; Reiter, P; Rezynkina, K; Rose, S J; Sahin, E; Seidlitz, M; Serot, O; Shearman, R; Siebeck, B; Siem, S; Smith, A G; Tveten, G M; Verney, D; Warr, N; Zeiser, F; Zielinska, M
2017-06-02
Fast-neutron-induced fission of ^{238}U at an energy just above the fission threshold is studied with a novel technique which involves the coupling of a high-efficiency γ-ray spectrometer (MINIBALL) to an inverse-kinematics neutron source (LICORNE) to extract charge yields of fission fragments via γ-γ coincidence spectroscopy. Experimental data and fission models are compared and found to be in reasonable agreement for many nuclei; however, significant discrepancies of up to 600% are observed, particularly for isotopes of Sn and Mo. This indicates that these models significantly overestimate the standard 1 fission mode and suggests that spherical shell effects in the nascent fission fragments are less important for low-energy fast-neutron-induced fission than for thermal neutron-induced fission. This has consequences for understanding and modeling the fission process, for experimental nuclear structure studies of the most neutron-rich nuclei, for future energy applications (e.g., Generation IV reactors which use fast-neutron spectra), and for the reactor antineutrino anomaly.
Czech Academy of Sciences Publication Activity Database
Shulyapov, S. A.; Mordvintsev, I. M.; Ivanov, K. A.; Volkov, P. V.; Zarubin, P. I.; Ambrožová, Iva; Turek, Karel; Savelyev, A. B.
2016-01-01
Roč. 46, č. 5 (2016), s. 432-436 ISSN 1063-7818 Institutional support: RVO:61389005 Keywords : relativistic intensity * contrast * laser plasma * ion acceleration * multiply charged ions * collision ionisation Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.119, year: 2016
International Nuclear Information System (INIS)
Maslyuk, V.T.
2012-01-01
A new approach to the problem of nucleosynthesis based on assumption of a nuclear matter or superheavy nuclei series fragmentation up to atomic nuclei is proposed. It is shown that studies of the mass (charge) fragments yields (MCFY) after nuclear matter disintegration is possible within proposed statistical theory. The data of MCFY calculation for exotic superheavy nuclei multifragmentation with A=300, 900 and 1200 and arbitrary Z values are demonstrated
The search for highly relativistic broken-charge particles in the cosmic radiation
International Nuclear Information System (INIS)
Krisor, K.
1974-01-01
As an introduction, the quark model of the elementary particles and the present state of the quark search is gone into. The theory of the energy loss of charged particles in the passage through matter and the set-up of the experiment (proportional counter hodoscope, electronics, on-line computer and off-line analysis of the data) are dealt with in detail. The following upper limits are given with 90% confidence: charge 1/3e -11 cm -2 sr -1 s -1 charge 2/3e -11 cm -2 sr -1 s -1 for the flow of unaccompanied quarks at sea level. (BJ/LH) [de
Causal electric charge diffusion and balance functions in relativistic heavy-ion collisions
Kapusta, Joseph I.; Plumberg, Christopher
2018-01-01
We study the propagation and diffusion of electric charge fluctuations in high-energy heavy-ion collisions using the Cattaneo form for the dissipative part of the electric current. As opposed to the ordinary diffusion equation this form limits the speed at which charge can propagate. Including the noise term in the current, which arises uniquely from the fluctuation-dissipation theorem, we calculate the balance functions for charged hadrons in a simple 1+1-dimensional Bjorken hydrodynamical model. Limiting the speed of propagation of charge fluctuations increases the height and reduces the width of these balance functions when plotted versus rapidity. We also estimate the numerical value of the associated diffusion time constant from anti-de Sitter-space/conformal-field theory.
Mechanism of 238U disintegration induced by relativistic particles
International Nuclear Information System (INIS)
Andronenko, L.N.; Zhdanov, A.A.; Kravtsov, A.V.; Solyakin, G.E.
2002-01-01
In heavy-nucleus disintegration induced by a relativistic projectile particle, the production of collinear massive fragments accompanied by numerous charged particles and neutrons is explained in terms of the mechanism of projectile-momentum compensation due to the emission of a particle whose mass is greater than the projectile mass
International Nuclear Information System (INIS)
Doornenbal, P.
2007-01-01
A two-step fragmentation experiment has been performed at GSI with the RISING setup. It combines the fragment separator FRS, which allows for the production of radioactive heavy ions at relativistic energies, with a high resolution γ-spectrometer. This combination offers unique possibilities for nuclear structure investigations like the test of shell model predictions far from stability. Within the present work the question if the N=14(16) shell stabilisation in Z=8 oxygen isotopes and the N=20 shell quenching in 32 Mg are symmetric with respect to the isospin projection quantum number Tz has been addressed. New γ-ray decays were found in the neutron deficient 36 Ca and 36 K by impinging a radioactive ion beam of 37 Ca on a secondary 9 Be target. The fragmentation products were selected with the calorimeter telescope CATE and the emitted γ-rays were measured with Ge Cluster, MINIBALL, and BaF 2 HECTOR detectors. For 36 Ca the 2 1 + →0 g.s. + transition energy was determined to be 3015(16) keV, which is the heaviest T=2 nucleus from which γ-spectroscopic information has been obtained so far. A comparison between the experimental 2 1 + energies of 36 Ca and its mirror nucleus 36 S yielded a mirror energy difference of ΔE M =-276(16) keV. In order to understand the large ΔE M value, the experimental single-particle energies from the A=17, T=1/2 mirror nuclei were taken and applied onto modified isospin symmetric USD interactions in shell model calculations. These calculations were in agreement with the experimental result and showed that the experimental single-particle energies may account empirically for the one body part of Thomas-Ehrman and/or Coulomb effects. A method to extract the lifetime of excited states in fragmentation reactions was investigated. Therefore, the dependence between the lifetime of an excited state and the average de-excitation velocity and trajectory of the nuclei in relativistic fragmentation experiments has been studied. Known
Energy Technology Data Exchange (ETDEWEB)
Doornenbal, P.
2007-10-23
A two-step fragmentation experiment has been performed at GSI with the RISING setup. It combines the fragment separator FRS, which allows for the production of radioactive heavy ions at relativistic energies, with a high resolution {gamma}-spectrometer. This combination offers unique possibilities for nuclear structure investigations like the test of shell model predictions far from stability. Within the present work the question if the N=14(16) shell stabilisation in Z=8 oxygen isotopes and the N=20 shell quenching in {sup 32}Mg are symmetric with respect to the isospin projection quantum number Tz has been addressed. New {gamma}-ray decays were found in the neutron deficient {sup 36}Ca and {sup 36}K by impinging a radioactive ion beam of {sup 37}Ca on a secondary {sup 9}Be target. The fragmentation products were selected with the calorimeter telescope CATE and the emitted {gamma}-rays were measured with Ge Cluster, MINIBALL, and BaF{sub 2} HECTOR detectors. For {sup 36}Ca the 2{sub 1}{sup +}{yields}0{sub g.s.}{sup +} transition energy was determined to be 3015(16) keV, which is the heaviest T=2 nucleus from which {gamma}-spectroscopic information has been obtained so far. A comparison between the experimental 2{sub 1}{sup +} energies of {sup 36}Ca and its mirror nucleus {sup 36}S yielded a mirror energy difference of {delta}E{sub M}=-276(16) keV. In order to understand the large {delta}E{sub M} value, the experimental single-particle energies from the A=17, T=1/2 mirror nuclei were taken and applied onto modified isospin symmetric USD interactions in shell model calculations. These calculations were in agreement with the experimental result and showed that the experimental single-particle energies may account empirically for the one body part of Thomas-Ehrman and/or Coulomb effects. A method to extract the lifetime of excited states in fragmentation reactions was investigated. Therefore, the dependence between the lifetime of an excited state and the average de
The charge form factor of pseudoscalar mesons in a relativistic constituent quark model
Energy Technology Data Exchange (ETDEWEB)
Cardarelli, F.; Pace, E. [Univ. of Rome, Roma (Italy); Grach, I.L. [Inst. of Theoretical and Experimental Physics, Moscow (Russian Federation)] [and others
1994-04-01
The charge form factor of pseudoscalar mesons has been investigated in the light-cone formalism, up to Q{sup 2} relevant to CEBAF energies. The consequences of adopting the meson wave functions generated through the Godfrey-Isgur q{bar q} potential, which reproduces the mass spectra, are discussed.
Fragment ion distribution in charge-changing collisions of 2-MeV Si ions with C60
Itoh, A.; Tsuchida, H.; Miyabe, K.; Majima, T.; Nakai, Y.
2001-09-01
We have measured positive fragment ions produced in collisions of 2 MeV Siq+ (q=0, 1, 2, 4) projectiles with a C60 molecular target. The measurement was performed with a time-of-flight coincidence method between fragment ions and charge-selected outgoing projectiles. For all the charge-changing collisions investigated here, the mass distribution of small fragment ions C+n (n=1-12) can be approximated fairly well by a power-law form of n-λ as a function of the cluster size n. The power λ derived from each mass distribution is found to change strongly according to different charge-changing collisions. As a remarkable experimental finding, the values of λ(loss) in electron loss collisions are almost the same for the same final charge states k irrespective of the initial charge q, exhibiting a nearly perfect linear relationship with k. We also performed calculations of the projectile ionization on the basis of the semiclassical approximation and obtained inelastic energy deposition for individual collision processes. The estimated energy deposition is found to have a simple correlation with the experimentally determined values of λ(loss).
Electromagnetically-induced nuclear-charge pickup observed in ultra-relativistic Pb collisions
International Nuclear Information System (INIS)
Scheidenberger, C.; Aumann, T.; Pshenichnov, I.A.; Russian Academy of Sciences, Moscow
2002-01-01
A strong increase of inclusive nuclear-charge pickup cross sections, forming 83 Bi from 158 A GeV 82 Pb ions, is observed in comparison to similar measurements at 10.6 A GeV. From the dependence of these cross sections on target atomic number, this increase is attributed to the electromagnetic process of pion production by equivalent photons. The observed cross sections can be reproduced quantitatively using the recently developed RELDIS code. (orig.)
Existence of charges and mass-spliting in relativistic quantum field theory
International Nuclear Information System (INIS)
Gal-Ezer, E.; Horwitz, L.P.
1976-01-01
The existence of charge operators associated with integrals of local densities in the (Wightman) framework of quantum field theory, in the presence of explicit symmetry breaking, can be demonstrated in certain cases. Their construction, in terms of null-plane integrals, is rather delicate. The possibility that a finite number of null-plane charges, which includes the Poincare generators, close on an algebra whose irreducible representations contain particles with different masses is considered; domain problems are shown to invalidate the basic hypotheses of the O'Raifeartaigh theorem. Null-plane Fourier transforms, which enter into the discussion of current algebra at infinite momentum, are also studied. It is shown that slns behavior is the maximal growth of high energy off mass shell amplitudes consistent with the existence of null-plane charges and null-plane Fourier transforms. Under the assumption that asymptotic states exist, these results also hold in the case of spontaneously broken chiral symmetry, with massless pseudoscalar Goldstone bosons
International Nuclear Information System (INIS)
Kobushkin, A.P.; Vizireva, L.
1981-01-01
A study of the nature of the short-range few-nucleon correlations in nuclei is proposed in the polarized high-energy deuteron fragmentation experiments. The presence of 6q-state in deuteron with probability of several percents is shown to change essentially the cross-section behaviour of this process in the momentum region where the fraction of the deuteron momentum carried out by proton in the infinite momentum frame is about 0.78. It is shown how the character of the cross-section of the transverse polarized deuteron fragmentation is changed depending on the parameters of 6q-admixure in deuteron [ru
Onengüt, G; De Jong, M; Konijn, J; Melzer, O; Oldeman, R G C; Pesen, E; Van der Poel, C A F J; Visschers, J L; Güler, M; Köse, U; Serin-Zeyrek, M; Kama, S; Sever, R; Tolun,, P; Zeyrek, M T; Catanesi, M G; De Serio, M; Ieva, M; Muciaccia, M T; Radicioni, E; Simone, S; Bülte, A; Winter, Klaus; Van de Vyver, B; Vilain, P; Wilquet, G; Saitta, B; Di Capua, E; Ogawa, S; Shibuya, H; Artamonov, A V; Brunner, J; Chizhov, M; Cussans, D G; Doucet, M; Fabre, Jean-Paul; Hristova, I R; Kawamura, T; Kolev, D; Litmaath, M; Meinhard, H; Panman, J; Papadopoulos, I M; Ricciardi, S; Rozanov, A; Saltzberg, D; Tsenov, R V; Uiterwijk, J W E; Zucchelli, P; Goldberg, J; Chikawa, M; Arik, E; Song, J S; Yoon, C S; Kodama, K; Ushida, N; Aoki, S; Hara, T; Delbar, T; Favart, D; Grégoire, G; Kalinin, S; Makhlyoueva, I V; Gorbunov, P; Khovanskii, V D; Shamanov, V V; Tsukerman, I; Bruski, N; Frekers, D; Rondeshagen, D; Wolff, T; Hoshino, K; Kawada, J; Komatsu, M; Miyanishi, M; Nakamura, M; Nakano, T; Narita, K; Niu, K; Niwa, K; Nonaka, N; Sato, O; Toshito, T; Buontempo, S; Cocco, A G; D'Ambrosio, N; De Lellis, G; De Rosa, G; Di Capua, F; Ereditato, A; Fiorillo, G; Marotta, A; Messina, M; Migliozzi, P; Pistillo, C; Santorelli, R; Scotto-Lavina, L; Strolin, P; Tioukov, V; Nakamura, K; Okusawa, T; Dore, U; FLoverre, P; Ludovici, L; Maslennikov, A L; Righini, P; Rosa, G; Santacesaria, R; Satta, A; Spada, F R; Barbuto, E; Bozza, C; Grella, G; Romano, G; Sirignano, C; Sorrentino, S; Sato, Y; Tezuka, I
2004-01-01
During the years 1994-97, the emulsion target of the CHORUS detector was exposed to the wideband neutrino beam of the CERN SPS. In total about 100 000 charged-current neutrino interactions were located in the nuclear emulsion target and fully reconstructed. From this sample of events which was based on the data acquired by new automatic scanning systems, 1048 D0 events were selected by a pattern recognition program. They were confirmed as neutral-particle decays through visual inspection. Fragmentation properties of deep-inelastic charm production were measured using these events. Distributions of the D0 momentum, Feynman x(x_F), z and tan thetaôut, the transverse angle out of the leptonic plane defined by the muon and the neutrino, are presented. The mean value of z was measured to be (z) = 0.63 +- 0.03(stat) +- 0.01(syst). From fits to the z distribution, values for the Peterson parameter epsilon_p = 0.108 +- 0.017(stat) +- 0.013(syst) and the Collins-Spiller parameter epsilon_CS = 0.21^+0.05_-0.04(stat) +...
International Nuclear Information System (INIS)
Xu, Peng; Gordon, Mark S.
2013-01-01
The charge transfer (CT) interaction, the most time-consuming term in the general effective fragment potential method, is made much more computationally efficient. This is accomplished by the projection of the quasiatomic minimal-basis-set orbitals (QUAMBOs) as the atomic basis onto the self-consistent field virtual molecular orbital (MO) space to select a subspace of the full virtual space called the valence virtual space. The diagonalization of the Fock matrix in terms of QUAMBOs recovers the canonical occupied orbitals and, more importantly, gives rise to the valence virtual orbitals (VVOs). The CT energies obtained using VVOs are generally as accurate as those obtained with the full virtual space canonical MOs because the QUAMBOs span the valence part of the virtual space, which can generally be regarded as “chemically important.” The number of QUAMBOs is the same as the number of minimal-basis MOs of a molecule. Therefore, the number of VVOs is significantly smaller than the number of canonical virtual MOs, especially for large atomic basis sets. This leads to a dramatic decrease in the computational cost
A time-of-flight system for precise measurements of a relativistic charged particle beam momentum
International Nuclear Information System (INIS)
Avramenko, S.A.; Belikov, Yu.A.; Golokhvastov, A.I.; Lukstin'sh, Yu.; Man'yakov, P.K.; Rukoyatkin, P.A.; Khorozov, S.A.
1996-01-01
A time-of-flight system with a time resolution (σ) about 100 ps is described. The methods for the calibration, stability verification and the method for the time resolution evaluation in conditions of a nonmonochromatic beam are discussed especially. The system was applied in charge exchange ( 3 H, 3 He) experiments with the GIBS spectrometer for a measurement of 3 H-nuclei momenta at 2 GeV/c per nucleon with a precision about 0.2%. (author). 4 refs., 7 figs., 1 tab
International Nuclear Information System (INIS)
Bernigaud, V.
2009-01-01
This thesis concerns a gas phase study of the fragmentation of bio-molecular systems induced by slow collisions with multiply charged ions (in the keV-region), alkali atoms and rare gases. The main objective was to study the physical processes involved in the dissociation of highly electronically excited systems. In order to elucidate the intrinsic properties of certain biomolecules (porphyrins and amino acids) we have performed experiments in the gas phase with isolated systems. The obtained results demonstrate the high stability of porphyrins after electron removal and attachment. Furthermore, a dependence of the fragmentation pattern produced by multiply charged ions on the isomeric structure of the alanine molecule has been shown. In a second part of the thesis, a strong influence of the environment of the biomolecule on the fragmentation channels, their modification and their new opening, has been clearly proven. This phenomenon occurs in the presence of other surrounding biomolecules (clusters of nucleobases) as well as for molecules of a solvent (molecules of water, methanol and acetonitrile) in which the biomolecule is embedded. In order to extend these studies to larger systems, a new experimental set-up, based on an electro-spray ion source combined with a quadrupole mass filter has been developed. Due to the successful tests and proposed improvements of the device future experiments will become available concerning the fragmentation of large charged and solvated bio-molecular systems induced by collision processes. (author) [fr
International Nuclear Information System (INIS)
Blank, B.
1991-06-01
In the framework of this thesis the method of the 'momentum-loss achromate' was for the first time tested at relativistic energies. This experiment is presented in chapter 2 of the thesis. In a second experiment the method was then used, in order to make secondary beams of 8,9,11 Li available. With these secondary beams cross section measurements were performed, from which beside information on the nuclear radii of these nuclei also further information on the internal structure of the lithium isotopes can be derived. This experiment is described in chapter 3 of the thesis. In the framework of these two experiments for the applied heavy ions energy-loss measurements were performed. The results of these measurements are presented in chapter 4. (orig.) [de
Energy Technology Data Exchange (ETDEWEB)
Ayet San Andres, Samuel [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Justus Liebig Universitaet, Giessen (Germany); Collaboration: FRS Ion Catcher-Collaboration
2016-07-01
At the FRS Ion Catcher at GSI, a relativistic beam of {sup 238}U at 1GeV/u was used to produce fission and projectile fragments on a beryllium target. The ions were separated in-flight at the FRS, thermalized in a cryogenic stopping cell and transferred to a multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS) where high precision mass measurements were performed. The masses of several fission and projectile fragments were measured (including short-lived nuclei with half-lives down to 18 ms) and the possibility of tailoring an isomerically clean beam for other experiments was demonstrated. With the demonstrated performance of the MR-TOF-MS and the expected production rates of exotic nuclei far from stability at the next-generation facilities such as FAIR, novel mass measurements of nuclei close to the neutron drip line will be possible and key information for understanding the r-process will be available. The results from the last experiment and an outlook of possible future mass measurements close to the neutron drip line at FAIR with the MR-TOF-MS are presented.
International Nuclear Information System (INIS)
Gomez R, F.
2004-01-01
In the chapter 1 we show the foundations of the special relativity in the frame of the classical mechanics and we develop the necessary theory for the theoretical description of the relativistic dynamics of charged particles in the interaction with electromagnetic fields. It will see that starting from the energy conservation principle is derived the Einstein's law that establishes the relationship among this and the mass. Later on, it will take the action of a charged particle in a given radiation field and in the one which only we will take two parts, the action of the free particle and the one that defines the interaction of this with the field. The equations of motion of a charge in an electromagnetic field come given by the Lagrange equations, being obtained an expression for the force, well-known as Lorentz force, which consists of two terms, the first of them is the force that the electric field E exercises on the particle; which doesn't depend on the charge speed and is oriented in the direction of the field, the second term represents the force that exercises the magnetic field B and that it is proportional to the charge speed, being perpendicular to the direction of it. In the chapter 2 an integration method of the Hamilton-Jacobi for the case of a pulse is that allows to found analytical forms for the moment, the energy and the charge position is developed with detail. We will present, also, a discussion of the classical theory of the relativistic dynamic of free electrons. They are also obtained, invariant quantities like the phase, before the frame of the reference inertial changes, well-known as Lorentz invariants of the system. In this part it is considered to the electron in the laboratory frame (frame in which the particle is initially in repose regarding the observer), of which the speed and the acceleration quadrivectors can be calculated. We demonstrate that the η phase is a Lorentz invariant. It is shown, also that the proper time interval d
Energy Technology Data Exchange (ETDEWEB)
Ibnouzahir, M
1995-03-01
The study of relativistic heavy ion collisions permit an approach of the properties of dense and not hadronic matter, and an analysis of the reaction mechanisms. Such studies are also interesting on the biological point of view, since there exist now well defined projects concerning the radiotherapy with high LET particles as neutrons, protons, heavy ions. It is thus necessary to have a good understanding of the processes which occur in the propagation of a relativistic heavy ion beam (E{>=} 100 A.MeV) in matter. We have elaborated a three dimensional transport code, using a Monte Carlo method, in order to describe the propagation of Ne and Ar ions in water. Violent nuclear collisions giving fragmentation process have been taken into account by use of the FREESCO program. We have tested the validity of our transport model and we show an important change of the energy deposition at the vicinity of the Bragg peak; such a distortion, due mainly to fragmentation reactions, is of a great interest for biological applications. (author).
Neutron fragmentation and inclusive charge exchange in pd and π+d interactions at 195 GeV/c
International Nuclear Information System (INIS)
Eisenberg, Y.; Haber, B.; Hochman, D.; Koller, E.; Ronat, E.E.; Shapira, A.; Yaari, R.; Yekutieli, G.; Braun, H.; Etienne, F.; Fridman, A.; Gerber, J.P.; Jegham, E.; Juillot, P.; Maurer, G.; Voltolini, C.
1977-01-01
An excess of negative particles and depletion of positive particles in the backward hemisphere (c.m. system) is observed in π + and p interactions on neutron target. dsigma - /dy is compared with pp interactions and the difference is related to the slow-proton spectrum produced in the pn interactions. A neutron fragmentation component is observed, and the inclusive charge-exchange probability at the nucleon vertex is found to be about 0.4
Neutron fragmentation and inclusive charge exchange in pd and π+d interactions at 195 GeV/c
International Nuclear Information System (INIS)
Eisenberg, Y.; Haber, B.; Hochman, D.; Koller, E.; Ronat, E.E.; Shapira, A.; Yaari, R.; Yekutieli, G.; Braun, H.; Etienne, F.; Fridman, A.; Gerber, J.P.; Jegham, E.; Juillot, P.; Maurer, G.; Voltolini, C.
1976-01-01
An excess of negative particles and depletion of positives in the cms backward hemisphere is observed in π + and p interactions on neutron target. dΣ - /dy is compared with pp interactions and the difference is related to the slow proton spectrum produced in the pn interactions. A neutron fragmentation component is observed and the inclusive charge exchange probability at the nucleon vertex is found to be about 0.4. (author)
Energy Technology Data Exchange (ETDEWEB)
Reiter, Moritz Pascal
2015-07-01
High precision experiments and decay spectroscopy of exotic nuclei are of great interest for nuclear structure and nuclear astro-physics. They allow for studies of the nuclear structure far from stability, test of fundamental interactions and symmetries and give important input for the understanding of the nuclear synthesis in the universe. In the context of this work a second generation stopping cell for the low energy branch of the Super-FRS was commissioned at the FRS at GSI and significant improvements were made to the device. The prototype stopping cell is designed as a cryogenic stopping cell (CSC), featuring enhanced cleanliness and high area density. The CSC was brought into full operation and its performance characteristics were investigated including the maximal area density, extraction times, cleanliness and extraction efficiencies. In three commissioning experiments at the current GSI FRS facility in 2011, 2012 and 2014 up to 22 isotopes from 14 elements produced by in-flight projectile fragmentation and fission of {sup 238}U could be thermalized and extracted with high efficiency. For the first time projectile and fission fragmentation produced at 1000 MeV/u could be thermalized in a stopping cell and provided as a low-energy beam of high brilliance for high precision experiments. The technical improvements of the CSC, such as an improved RF carpet, new cryocooler-based cooling system, a monitoring system of the cleanliness and the high density operation, made it possible to thermalize heavy {sup 238}U projectile fragments with total efficiencies of about 20% in the 2014 experiment. In addition the improvements lead to an increase in the stability and reliability of the CSC and the performance of the CSC during online experiments at the FRS Ion Catcher showed that the utilized techniques are ready for the final CSC for the low-energy branch of the Super-FRS at FAIR. The CSC was operated with an area density of up to 6.3 mg/cm{sup 2} helium during
International Nuclear Information System (INIS)
Reiter, Moritz Pascal
2015-01-01
High precision experiments and decay spectroscopy of exotic nuclei are of great interest for nuclear structure and nuclear astro-physics. They allow for studies of the nuclear structure far from stability, test of fundamental interactions and symmetries and give important input for the understanding of the nuclear synthesis in the universe. In the context of this work a second generation stopping cell for the low energy branch of the Super-FRS was commissioned at the FRS at GSI and significant improvements were made to the device. The prototype stopping cell is designed as a cryogenic stopping cell (CSC), featuring enhanced cleanliness and high area density. The CSC was brought into full operation and its performance characteristics were investigated including the maximal area density, extraction times, cleanliness and extraction efficiencies. In three commissioning experiments at the current GSI FRS facility in 2011, 2012 and 2014 up to 22 isotopes from 14 elements produced by in-flight projectile fragmentation and fission of "2"3"8U could be thermalized and extracted with high efficiency. For the first time projectile and fission fragmentation produced at 1000 MeV/u could be thermalized in a stopping cell and provided as a low-energy beam of high brilliance for high precision experiments. The technical improvements of the CSC, such as an improved RF carpet, new cryocooler-based cooling system, a monitoring system of the cleanliness and the high density operation, made it possible to thermalize heavy "2"3"8U projectile fragments with total efficiencies of about 20% in the 2014 experiment. In addition the improvements lead to an increase in the stability and reliability of the CSC and the performance of the CSC during online experiments at the FRS Ion Catcher showed that the utilized techniques are ready for the final CSC for the low-energy branch of the Super-FRS at FAIR. The CSC was operated with an area density of up to 6.3 mg/cm"2 helium during online
Energy Technology Data Exchange (ETDEWEB)
Bondarenko, S.; Prygarin, A. [Ariel University, Physics Department, Ariel (Israel); Lipatov, L. [St. Petersburg Nuclear Physics Institute, Saint Petersburg (Russian Federation); Hamburg University, II Institute of Theoretical Physics, Hamburg (Germany)
2017-08-15
We discuss application of formalism of small-x effective action for reggeized gluons (Gribov, Sov. Phys. JETP 26:414, 1968; Lipatov, Nucl. Phys. B 452:369, 1995; Lipatov, Phys. Rep. 286:131, 1997; Lipatov, Subnucl. Ser. 49:131, 2013; Lipatov, Int. J. Mod. Phys. Conf. Ser. 39:1560082, 2015; Lipatov, Int. J. Mod. Phys. A 31(28/29):1645011, 2016; Lipatov, EPJ Web Conf. 125:01010, 2016; Lipatov, Sov. J. Nucl. Phys. 23:338, 1976; Kuraev et al., Sov. Phys. JETP 45:199, 1977; Kuraev et al., Zh Eksp, Teor. Fiz. 72:377, 1977; Balitsky and Lipatov, Sov. J. Nucl. Phys. 28:822, 1978; Balitsky and Lipatov, Yad. Fiz. 28:1597 1978), for the calculation of classical gluon field of relativistic color charge, similarly to that done in CGC approach of McLerran and Venugopalan, Phys. Rev. D 49:2233 (1994), Jalilian-Marian et al., Phys. Rev. D 55:5414 (1997), Jalilian-Marian et al., Nucl. Phys. B 504:415 (1997), Jalilian-Marian et al., Phys. Rev. D 59:014014 (1998), Jalilian-Marian et al., Phys. Rev. D 59:014015 (1998), Iancu et al., Nucl. Phys. A 692:583 (2001), Iancu et al., Phys. Lett. B 510:133 (2001), Ferreiro et al., Nucl. Phys. A 703:489 (2002). The equations of motion with the reggeon fields are solved in LO and NLO approximations and new solutions are found. The results are compared to the calculations performed in the CGC framework and it is demonstrated that the LO CGC results for the classical field are reproduced in our calculations. Possible applications of the NLO solution in the effective action and CGC frameworks are discussed as well. (orig.)
Fragmentation of organic ions bearing fixed multiple charges observed in MALDI MS
Lou, X.; Li, B.; de Waal, B.F.M.; Schill, J.; Baker, M.B.; Bovee, R.A.A.; van Dongen, J.L.J.; Milroy, L.G.; Meijer, E.W.
2018-01-01
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS) was used to analyze a series of synthetic organic ions bearing fixed multiple charges. Despite the multiple intrinsic charges, only singly charged ions were recorded in each case. In addition to the
Cydzik, Marzena; Rudowska, Magdalena; Stefanowicz, Piotr; Szewczuk, Zbigniew
2011-12-01
Derivatization of peptides as quaternary ammonium salts (QAS) is a promising method for sensitive detection by electrospray ionization tandem mass spectrometry (Cydzik et al. J. Pept. Sci. 2011, 17, 445-453). The peptides derivatized by QAS at their N-termini undergo fragmentation according to the two competing mechanisms - charge remote (ChR) and charge directed (ChD). The absence of mobile proton in the quaternary salt ion results in ChR dissociation of a peptide bond. However, Hofmann elimination of quaternary salt creates an ion with one mobile proton leading to the ChD fragmentation. The experiments on the quaternary ammonium salts with deuterated N-alkyl groups or amide NH bonds revealed that QAS derivatized peptides dissociate according to the mixed ChR-ChD mechanism. The isotopic labeling allows differentiation of fragments formed according to ChR and ChD mechanisms. © The Author(s) 2011. This article is published with open access at Springerlink.com
Energy Technology Data Exchange (ETDEWEB)
Kelkar, A H; Misra, D; Tribedi, L C [Tata Institute of Fundamental Research, Colaba, Mumbai -5 (India)
2007-09-15
We study the various inelastic processes such ionization, fragmentation and evaporation of C{sub 60} molecule in collisions with fast heavy ions. We have used 2.33 MeV/u C, O and F projectile ion beams. Various ionization and fragmentation products were detected using time-of-flight mass spectrometer. The multiply charged C{sub 60}{sup r+} ions were detected for maximum r = 4. The projectile charge state (q{sub p}) dependence of the single and double ionization cross sections is well reproduced by a model based on the giant dipole plasmon resonance (GDPR). The q{sub p}-dependence of the fragmentation yields, was found to be linear. Variation of relative yields of the evaporation products of C{sub 60}{sup 2+} (i.e. C{sub 58}{sup 2+}, C{sub 56}{sup 2+} etc) and C{sub 60}{sup 3+} (i.e. C{sub 58}{sup 3+}, C{sub 56}{sup 3+} etc) with q{sub p} has also been investigated for various projectiles.
Extraction of Fragmentation Functions from Charged Kaon and Pion Production at COMPASS
Panknin, Regine Antje
Quark helicity distributions can be accessed by measuring spin asymmetries in polarised deep-inelastic scattering, but for a full flavour separation the precise knowledge of quark fragmentation functions is essential. Those can only be inf erred from experimental data, and are still poorly determined today. The few existing para metrisations of fragmentation functions are derived from world data (mainly on electron-positron annihilation), and often differ considerably, most notably for strange quarks. This thesis presents an independent evaluation of fragmentation functions from deep- inelastic scattering data recorded at the COMPASS experiment. A method of extraction was developed, based on the relation between hadron multiplicities, r h ( x, z ), unpolarised parton distribution functions, q ( x ), and quark fragmentation functions into hadrons, D h d ( z ). (In this work x stands for the Bjorken scaling variable, and z for the fraction of the quark momentum that is transferred to the pro duced hadron.) Mult...
Mass and charge identification of fragments detected with the Chimera Silicon-CsI(Tl) telescopes
Energy Technology Data Exchange (ETDEWEB)
Le Neindre, N.; Alderighi, M.; Anzalone, A.; Barna, R.; Bartolucci, M.; Berceanu, I.; Borderie, B.; Bougault, R.; Bruno, M.; Cardella, G.; Cavallaro, S.; D' Agostino, M. E-mail: dagostino@bo.infn.it; Dayras, R.; De Filippo, E.; De Pasquale, D.; Geraci, E.; Giustolisi, F.; Grzeszczuk, A.; Guazzoni, P.; Guinet, D.; Iacono-Manno, M.; Italiano, A.; Kowalski, S.; Lanchais, A.; Lanzano, G.; Lanzalone, G.; Li, S.; Lo Nigro, S.; Maiolino, C.; Manfredi, G.; Moisa, D.; Pagano, A.; Papa, M.; Paduszynski, T.; Petrovici, M.; Piasecki, E.; Pirrone, S.; Politi, G.; Pop, A.; Porto, F.; Rivet, M.F.; Rosato, E.; Russo, S.; Sambataro, S.; Sechi, G.; Simion, V.; Sperduto, M.L.; Steckmeyer, J.C.; Sutera, C.; Trifiro, A.; Tassan-Got, L.; Trimarchi, M.; Vannini, G.; Vigilante, M.; Wilczynski, J.; Wu, H.; Xiao, Z.; Zetta, L.; Zipper, W
2002-09-01
Mass and charge identification of charged products detected with Silicon-CsI(Tl) telescopes of the Chimera apparatus are presented. An identification function, based on the Bethe-Bloch formula, is used to fit empirical correlations between {delta}E and E ADC readings, in order to determine, event by event, the atomic and mass numbers of the detected charged reaction products prior to energy calibration.
Influence of joint direction and position of explosive charge on fragmentation
International Nuclear Information System (INIS)
Hafsaoui, Abdellah; Talhi, Korichi
2009-01-01
Although researchers have realized varying degrees of success in small-scale physical in situ testing, most will agree that the greatest uncertainty stems from the uncontrollable field variables. Given the diverse nature of field conditions encountered, there exists no reliable and proven method of predicting fragmentation. Due to the lack of adequate field controls, it is unlikely that a universal physical model will ever be developed for all blasting. This paper presents the results of a test conducted at the Hadjar Essoud quarry to investigate the problems associated with the discontinuities in the rock, which are among the factors causing the reduction of the resistance of the rocks to the explosive. Nevertheless, the distance between the joints, their dip and strike, and the position of the detonator play a significant role in the final fragmentation of the rock. In this work, we studied the role of the abovementioned factors on models of limestone rock of 150 X 375 X 450 mm. Accurate measurement of blast, fragmentation is important in mining and quarrying operations, in monitoring blasts, and optimizing their design. We shall use the Kuznetsov-Rammler method to measure fragmentation. It shows great potential as a practical aid to predict and control the quality of the fragmented material in the Hadjar Essoud quarry. (author)
International Nuclear Information System (INIS)
Saxon, D.H.
1985-10-01
The paper reviews studies on jet fragmentation. The subject is discussed under the topic headings: fragmentation models, charged particle multiplicity, bose-einstein correlations, identified hadrons in jets, heavy quark fragmentation, baryon production, gluon and quark jets compared, the string effect, and two successful models. (U.K.)
2017-05-22
connecting the three quarks. Composite particles composed of partons are known as “hadrons” and must have a neutral color charge. There are six... neutral charge of neutrons. The up quark has positive charge equivalent to two-thirds the charge of an electron, and the down quark has negative...known as “heavy ions.” An ion is an atom or molecule with net electric charge, bare nuclei have a large positive charge due to the absence of
Charge distributions of fission fragments of low- and high-energy fission of Fm, No, and Rf isotopes
Paşca, H.; Andreev, A. V.; Adamian, G. G.; Antonenko, N. V.
2018-03-01
The charge (mass) distributions of fission fragments resulting from low- and high-energy fission of the even-even nuclei 254 -260 ,264Fm , 258 -264No , and 262 -266Rf are studied with the statistical scission-point model. The calculated results are compared with the available experimental data. In contrast to the experimental data, the calculated mass distribution for 258Fm (s.f.) is strikingly similar to the experimental one for 257Fm (s.f.). The transformation of the shape of charge distribution with increasing isospin and excitation energy occurs gradually and in a similar fashion like that of the mass distribution, but slower. For 254Fm(i.f.), 257Fm(nt h,f), and 260Fm (s.f.), the unexpected difference (symmetric or asymmetric) between the shapes of charge and mass distributions is predicted for the first time. At some critical excitation energy, the saturation of the symmetric component of charge (mass) yields is demonstrated.
Spencer, J.; Gajdos, F.; Blumberger, J.
2016-08-01
We introduce a fragment orbital-based fewest switches surface hopping method, FOB-SH, designed to efficiently simulate charge carrier transport in strongly fluctuating condensed phase systems such as organic semiconductors and biomolecules. The charge carrier wavefunction is expanded and the electronic Hamiltonian constructed in a set of singly occupied molecular orbitals of the molecular sites that mediate the charge transfer. Diagonal elements of the electronic Hamiltonian (site energies) are obtained from a force field, whereas the off-diagonal or electronic coupling matrix elements are obtained using our recently developed analytic overlap method. We derive a general expression for the exact forces on the adiabatic ground and excited electronic state surfaces from the nuclear gradients of the charge localized electronic states. Applications to electron hole transfer in a model ethylene dimer and through a chain of ten model ethylenes validate our implementation and demonstrate its computational efficiency. On the larger system, we calculate the qualitative behaviour of charge mobility with change in temperature T for different regimes of the intermolecular electronic coupling. For small couplings, FOB-SH predicts a crossover from a thermally activated regime at low temperatures to a band-like transport regime at higher temperatures. For higher electronic couplings, the thermally activated regime disappears and the mobility decreases according to a power law. This is interpreted by a gradual loss in probability for resonance between the sites as the temperature increases. The polaron hopping model solved for the same system gives a qualitatively different result and underestimates the mobility decay at higher temperatures. Taken together, the FOB-SH methodology introduced here shows promise for a realistic investigation of charge carrier transport in complex organic, aqueous, and biological systems.
Energy Technology Data Exchange (ETDEWEB)
Spencer, J.; Gajdos, F.; Blumberger, J., E-mail: j.blumberger@ucl.ac.uk [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)
2016-08-14
We introduce a fragment orbital-based fewest switches surface hopping method, FOB-SH, designed to efficiently simulate charge carrier transport in strongly fluctuating condensed phase systems such as organic semiconductors and biomolecules. The charge carrier wavefunction is expanded and the electronic Hamiltonian constructed in a set of singly occupied molecular orbitals of the molecular sites that mediate the charge transfer. Diagonal elements of the electronic Hamiltonian (site energies) are obtained from a force field, whereas the off-diagonal or electronic coupling matrix elements are obtained using our recently developed analytic overlap method. We derive a general expression for the exact forces on the adiabatic ground and excited electronic state surfaces from the nuclear gradients of the charge localized electronic states. Applications to electron hole transfer in a model ethylene dimer and through a chain of ten model ethylenes validate our implementation and demonstrate its computational efficiency. On the larger system, we calculate the qualitative behaviour of charge mobility with change in temperature T for different regimes of the intermolecular electronic coupling. For small couplings, FOB-SH predicts a crossover from a thermally activated regime at low temperatures to a band-like transport regime at higher temperatures. For higher electronic couplings, the thermally activated regime disappears and the mobility decreases according to a power law. This is interpreted by a gradual loss in probability for resonance between the sites as the temperature increases. The polaron hopping model solved for the same system gives a qualitatively different result and underestimates the mobility decay at higher temperatures. Taken together, the FOB-SH methodology introduced here shows promise for a realistic investigation of charge carrier transport in complex organic, aqueous, and biological systems.
International Nuclear Information System (INIS)
Volkov, N.G.; Emel'yanov, V.M.; Krajnov, V.P.
1979-01-01
In a statistical fission model calculated are charge distributions of fission fragments (CDFF) of a 236 U* nucleus and their dispersions as the functions of excitation energy and angular momentum (AM) of a compound nucleus as well as the effect of one-particle potential parameter on CDFF. The potential of two-center oscillator was choosen as the one-particle potential. The function of fissioning nucleus level density, which is necessary for calculations in the statistical approach, has been determined from one-particle spectrum. The scheme of calculations is realized with a computer. Presented are the results of calculating the dependence of a neutron gap size on nuclear temperature for various projections of total AM; CDFF for different values of E* excitation energy of AM projection and others. Calculated CDFF and experimental data were compared. Notwithstanding the availability of many parameters and a large volume of numerical calculations the model under consideration permits to describe many common regularities of heavy nucleus CDFF (experimental yields of charges, dispersion dependence on excitation energies and masses of nuclear fragments)
Regnier, D.; Dubray, N.; Schunck, N.; Verrière, M.
2016-05-01
Background: Accurate knowledge of fission fragment yields is an essential ingredient of numerous applications ranging from the formation of elements in the r process to fuel cycle optimization for nuclear energy. The need for a predictive theory applicable where no data are available, together with the variety of potential applications, is an incentive to develop a fully microscopic approach to fission dynamics. Purpose: In this work, we calculate the pre-neutron emission charge and mass distributions of the fission fragments formed in the neutron-induced fission of 239Pu using a microscopic method based on nuclear density functional theory (DFT). Methods: Our theoretical framework is the nuclear energy density functional (EDF) method, where large-amplitude collective motion is treated adiabatically by using the time-dependent generator coordinate method (TDGCM) under the Gaussian overlap approximation (GOA). In practice, the TDGCM is implemented in two steps. First, a series of constrained EDF calculations map the configuration and potential-energy landscape of the fissioning system for a small set of collective variables (in this work, the axial quadrupole and octupole moments of the nucleus). Then, nuclear dynamics is modeled by propagating a collective wave packet on the potential-energy surface. Fission fragment distributions are extracted from the flux of the collective wave packet through the scission line. Results: We find that the main characteristics of the fission charge and mass distributions can be well reproduced by existing energy functionals even in two-dimensional collective spaces. Theory and experiment agree typically within two mass units for the position of the asymmetric peak. As expected, calculations are sensitive to the structure of the initial state and the prescription for the collective inertia. We emphasize that results are also sensitive to the continuity of the collective landscape near scission. Conclusions: Our analysis confirms
Energy Technology Data Exchange (ETDEWEB)
Deng, Banglin, E-mail: banglindeng@yahoo.cn [Department of Applied Physics, Chengdu University of Technology, Chengdu 610059, Sichuan (China); Jiang, Gang [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, Sichuan (China); Zhang, Chuanyu [Department of Applied Physics, Chengdu University of Technology, Chengdu 610059, Sichuan (China)
2014-09-15
In this work, the multi-configuration Dirac–Fock and relativistic configuration-interaction methods have been used to calculate the transition wavelengths, electric dipole transition probabilities, line strengths, and absorption oscillator strengths for the 2s–3p, 2p–3s, and 2p–3d transitions in Li-like ions with nuclear charge Z=7–30. Our calculated values are in good agreement with previous experimental and theoretical results. We took the contributions from Breit interaction, finite nuclear mass corrections, and quantum electrodynamics corrections to the initial and final levels into account, and also found that the contributions from Breit interaction, self-energy, and vacuum polarization grow fast with increasing nuclear charge for a fixed configuration. The ratio of the velocity to length form of the transition rate (A{sub v}/A{sub l}) was used to estimate the accuracy of our calculations.
International Nuclear Information System (INIS)
Facina, M.; Bachelet, C.; Block, M.; Bollen, G.; Davies, D.; Folden, C.M.; Guenaut, C.; Huikari, J.; Kwan, E.; Morrissey, D.J.; Pang, G.K.; Prinke, A.; Ringle, R.; Savory, J.; Schury, P.; Schwarz, S.; Sumithrarachchi, C.; Sun, T.
2008-01-01
The NSCL gas-stopping station thermalizes high-energy projectile fragments for study in the low energy beam and ion trap (LEBIT) facility. The stopping and extraction of fast beams has been studied extensively and the extracted short-lived ions have been used in a series of mass measurements of exotic nuclei. Particle-in-cell simulations of ion drift in the gas cell have been performed. In the present paper calculation results are presented and compared to experimental data obtained with neutron-deficient and neutron-rich As and Se isotopes recently measured at LEBIT. Good agreement between the theoretical and experimental extraction efficiency was found.
Beam analysis spectrometer for relativistic heavy ions
International Nuclear Information System (INIS)
Schimmerling, W.; Subramanian, T.S.; McDonald, W.J.; Kaplan, S.N.; Sadoff, A.; Gabor, G.
1983-01-01
A versatile spectrometer useful for measuring the mass, charge, energy, fluence and angular distribution of primaries and fragments associated with relativistic heavy ion beams is described. The apparatus is designed to provide accurate physical data for biology experiments and medical therapy planning as a function of depth in tissue. The spectrometer can also be used to measure W, the average energy to produce an ion pair, range-energy, dE/dx, and removal cross section data of interest in nuclear physics. (orig.)
International Nuclear Information System (INIS)
Nahrgang, Marlene; Schuster, Tim; Stock, Reinhard; Mitrovski, Michael; Bleicher, Marcus
2012-01-01
We explore the potential of net-baryon, net-proton and net-charge kurtosis measurements to investigate the properties of hot and dense matter created in relativistic heavy-ion collisions. Contrary to calculations in a grand-canonical ensemble we explicitly take into account exact electric and baryon charge conservation on an event-by-event basis. This drastically limits the width of baryon fluctuations. A simple model to account for this is to assume a grand-canonical distribution with a sharp cut-off at the tails. We present baseline predictions of the energy dependence of the net-baryon, net-proton and net-charge kurtosis for central (b≤2.75 fm) Pb+Pb/Au+Au collisions from E lab =2A GeV to √(s NN )=200 GeV from the UrQMD model. While the net-charge kurtosis is compatible with values around zero, the net-baryon number decreases to large negative values with decreasing beam energy. The net-proton kurtosis becomes only slightly negative for low √(s NN ). (orig.)
Experiments with stored relativistic exotic nuclei
International Nuclear Information System (INIS)
Klepper, O.; Attallah, F.; Beckert, K.; Bosch, F.; Dolinskiy, A.; Eickhoff, H.; Franczak, B.; Franzke, B.; Geissel, H.; Hausmann, M.; Hellstroem, M.; Herfurth, F.; Kluge, H.-J.; Kozhuharov, C.; Muenzenberg, G.; Nolden, F.; Quint, W.; Tradon, T.; Reich, H.; Scheidenberger, C.; Schlitt, B.; Steck, M.; Suemmerer, K.; Vermeeren, L.; Winkler, M.; Winkler, Th.; Falch, M.; Kerscher, Th.; Loebner, K.E.G.; Fujita, Y.; Novikov, Yu.; Patyk, Z.; Stadlmann, J.; Wollnik, H.
1999-01-01
Beams of relativistic exotic nuclei were produced, separated and investigated with the combination of the fragment separator FRS and the storage ring ESR. The following experiments are presented: 1) Direct mass measurements of relativistic nickel and bismuth projectile fragments were performed using Schottky spectrometry. Applying electron cooling, the relative velocity spread of the circulating secondary nuclear beams of low intensity was reduced to below 10 -6 . The achieved mass resolving power of m/Δm = 6.5·10 5 (FWHM) in recent measurements represents an improvement by a factor of two compared to authors' previous experiments. The previously unknown masses of more than 100 proton-rich isotopes have been measured in the range of 54≤Z≤84. The results are compared with mass models and estimated values based on extrapolations of experimental values. 2) Exotic nuclei with half-lives shorter than the time required for electron cooling can be investigated by time-of-flight measurements with the ESR being operated in the isochronous mode. This novel experimental technique has been successfully applied in a first measurement with nickel fragments. A mass resolving power of m/Δm = 1.5·10 5 (FWHM) was achieved in this mode of operation. 3) Nuclear half-lives of stored and cooled bare projectile fragments have been measured to study the influence of the ionic charge state on the beta-decay probability
International Nuclear Information System (INIS)
Lynch, J.T.
1999-01-01
Using a lowest-order approximation, the field equations of a general relativistic spinor-connection theory are solved semi-analytically for the fields of a stable, spin-half changed particle near the spin axis. With the exception of the atomic fine-structure constant, all parameters arising in the solution, including the rest mass of the source particle, are found by imposing the standard junction conditions of general relativity and electromagnetism. Using the empirical value for the fine-structure constant, the value derived for the rest mass gives some reason to identify the source particle with the electron. Moreover, since the rest mass is independent of the sign of the electron charge carried by the source, the solution is equally applicable to the positron
Relativistic magnetohydrodynamics
Energy Technology Data Exchange (ETDEWEB)
Hernandez, Juan; Kovtun, Pavel [Department of Physics and Astronomy, University of Victoria,Victoria, BC, V8P 5C2 (Canada)
2017-05-02
We present the equations of relativistic hydrodynamics coupled to dynamical electromagnetic fields, including the effects of polarization, electric fields, and the derivative expansion. We enumerate the transport coefficients at leading order in derivatives, including electrical conductivities, viscosities, and thermodynamic coefficients. We find the constraints on transport coefficients due to the positivity of entropy production, and derive the corresponding Kubo formulas. For the neutral state in a magnetic field, small fluctuations include Alfvén waves, magnetosonic waves, and the dissipative modes. For the state with a non-zero dynamical charge density in a magnetic field, plasma oscillations gap out all propagating modes, except for Alfvén-like waves with a quadratic dispersion relation. We relate the transport coefficients in the “conventional” magnetohydrodynamics (formulated using Maxwell’s equations in matter) to those in the “dual” version of magnetohydrodynamics (formulated using the conserved magnetic flux).
SOFIA: An innovative setup to measure complete isotopic yield of fission fragments
Directory of Open Access Journals (Sweden)
Pellereau E.
2013-12-01
Full Text Available We performed an experiment dedicated to the accurate isotopic yield measurement of fission fragments over the whole range. SOFIA exploits the inverse kinematics technique: using heavy ion beams at relativistic energies, fission is induced by Coulomb excitation in a high-Z target. The fragments are emitted forward and both of them are identified in charge and mass. The setup will be presented, as well as preliminary spectra.
International Nuclear Information System (INIS)
Deibele, C.E.
1996-01-01
The beam impedance and wakefield are quantities which describe the stability of charged particles in their trajectory within an accelerator. The stretched wire measurement technique is a method which estimates the beam impedance and wakefield. Definitions for the beam impedance, the wakefield, and the stretched wire measurement are presented. A pillbox resonator with circular beampipes is studied for its relatively simple profile and mode structure. Theoretical predictions and measurement data are presented for the interaction of various charged particle beams and center conductor geometries between the cavity and beampipe. Time domain predictions for the stretched wire measurement and wakefield are presented and are shown to be a linear interaction
International Nuclear Information System (INIS)
Gross, F.
1986-01-01
Relativistic equations for two and three body scattering are discussed. Particular attention is paid to relativistic three body kinetics because of recent form factor measurements of the Helium 3 - Hydrogen 3 system recently completed at Saclay and Bates and the accompanying speculation that relativistic effects are important for understanding the three nucleon system. 16 refs., 4 figs
International Nuclear Information System (INIS)
Stringfield, R.M.; Fazio, M.V.; Rickel, D.G.; Kwan, T.J.T.; Peratt, A.L.; Kinross-Wright, J.; Van Haaften, F.W.; Hoeberling, R.F.; Faehl, R.; Carlsten, B.; Destler, W.W.; Warner, L.B.
1991-01-01
Los Alamos is investigating a number of high power microwave (HPM) sources for their potential to power advanced accelerators. Included in this investigation are the large orbit gyrotron amplifier and oscillator (LOG) and the relativistic klystron amplifier (RKA). LOG amplifier development is newly underway. Electron beam power levels of 3 GW, 70 ns duration, are planned, with anticipated conversion efficiencies into RF on the order of 20 percent. Ongoing investigations on this device include experimental improvement of the electron beam optics (to allow injection of a suitable fraction of the electron beam born in the gun into the amplifier structure), and computational studies of resonator design and RF extraction. Recent RKA studies have operated at electron beam powers into the device of 1.35 GW in microsecond duration pulses. The device has yielded modulated electron beam power approaching 300 MW using 3-5 kW of RF input drive. RF powers extracted into waveguide have been up to 70 MW, suggesting that more power is available from the device than has been converted to-date in the extractor
Schippers, Stefan
2008-01-01
Dielectronic recombination (DR) of few-electron ions has evolved into a sensitive spectroscopic tool for highly charged ions. This is due to technological advances in electron-beam preparation and ion-beam cooling techniques at heavy-ion storage rings. Recent experiments prove unambiguously that DR collision spectroscopy has become sensitive to 2nd order QED and to nuclear effects. This review discusses the most recent developments in high-resolution spectroscopy of low-energy DR resonances, ...
International Nuclear Information System (INIS)
Denschlag, H.O.; Braun, H.; Wolfsberg, K.
1979-01-01
The fission product yields of the members of the decay chains 132 to 137, 99, and 102 in 235 U(n/sub th/,f) were measured at various kinetic energies and ionic charge states of the fragments using the mass separator for unslowed fission products LOHENGRIN. The results are discussed with respect to four aspects: A preferential formation of neutron rich chain members found at high kinetic energy of the fragments is predominantly due to decreasing prompt neutron evaporation. A particularly large effect in chain 132 is attributed to the double shell closure in Sn-132. The persistence of an even-odd pairing effect in the yields throughout the range of kinetic energies studied leads to the conclusion that the high internal excitation energy of the fragments is tied up mainly in the form of collective energy (e.g., deformation energy) rather than single particle excitation. Generally, the yield distribution at constant kinetic energy is invariant with respect to the ionic charge state of the isotopes separated. Deviations from this behavior found in chains 99, 102, 133, and 136 are interpreted as being due to Auger events following a converted transition in the decay of ns-isomers taking place in the vacuum of the separator. A pronounced variation of the independent formation ratio of single isomeric states with the kinetic energy of the fragments is providing direct information on the controversial topic of the change of angular momentum of fission fragments as a function of deformation (scission distance). 34 references
Chen, Guangye; Luis, Chacon; Bird, Robert; Stark, David; Yin, Lin; Albright, Brian
2017-10-01
Leap-frog based explicit algorithms, either ``energy-conserving'' or ``momentum-conserving'', do not conserve energy discretely. Time-centered fully implicit algorithms can conserve discrete energy exactly, but introduce large dispersion errors in the light-wave modes, regardless of timestep sizes. This can lead to intolerable simulation errors where highly accurate light propagation is needed (e.g. laser-plasma interactions, LPI). In this study, we selectively combine the leap-frog and Crank-Nicolson methods to produce a low-dispersion, exactly energy-and-charge-conserving PIC algorithm. Specifically, we employ the leap-frog method for Maxwell equations, and the Crank-Nicolson method for particle equations. Such an algorithm admits exact global energy conservation, exact local charge conservation, and preserves the dispersion properties of the leap-frog method for the light wave. The algorithm has been implemented in a code named iVPIC, based on the VPIC code developed at LANL. We will present numerical results that demonstrate the properties of the scheme with sample test problems (e.g. Weibel instability run for 107 timesteps, and LPI applications.
Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Bouchet, J.; Brandin, A. V.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Campbell, J. M.; Cebra, D.; Cervantes, M. C.; Chakaberia, I.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, J. H.; Chen, H. F.; Cheng, J.; Cherney, M.; Christie, W.; Codrington, M. J. M.; Contin, G.; Crawford, H. J.; Cui, X.; Das, S.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; Derradi de Souza, R.; di Ruzza, B.; Didenko, L.; Dilks, C.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Eppley, G.; Esha, R.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Federic, P.; Fedorisin, J.; Feng, Filip, P.; Fisyak, Y.; Flores, C. E.; Gagliardi, C. A.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Hamad, A.; Hamed, A.; Han, L.-X.; Haque, R.; Harris, J. W.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, X.; Huang, H. Z.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Kosarzewski, L. K.; Kotchenda, L.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Li, Z. M.; Li, X.; Li, W.; Li, Y.; Li, X.; Li, C.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, R. M.; Ma, Y. G.; Magdy, N.; Mahapatra, D. P.; Majka, R.; Manion, A.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Okorokov, V.; Olvitt, D. L.; Page, B. S.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Poniatowska, K.; Porter, J.; Poskanzer, A. M.; Pruthi, N. K.; Przybycien, M.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandacz, A.; Sandweiss, J.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Simko, M.; Skoby, M. J.; Smirnov, N.; Smirnov, D.; Solanki, D.; Song, L.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Summa, B. J.; Sun, X. M.; Sun, Z.; Sun, Y.; Sun, X.; Surrow, B.; Svirida, D. N.; Szelezniak, M. A.; Takahashi, J.; Tang, Z.; Tang, A. H.; Tarnowsky, T.; Tawfik, A. N.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Tripathy, S. K.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Upsal, I.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wang, J. S.; Wang, X. L.; Wang, Y.; Wang, H.; Wang, F.; Wang, G.; Webb, G.; Webb, J. C.; Wen, L.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, N.; Xu, Z.; Xu, H.; Xu, Y.; Xu, Q. H.; Yan, W.; Yang, Y.; Yang, C.; Yang, Y.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zbroszczyk, H.; Zha, W.; Zhang, X. P.; Zhang, Z. P.; Zhang, J. B.; Zhang, J. L.; Zhang, Y.; Zhang, S.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, Y. H.; Zhu, X.; Zoulkarneeva, Y.; Zyzak, M.; STAR Collaboration
2016-08-01
Balance functions have been measured in terms of relative pseudorapidity (Δ η ) for charged particle pairs at the BNL Relativistic Heavy Ion Collider from Au + Au collisions at √{sNN}=7.7 GeV to 200 GeV using the STAR detector. These results are compared with balance functions measured at the CERN Large Hadron Collider from Pb + Pb collisions at √{sNN}=2.76 TeV by the ALICE Collaboration. The width of the balance function decreases as the collisions become more central and as the beam energy is increased. In contrast, the widths of the balance functions calculated using shuffled events show little dependence on centrality or beam energy and are larger than the observed widths. Balance function widths calculated using events generated by UrQMD are wider than the measured widths in central collisions and show little centrality dependence. The measured widths of the balance functions in central collisions are consistent with the delayed hadronization of a deconfined quark gluon plasma (QGP). The narrowing of the balance function in central collisions at √{sNN}=7.7 GeV implies that a QGP is still being created at this relatively low energy.
Chen, Zhanbin
2018-05-01
The process of excitation of highly charged Fe XXIV ion embedded in weakly coupled plasmas by electron impact is studied, together with the subsequent radiative decay. For the target structure, the calculation is performed using the multiconfiguration Dirac-Hartree-Fock method incorporating the Debye-Hückel potential for the electron-nucleus interaction. Fine-structure levels of the 1s22p and 1s2s2p configurations and the transition properties among these levels are presented over a wide range of screening parameters. For the collision dynamics, the distorted-wave method in the relativistic frame is adopted to include the effect of plasma background, in which the interparticle interactions in the system are described by screened interactions of the Debye-Hückel type. The continuum wave function of the projectile electron is obtained by solving the modified Dirac equations. The influence of plasma strength on the cross section, the linear polarization, and the angular distribution of x-ray photon emission are investigated in detail. Comparison of the present results with experimental data and other theoretical predictions, when available, is made.
Fragment charge and energy distributions in the 1.8-4.8 GeV 3He + natAg, 197Au reactions
International Nuclear Information System (INIS)
Bracken, D.S.; Foxford, E.R.; Kwiatkowski, K.
1995-01-01
Moving source fits have been performed for IMFs as a function of observables related to collision violence in the 1.8-4.8 GeV 3 He + nat Ag, l97 Au reactions. The systematic behavior of the source properties and fragment charge distributions will be reviewed. The evolution of the spectral Coulomb parameters provides evidence for nuclear expansion prior to multifragmentation, suggesting a breakup density of p/p o ∼ 1/3. The charge distributions will be examined in terms of power-law fits and moment analyses
International Nuclear Information System (INIS)
Belovitzky, G.E.; Shteingrad, O.M.
2000-01-01
The mechanism underlying the emission of light charged particles (LCP) with Z = 1, 2 from fragments produced in fission of uranium nuclei by 153 MeV protons and 1700 MeV negative pions was studied. It was found that LCP accompanying the fission by pions are emitted from non-accelerated fragments immediately after the fission, whereas in the case of 153 MeV protons, the LCP are emitted from the accelerated heavy fragments. The number of LCP emitted in the course of pion-induced fission is 0.7 per fission event, which exceeds by a factor of 30 the corresponding number for 153 MeV protons [ru
Energy Technology Data Exchange (ETDEWEB)
Shatskiy, A. A., E-mail: shatskiy@asc.rssi.ru; Novikov, I. D.; Lipatova, L. N. [Russian Academy of Sciences, Astrospace Center, Lebedev Physical Institute (Russian Federation)
2013-06-15
The motion of electric charges and dipoles falling radially and freely into a Schwarzschild black hole is considered. The inverse effect of the electromagnetic fields on the black hole is neglected. Since the dipole is assumed to be a point particle, the deformation due to the action of tidal forces on it is neglected. According to the theorem stating that 'black holes have no hair', the multipole electromagnetic fields should be completely radiated as a multipole falls into a black hole. The electromagnetic radiation power spectrum for these multipoles (a monopole and a dipole) has been found. Differences have been found in the spectra for different orientations of the falling dipole. A general method has been developed to find the radiated multipole electromagnetic fields for multipoles (including higher-order multipoles-quadrupoles, etc.) falling freely into a black hole. The calculated electromagnetic spectra can be compared with observational data from stellar-mass and smaller black holes.
Demianski, Marek
2013-01-01
Relativistic Astrophysics brings together important astronomical discoveries and the significant achievements, as well as the difficulties in the field of relativistic astrophysics. This book is divided into 10 chapters that tackle some aspects of the field, including the gravitational field, stellar equilibrium, black holes, and cosmology. The opening chapters introduce the theories to delineate gravitational field and the elements of relativistic thermodynamics and hydrodynamics. The succeeding chapters deal with the gravitational fields in matter; stellar equilibrium and general relativity
Mechanism of disintegration of sup 2 sup 3 sup 8 U nuclei by relativistic projectiles
Andronenko, L N; Kravtsov, A V; Solyakin, G E
2002-01-01
The sup 2 sup 3 sup 8 U nuclei disintegration through the 16 GeV energy protons and sup 3 He 2 GeV energy nuclei are considered. The pulse mechanism compensation is proposed to explain the formation of collinear mass fragments accompanied by a large amount of charged secondaries and neutrons flying on the m sub 1 relativistic particle heavy nuclei on the account of the particle emission with the mass m sub 2 > m sub 1
International Nuclear Information System (INIS)
Alba, D.; Crater, H.W.; Lusanna, L.
2010-01-01
A complete exposition of the rest-frame instant form of dynamics for arbitrary isolated systems (particles, fields, strings, fluids) admitting a Lagrangian description is given. The starting point is the parametrized Minkowski theory describing the system in arbitrary admissible noninertial frames in Minkowski space-time, which allows one to define the energy-momentum tensor of the system and to show the independence of the description from the clock synchronization convention and from the choice of the 3-coordinates. The restriction to the inertial rest frame, centered on the inertial observer having the Fokker-Pryce center-of-inertia world-line, and the study of relativistic collective variables replacing the nonrelativistic center of mass lead to the description of the isolated system as a decoupled globally defined noncovariant canonical external center of mass carrying a pole-dipole structure (the invariant mass M and the rest spin S¯ of the system) and an external realization of the Poincare group. Mc and S¯ are the energy and angular momentum of a unfaithful internal realization of the Poincare group built with the energy-momentum tensor of the system and acting inside the instantaneous Wigner 3-spaces where all the 3-vectors are Wigner covariant. The vanishing of the internal 3-momentum and of the internal Lorentz boosts eliminate the internal 3-center of mass inside the Wigner 3-spaces, so that at the end the isolated system is described only by Wigner-covariant canonical internal relative variables. Then an isolated system of positive-energy charged scalar articles with mutual Coulomb interaction plus a transverse electromagnetic field in the radiation gauge is investigated as a classical background for defining relativistic atomic physics. The electric charges of the particles are Grassmann-valued to regularize the self-energies. The external and internal realizations of the Poincare algebra in the rest-frame instant form of dynamics are found. This
International Nuclear Information System (INIS)
Sowinski, M.
1975-05-01
The energy distributions and relative intensities of protons, deuterons, tritons and alpha-particles emitted along the fission axis during thermal neutron fission of 236 U are measured simultaneously with the energies of the two fission fragments. The mass distributions of the fragments, the total kinetic energy (TKE), the dependence of the mean TKE on the fragment mass, as well as the mean kinetic energy dependence of polar particles on the fragment mass and energy are deduced from these data. Although some experimental results agree remarkably well with the hypothesis that polar particles are evaporated in-flight from fission fragments, the general conclusion is that these particles are emitted according to some other mechanism
Charge transfer and relativistic effects in the low-lying electronic states of CuCl, CuBr and CuI
Sousa, C; de Jong, W.A.; Broer, R.; Nieuwpoort, WC
1997-01-01
The spectral transitions and the character of the low-lying excited states of the copper halides, CuX (X = Cl, Br, I) are studied by means of two different relativistic computational approaches. One is based on the CASSCF/CASPT2 approach with operators accounting for scalar relativistic effects
Energy Technology Data Exchange (ETDEWEB)
Bandiera, Laura; Bagli, Enrico; Guidi, Vincenzo [INFN Sezione di Ferrara and Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Ferrara, Via Saragat 1, 44121 Ferrara (Italy); Tikhomirov, Victor V. [Research Institute for Nuclear Problems, Belarusian State University, Minsk (Belarus)
2015-07-15
The analytical theories of coherent bremsstrahlung and channeling radiation well describe the process of radiation generation in crystals under some special cases. However, the treatment of complex situations requires the usage of a more general approach. In this report we present a C++ routine, named RADCHARM++, to compute the electromagnetic radiation emitted by electrons and positrons in crystals and complex structures. In the RADCHARM++ routine, the model for the computation of e.m. radiation generation is based on the direct integration of the quasiclassical formula of Baier and Katkov. This approach allows one taking into account real trajectories, and thereby the contribution of incoherent scattering. Such contribution can be very important in many cases, for instance for electron channeling. The generality of the Baier–Katkov operator method permits one to simulate the electromagnetic radiation emitted by electrons/positrons in very different cases, e.g., in straight, bent and periodically bent crystals, and for different beam energy ranges, from sub-GeV to TeV and above. The RADCHARM++ routine has been implemented in the Monte Carlo code DYNECHARM++, which solves the classical equation of motion of charged particles traveling through a crystal under the continuum potential approximation. The code has proved to reproduce the results of experiments performed at the MAinzer MIkrotron (MAMI) with 855 MeV electrons and has been used to predict the radiation spectrum generated by the same electron beam in a bent crystal.
Chatrchyan, Serguei; Sirunyan, Albert M; Tumasyan, Armen; Adam, Wolfgang; Bergauer, Thomas; Dragicevic, Marko; Erö, Janos; Fabjan, Christian; Friedl, Markus; Fruehwirth, Rudolf; Ghete, Vasile Mihai; Hammer, Josef; Hörmann, Natascha; Hrubec, Josef; Jeitler, Manfred; Kiesenhofer, Wolfgang; Knünz, Valentin; Krammer, Manfred; Liko, Dietrich; Mikulec, Ivan; Pernicka, Manfred; Rahbaran, Babak; Rohringer, Christine; Rohringer, Herbert; Schöfbeck, Robert; Strauss, Josef; Taurok, Anton; Wagner, Philipp; Waltenberger, Wolfgang; Walzel, Gerhard; Widl, Edmund; Wulz, Claudia-Elisabeth; Mossolov, Vladimir; Shumeiko, Nikolai; Suarez Gonzalez, Juan; Bansal, Sunil; Cornelis, Tom; De Wolf, Eddi A; Janssen, Xavier; Luyckx, Sten; Maes, Thomas; Mucibello, Luca; Ochesanu, Silvia; Roland, Benoit; Rougny, Romain; Selvaggi, Michele; Staykova, Zlatka; Van Haevermaet, Hans; Van Mechelen, Pierre; Van Remortel, Nick; Van Spilbeeck, Alex; Blekman, Freya; Blyweert, Stijn; D'Hondt, Jorgen; Gonzalez Suarez, Rebeca; Kalogeropoulos, Alexis; Maes, Michael; Olbrechts, Annik; Van Doninck, Walter; Van Mulders, Petra; Van Onsem, Gerrit Patrick; Villella, Ilaria; Charaf, Otman; Clerbaux, Barbara; De Lentdecker, Gilles; Dero, Vincent; Gay, Arnaud; Hreus, Tomas; Léonard, Alexandre; Marage, Pierre Edouard; Reis, Thomas; Thomas, Laurent; Vander Velde, Catherine; Vanlaer, Pascal; Wang, Jian; Adler, Volker; Beernaert, Kelly; Cimmino, Anna; Costantini, Silvia; Garcia, Guillaume; Grunewald, Martin; Klein, Benjamin; Lellouch, Jérémie; Marinov, Andrey; Mccartin, Joseph; Ocampo Rios, Alberto Andres; Ryckbosch, Dirk; Strobbe, Nadja; Thyssen, Filip; Tytgat, Michael; Vanelderen, Lukas; Verwilligen, Piet; Walsh, Sinead; Yazgan, Efe; Zaganidis, Nicolas; Basegmez, Suzan; Bruno, Giacomo; Castello, Roberto; Caudron, Adrien; Ceard, Ludivine; Delaere, Christophe; Du Pree, Tristan; Favart, Denis; Forthomme, Laurent; Giammanco, Andrea; Hollar, Jonathan; Lemaitre, Vincent; Liao, Junhui; Militaru, Otilia; Nuttens, Claude; Pagano, Davide; Perrini, Lucia; Pin, Arnaud; Piotrzkowski, Krzysztof; Schul, Nicolas; Vizan Garcia, Jesus Manuel; Beliy, Nikita; Caebergs, Thierry; Daubie, Evelyne; Hammad, Gregory Habib; Alves, Gilvan; Correa Martins Junior, Marcos; De Jesus Damiao, Dilson; Martins, Thiago; Pol, Maria Elena; Henrique Gomes E Souza, Moacyr; Aldá Júnior, Walter Luiz; Carvalho, Wagner; Custódio, Analu; Melo Da Costa, Eliza; De Oliveira Martins, Carley; Fonseca De Souza, Sandro; Matos Figueiredo, Diego; Mundim, Luiz; Nogima, Helio; Oguri, Vitor; Prado Da Silva, Wanda Lucia; Santoro, Alberto; Soares Jorge, Luana; Sznajder, Andre; Bernardes, Cesar Augusto; De Almeida Dias, Flavia; Tomei, Thiago; De Moraes Gregores, Eduardo; Lagana, Caio; Da Cunha Marinho, Franciole; Mercadante, Pedro G; Novaes, Sergio F; Padula, Sandra; Genchev, Vladimir; Iaydjiev, Plamen; Piperov, Stefan; Rodozov, Mircho; Stoykova, Stefka; Sultanov, Georgi; Tcholakov, Vanio; Trayanov, Rumen; Vutova, Mariana; Dimitrov, Anton; Hadjiiska, Roumyana; Kozhuharov, Venelin; Litov, Leander; Pavlov, Borislav; Petkov, Peicho; Bian, Jian-Guo; Chen, Guo-Ming; Chen, He-Sheng; Jiang, Chun-Hua; Liang, Dong; Liang, Song; Meng, Xiangwei; Tao, Junquan; Wang, Jian; Wang, Xianyou; Wang, Zheng; Xiao, Hong; Xu, Ming; Zang, Jingjing; Zhang, Zhen; Asawatangtrakuldee, Chayanit; Ban, Yong; Guo, Shuang; Guo, Yifei; Li, Wenbo; Liu, Shuai; Mao, Yajun; Qian, Si-Jin; Teng, Haiyun; Wang, Siguang; Zhu, Bo; Zou, Wei; Avila, Carlos; Gomez, Juan Pablo; Gomez Moreno, Bernardo; Osorio Oliveros, Andres Felipe; Sanabria, Juan Carlos; Godinovic, Nikola; Lelas, Damir; Plestina, Roko; Polic, Dunja; Puljak, Ivica; Antunovic, Zeljko; Kovac, Marko; Brigljevic, Vuko; Duric, Senka; Kadija, Kreso; Luetic, Jelena; Morovic, Srecko; Attikis, Alexandros; Galanti, Mario; Mavromanolakis, Georgios; Mousa, Jehad; Nicolaou, Charalambos; Ptochos, Fotios; Razis, Panos A; Finger, Miroslav; Finger Jr, Michael; Assran, Yasser; Elgammal, Sherif; Ellithi Kamel, Ali; Khalil, Shaaban; Mahmoud, Mohammed; Radi, Amr; Kadastik, Mario; Müntel, Mait; Raidal, Martti; Rebane, Liis; Tiko, Andres; Azzolini, Virginia; Eerola, Paula; Fedi, Giacomo; Voutilainen, Mikko; Härkönen, Jaakko; Heikkinen, Mika Aatos; Karimäki, Veikko; Kinnunen, Ritva; Kortelainen, Matti J; Lampén, Tapio; Lassila-Perini, Kati; Lehti, Sami; Lindén, Tomas; Luukka, Panja-Riina; Mäenpää, Teppo; Peltola, Timo; Tuominen, Eija; Tuominiemi, Jorma; Tuovinen, Esa; Ungaro, Donatella; Wendland, Lauri; Banzuzi, Kukka; Korpela, Arja; Tuuva, Tuure; Besancon, Marc; Choudhury, Somnath; Dejardin, Marc; Denegri, Daniel; Fabbro, Bernard; Faure, Jean-Louis; Ferri, Federico; Ganjour, Serguei; Givernaud, Alain; Gras, Philippe; Hamel de Monchenault, Gautier; Jarry, Patrick; Locci, Elizabeth; Malcles, Julie; Millischer, Laurent; Nayak, Aruna; Rander, John; Rosowsky, André; Shreyber, Irina; Titov, Maksym; Baffioni, Stephanie; Beaudette, Florian; Benhabib, Lamia; Bianchini, Lorenzo; Bluj, Michal; Broutin, Clementine; Busson, Philippe; Charlot, Claude; Daci, Nadir; Dahms, Torsten; Dobrzynski, Ludwik; Granier de Cassagnac, Raphael; Haguenauer, Maurice; Miné, Philippe; Mironov, Camelia; Nguyen, Matthew; Ochando, Christophe; Paganini, Pascal; Sabes, David; Salerno, Roberto; Sirois, Yves; Veelken, Christian; Zabi, Alexandre; Agram, Jean-Laurent; Andrea, Jeremy; Bloch, Daniel; Bodin, David; Brom, Jean-Marie; Cardaci, Marco; Chabert, Eric Christian; Collard, Caroline; Conte, Eric; Drouhin, Frédéric; Ferro, Cristina; Fontaine, Jean-Charles; Gelé, Denis; Goerlach, Ulrich; Juillot, Pierre; Karim, Mehdi; Le Bihan, Anne-Catherine; Van Hove, Pierre; Fassi, Farida; Mercier, Damien; Beauceron, Stephanie; Beaupere, Nicolas; Bondu, Olivier; Boudoul, Gaelle; Brun, Hugues; Chasserat, Julien; Chierici, Roberto; Contardo, Didier; Depasse, Pierre; El Mamouni, Houmani; Fay, Jean; Gascon, Susan; Gouzevitch, Maxime; Ille, Bernard; Kurca, Tibor; Lethuillier, Morgan; Mirabito, Laurent; Perries, Stephane; Sordini, Viola; Tosi, Silvano; Tschudi, Yohann; Verdier, Patrice; Viret, Sébastien; Tsamalaidze, Zviad; Anagnostou, Georgios; Beranek, Sarah; Edelhoff, Matthias; Feld, Lutz; Heracleous, Natalie; Hindrichs, Otto; Jussen, Ruediger; Klein, Katja; Merz, Jennifer; Ostapchuk, Andrey; Perieanu, Adrian; Raupach, Frank; Sammet, Jan; Schael, Stefan; Sprenger, Daniel; Weber, Hendrik; Wittmer, Bruno; Zhukov, Valery; Ata, Metin; Caudron, Julien; Dietz-Laursonn, Erik; Duchardt, Deborah; Erdmann, Martin; Fischer, Robert; Güth, Andreas; Hebbeker, Thomas; Heidemann, Carsten; Hoepfner, Kerstin; Klingebiel, Dennis; Kreuzer, Peter; Lingemann, Joschka; Magass, Carsten; Merschmeyer, Markus; Meyer, Arnd; Olschewski, Mark; Papacz, Paul; Pieta, Holger; Reithler, Hans; Schmitz, Stefan Antonius; Sonnenschein, Lars; Steggemann, Jan; Teyssier, Daniel; Weber, Martin; Bontenackels, Michael; Cherepanov, Vladimir; Davids, Martina; Flügge, Günter; Geenen, Heiko; Geisler, Matthias; Haj Ahmad, Wael; Hoehle, Felix; Kargoll, Bastian; Kress, Thomas; Kuessel, Yvonne; Linn, Alexander; Nowack, Andreas; Perchalla, Lars; Pooth, Oliver; Rennefeld, Jörg; Sauerland, Philip; Stahl, Achim; Aldaya Martin, Maria; Behr, Joerg; Behrenhoff, Wolf; Behrens, Ulf; Bergholz, Matthias; Bethani, Agni; Borras, Kerstin; Burgmeier, Armin; Cakir, Altan; Calligaris, Luigi; Campbell, Alan; Castro, Elena; Costanza, Francesco; Dammann, Dirk; Eckerlin, Guenter; Eckstein, Doris; Fischer, David; Flucke, Gero; Geiser, Achim; Glushkov, Ivan; Gunnellini, Paolo; Habib, Shiraz; Hauk, Johannes; Hellwig, Gregor; Jung, Hannes; Kasemann, Matthias; Katsas, Panagiotis; Kleinwort, Claus; Kluge, Hannelies; Knutsson, Albert; Krämer, Mira; Krücker, Dirk; Kuznetsova, Ekaterina; Lange, Wolfgang; Lohmann, Wolfgang; Lutz, Benjamin; Mankel, Rainer; Marfin, Ihar; Marienfeld, Markus; Melzer-Pellmann, Isabell-Alissandra; Meyer, Andreas Bernhard; Mnich, Joachim; Mussgiller, Andreas; Naumann-Emme, Sebastian; Olzem, Jan; Perrey, Hanno; Petrukhin, Alexey; Pitzl, Daniel; Raspereza, Alexei; Ribeiro Cipriano, Pedro M; Riedl, Caroline; Rosin, Michele; Salfeld-Nebgen, Jakob; Schmidt, Ringo; Schoerner-Sadenius, Thomas; Sen, Niladri; Spiridonov, Alexander; Stein, Matthias; Walsh, Roberval; Wissing, Christoph; Autermann, Christian; Blobel, Volker; Bobrovskyi, Sergei; Draeger, Jula; Enderle, Holger; Erfle, Joachim; Gebbert, Ulla; Görner, Martin; Hermanns, Thomas; Höing, Rebekka Sophie; Kaschube, Kolja; Kaussen, Gordon; Kirschenmann, Henning; Klanner, Robert; Lange, Jörn; Mura, Benedikt; Nowak, Friederike; Peiffer, Thomas; Pietsch, Niklas; Rathjens, Denis; Sander, Christian; Schettler, Hannes; Schleper, Peter; Schlieckau, Eike; Schmidt, Alexander; Schröder, Matthias; Schum, Torben; Seidel, Markus; Stadie, Hartmut; Steinbrück, Georg; Thomsen, Jan; Barth, Christian; Berger, Joram; Böser, Christian; Chwalek, Thorsten; De Boer, Wim; Descroix, Alexis; Dierlamm, Alexander; Feindt, Michael; Guthoff, Moritz; Hackstein, Christoph; Hartmann, Frank; Hauth, Thomas; Heinrich, Michael; Held, Hauke; Hoffmann, Karl-Heinz; Honc, Simon; Katkov, Igor; Komaragiri, Jyothsna Rani; Martschei, Daniel; Mueller, Steffen; Müller, Thomas; Niegel, Martin; Nürnberg, Andreas; Oberst, Oliver; Oehler, Andreas; Ott, Jochen; Quast, Gunter; Rabbertz, Klaus; Ratnikov, Fedor; Ratnikova, Natalia; Röcker, Steffen; Scheurer, Armin; Schilling, Frank-Peter; Schott, Gregory; Simonis, Hans-Jürgen; Stober, Fred-Markus Helmut; Troendle, Daniel; Ulrich, Ralf; Wagner-Kuhr, Jeannine; Wayand, Stefan; Weiler, Thomas; Zeise, Manuel; Daskalakis, Georgios; Geralis, Theodoros; Kesisoglou, Stilianos; Kyriakis, Aristotelis; Loukas, Demetrios; Manolakos, Ioannis; Markou, Athanasios; Markou, Christos; Mavrommatis, Charalampos; Ntomari, Eleni; Gouskos, Loukas; Mertzimekis, Theodoros; Panagiotou, Apostolos; Saoulidou, Niki; Evangelou, Ioannis; Foudas, Costas; Kokkas, Panagiotis; Manthos, Nikolaos; Papadopoulos, Ioannis; Patras, Vaios; Bencze, Gyorgy; Hajdu, Csaba; Hidas, Pàl; Horvath, Dezso; Krajczar, Krisztian; Radics, Balint; Sikler, Ferenc; Veszpremi, Viktor; Vesztergombi, Gyorgy; Beni, Noemi; Czellar, Sandor; Molnar, Jozsef; Palinkas, Jozsef; Szillasi, Zoltan; Karancsi, János; Raics, Peter; Trocsanyi, Zoltan Laszlo; Ujvari, Balazs; Beri, Suman Bala; Bhatnagar, Vipin; Dhingra, Nitish; Gupta, Ruchi; Jindal, Monika; Kaur, Manjit; Kohli, Jatinder Mohan; Mehta, Manuk Zubin; Nishu, Nishu; Saini, Lovedeep Kaur; Sharma, Archana; Singh, Jasbir; Ahuja, Sudha; Bhardwaj, Ashutosh; Choudhary, Brajesh C; Kumar, Ashok; Kumar, Arun; Malhotra, Shivali; Naimuddin, Md; Ranjan, Kirti; Sharma, Varun; Shivpuri, Ram Krishen; Banerjee, Sunanda; Bhattacharya, Satyaki; Dutta, Suchandra; Gomber, Bhawna; Jain, Sandhya; Jain, Shilpi; Khurana, Raman; Sarkar, Subir; Sharan, Manoj; Abdulsalam, Abdulla; Choudhury, Rajani Kant; Dutta, Dipanwita; Kailas, Swaminathan; Kumar, Vineet; Mehta, Pourus; Mohanty, Ajit Kumar; Pant, Lalit Mohan; Shukla, Prashant; Aziz, Tariq; Ganguly, Sanmay; Guchait, Monoranjan; Maity, Manas; Majumder, Gobinda; Mazumdar, Kajari; Mohanty, Gagan Bihari; Parida, Bibhuti; Sudhakar, Katta; Wickramage, Nadeesha; Banerjee, Sudeshna; Dugad, Shashikant; Arfaei, Hessamaddin; Bakhshiansohi, Hamed; Etesami, Seyed Mohsen; Fahim, Ali; Hashemi, Majid; Hesari, Hoda; Jafari, Abideh; Khakzad, Mohsen; Mohammadi, Abdollah; Mohammadi Najafabadi, Mojtaba; Paktinat Mehdiabadi, Saeid; Safarzadeh, Batool; Zeinali, Maryam; Abbrescia, Marcello; Barbone, Lucia; Calabria, Cesare; Chhibra, Simranjit Singh; Colaleo, Anna; Creanza, Donato; De Filippis, Nicola; De Palma, Mauro; Fiore, Luigi; Iaselli, Giuseppe; Lusito, Letizia; Maggi, Giorgio; Maggi, Marcello; Marangelli, Bartolomeo; My, Salvatore; Nuzzo, Salvatore; Pacifico, Nicola; Pompili, Alexis; Pugliese, Gabriella; Selvaggi, Giovanna; Silvestris, Lucia; Singh, Gurpreet; Venditti, Rosamaria; Zito, Giuseppe; Abbiendi, Giovanni; Benvenuti, Alberto; Bonacorsi, Daniele; Braibant-Giacomelli, Sylvie; Brigliadori, Luca; Capiluppi, Paolo; Castro, Andrea; Cavallo, Francesca Romana; Cuffiani, Marco; Dallavalle, Gaetano-Marco; Fabbri, Fabrizio; Fanfani, Alessandra; Fasanella, Daniele; Giacomelli, Paolo; Grandi, Claudio; Guiducci, Luigi; Marcellini, Stefano; Masetti, Gianni; Meneghelli, Marco; Montanari, Alessandro; Navarria, Francesco; Odorici, Fabrizio; Perrotta, Andrea; Primavera, Federica; Rossi, Antonio; Rovelli, Tiziano; Siroli, Gianni; Travaglini, Riccardo; Albergo, Sebastiano; Cappello, Gigi; Chiorboli, Massimiliano; Costa, Salvatore; Potenza, Renato; Tricomi, Alessia; Tuve, Cristina; Barbagli, Giuseppe; Ciulli, Vitaliano; Civinini, Carlo; D'Alessandro, Raffaello; Focardi, Ettore; Frosali, Simone; Gallo, Elisabetta; Gonzi, Sandro; Meschini, Marco; Paoletti, Simone; Sguazzoni, Giacomo; Tropiano, Antonio; Benussi, Luigi; Bianco, Stefano; Colafranceschi, Stefano; Fabbri, Franco; Piccolo, Davide; Fabbricatore, Pasquale; Musenich, Riccardo; Benaglia, Andrea; De Guio, Federico; Di Matteo, Leonardo; Fiorendi, Sara; Gennai, Simone; Ghezzi, Alessio; Malvezzi, Sandra; Manzoni, Riccardo Andrea; Martelli, Arabella; Massironi, Andrea; Menasce, Dario; Moroni, Luigi; Paganoni, Marco; Pedrini, Daniele; Ragazzi, Stefano; Redaelli, Nicola; Sala, Silvano; Tabarelli de Fatis, Tommaso; Buontempo, Salvatore; Carrillo Montoya, Camilo Andres; Cavallo, Nicola; De Cosa, Annapaola; Dogangun, Oktay; Fabozzi, Francesco; Iorio, Alberto Orso Maria; Lista, Luca; Meola, Sabino; Merola, Mario; Paolucci, Pierluigi; Azzi, Patrizia; Bacchetta, Nicola; Bellan, Paolo; Bisello, Dario; Branca, Antonio; Carlin, Roberto; Checchia, Paolo; Dorigo, Tommaso; Gasparini, Fabrizio; Gozzelino, Andrea; Kanishchev, Konstantin; Lacaprara, Stefano; Lazzizzera, Ignazio; Margoni, Martino; Meneguzzo, Anna Teresa; Nespolo, Massimo; Pazzini, Jacopo; Perrozzi, Luca; Pozzobon, Nicola; Ronchese, Paolo; Simonetto, Franco; Torassa, Ezio; Tosi, Mia; Vanini, Sara; Zotto, Pierluigi; Zucchetta, Alberto; Zumerle, Gianni; Gabusi, Michele; Ratti, Sergio P; Riccardi, Cristina; Torre, Paola; Vitulo, Paolo; Biasini, Maurizio; Bilei, Gian Mario; Fanò, Livio; Lariccia, Paolo; Lucaroni, Andrea; Mantovani, Giancarlo; Menichelli, Mauro; Nappi, Aniello; Romeo, Francesco; Saha, Anirban; Santocchia, Attilio; Taroni, Silvia; Azzurri, Paolo; Bagliesi, Giuseppe; Boccali, Tommaso; Broccolo, Giuseppe; Castaldi, Rino; D'Agnolo, Raffaele Tito; Dell'Orso, Roberto; Fiori, Francesco; Foà, Lorenzo; Giassi, Alessandro; Kraan, Aafke; Ligabue, Franco; Lomtadze, Teimuraz; Martini, Luca; Messineo, Alberto; Palla, Fabrizio; Rizzi, Andrea; Serban, Alin Titus; Spagnolo, Paolo; Squillacioti, Paola; Tenchini, Roberto; Tonelli, Guido; Venturi, Andrea; Verdini, Piero Giorgio; Barone, Luciano; Cavallari, Francesca; Del Re, Daniele; Diemoz, Marcella; Grassi, Marco; Longo, Egidio; Meridiani, Paolo; Micheli, Francesco; Nourbakhsh, Shervin; Organtini, Giovanni; Paramatti, Riccardo; Rahatlou, Shahram; Sigamani, Michael; Soffi, Livia; Amapane, Nicola; Arcidiacono, Roberta; Argiro, Stefano; Arneodo, Michele; Biino, Cristina; Botta, Cristina; Cartiglia, Nicolo; Costa, Marco; Demaria, Natale; Graziano, Alberto; Mariotti, Chiara; Maselli, Silvia; Migliore, Ernesto; Monaco, Vincenzo; Musich, Marco; Obertino, Maria Margherita; Pastrone, Nadia; Pelliccioni, Mario; Potenza, Alberto; Romero, Alessandra; Ruspa, Marta; Sacchi, Roberto; Sola, Valentina; Solano, Ada; Staiano, Amedeo; Vilela Pereira, Antonio; Belforte, Stefano; Cossutti, Fabio; Della Ricca, Giuseppe; Gobbo, Benigno; Marone, Matteo; Montanino, Damiana; Penzo, Aldo; Schizzi, Andrea; Heo, Seong Gu; Kim, Tae Yeon; Nam, Soon-Kwon; Chang, Sunghyun; Chung, Jin Hyuk; Kim, Dong Hee; Kim, Gui Nyun; Kong, Dae Jung; Park, Hyangkyu; Ro, Sang-Ryul; Son, Dong-Chul; Son, Taejin; Kim, Jae Yool; Kim, Zero Jaeho; Song, Sanghyeon; Jo, Hyun Yong; Choi, Suyong; Gyun, Dooyeon; Hong, Byung-Sik; Jo, Mihee; Kim, Hyunchul; Kim, Tae Jeong; Lee, Kyong Sei; Moon, Dong Ho; Park, Sung Keun; Seo, Eunsung; Choi, Minkyoo; Kang, Seokon; Kim, Hyunyong; Kim, Ji Hyun; Park, Chawon; Park, Inkyu; Park, Sangnam; Ryu, Geonmo; Cho, Yongjin; Choi, Young-Il; Choi, Young Kyu; Goh, Junghwan; Kim, Min Suk; Kwon, Eunhyang; Lee, Byounghoon; Lee, Jongseok; Lee, Sungeun; Seo, Hyunkwan; Yu, Intae; Bilinskas, Mykolas Jurgis; Grigelionis, Ignas; Janulis, Mindaugas; Juodagalvis, Andrius; Castilla-Valdez, Heriberto; De La Cruz-Burelo, Eduard; Heredia-de La Cruz, Ivan; Lopez-Fernandez, Ricardo; Magaña Villalba, Ricardo; Martínez-Ortega, Jorge; Sánchez-Hernández, Alberto; Villasenor-Cendejas, Luis Manuel; Carrillo Moreno, Salvador; Vazquez Valencia, Fabiola; Salazar Ibarguen, Humberto Antonio; Casimiro Linares, Edgar; Morelos Pineda, Antonio; Reyes-Santos, Marco A; Krofcheck, David; Bell, Alan James; Butler, Philip H; Doesburg, Robert; Reucroft, Steve; Silverwood, Hamish; Ahmad, Muhammad; Asghar, Muhammad Irfan; Hoorani, Hafeez R; Khalid, Shoaib; Khan, Wajid Ali; Khurshid, Taimoor; Qazi, Shamona; Shah, Mehar Ali; Shoaib, Muhammad; Brona, Grzegorz; Bunkowski, Karol; Cwiok, Mikolaj; Dominik, Wojciech; Doroba, Krzysztof; Kalinowski, Artur; Konecki, Marcin; Krolikowski, Jan; Bialkowska, Helena; Boimska, Bozena; Frueboes, Tomasz; Gokieli, Ryszard; Górski, Maciej; Kazana, Malgorzata; Nawrocki, Krzysztof; Romanowska-Rybinska, Katarzyna; Szleper, Michal; Wrochna, Grzegorz; Zalewski, Piotr; Almeida, Nuno; Bargassa, Pedrame; David Tinoco Mendes, Andre; Faccioli, Pietro; Fernandes, Miguel; Ferreira Parracho, Pedro Guilherme; Gallinaro, Michele; Seixas, Joao; Varela, Joao; Vischia, Pietro; Afanasiev, Serguei; Belotelov, Ivan; Bunin, Pavel; Gavrilenko, Mikhail; Golutvin, Igor; Gorbunov, Ilya; Karjavin, Vladimir; Kozlov, Guennady; Lanev, Alexander; Malakhov, Alexander; Moisenz, Petr; Palichik, Vladimir; Perelygin, Victor; Shmatov, Sergey; Smirnov, Vitaly; Volodko, Anton; Zarubin, Anatoli; Evstyukhin, Sergey; Golovtsov, Victor; Ivanov, Yury; Kim, Victor; Levchenko, Petr; Murzin, Victor; Oreshkin, Vadim; Smirnov, Igor; Sulimov, Valentin; Uvarov, Lev; Vavilov, Sergey; Vorobyev, Alexey; Vorobyev, Andrey; Andreev, Yuri; Dermenev, Alexander; Gninenko, Sergei; Golubev, Nikolai; Kirsanov, Mikhail; Krasnikov, Nikolai; Matveev, Viktor; Pashenkov, Anatoli; Tlisov, Danila; Toropin, Alexander; Epshteyn, Vladimir; Erofeeva, Maria; Gavrilov, Vladimir; Kossov, Mikhail; Lychkovskaya, Natalia; Popov, Vladimir; Safronov, Grigory; Semenov, Sergey; Stolin, Viatcheslav; Vlasov, Evgueni; Zhokin, Alexander; Belyaev, Andrey; Boos, Edouard; Ershov, Alexander; Gribushin, Andrey; Klyukhin, Vyacheslav; Kodolova, Olga; Korotkikh, Vladimir; Lokhtin, Igor; Markina, Anastasia; Obraztsov, Stepan; Perfilov, Maxim; Petrushanko, Sergey; Popov, Andrey; Sarycheva, Ludmila; Savrin, Viktor; Snigirev, Alexander; Vardanyan, Irina; Andreev, Vladimir; Azarkin, Maksim; Dremin, Igor; Kirakosyan, Martin; Leonidov, Andrey; Mesyats, Gennady; Rusakov, Sergey V; Vinogradov, Alexey; Azhgirey, Igor; Bayshev, Igor; Bitioukov, Sergei; Grishin, Viatcheslav; Kachanov, Vassili; Konstantinov, Dmitri; Korablev, Andrey; Krychkine, Victor; Petrov, Vladimir; Ryutin, Roman; Sobol, Andrei; Tourtchanovitch, Leonid; Troshin, Sergey; Tyurin, Nikolay; Uzunian, Andrey; Volkov, Alexey; Adzic, Petar; Djordjevic, Milos; Ekmedzic, Marko; Krpic, Dragomir; Milosevic, Jovan; Aguilar-Benitez, Manuel; Alcaraz Maestre, Juan; Arce, Pedro; Battilana, Carlo; Calvo, Enrique; Cerrada, Marcos; Chamizo Llatas, Maria; Colino, Nicanor; De La Cruz, Begona; Delgado Peris, Antonio; Diez Pardos, Carmen; Domínguez Vázquez, Daniel; Fernandez Bedoya, Cristina; Fernández Ramos, Juan Pablo; Ferrando, Antonio; Flix, Jose; Fouz, Maria Cruz; Garcia-Abia, Pablo; Gonzalez Lopez, Oscar; Goy Lopez, Silvia; Hernandez, Jose M; Josa, Maria Isabel; Merino, Gonzalo; Puerta Pelayo, Jesus; Quintario Olmeda, Adrián; Redondo, Ignacio; Romero, Luciano; Santaolalla, Javier; Senghi Soares, Mara; Willmott, Carlos; Albajar, Carmen; Codispoti, Giuseppe; de Trocóniz, Jorge F; Cuevas, Javier; Fernandez Menendez, Javier; Folgueras, Santiago; Gonzalez Caballero, Isidro; Lloret Iglesias, Lara; Piedra Gomez, Jonatan; Brochero Cifuentes, Javier Andres; Cabrillo, Iban Jose; Calderon, Alicia; Chuang, Shan-Huei; Duarte Campderros, Jordi; Felcini, Marta; Fernandez, Marcos; Gomez, Gervasio; Gonzalez Sanchez, Javier; Jorda, Clara; Lobelle Pardo, Patricia; Lopez Virto, Amparo; Marco, Jesus; Marco, Rafael; Martinez Rivero, Celso; Matorras, Francisco; Munoz Sanchez, Francisca Javiela; Rodrigo, Teresa; Rodríguez-Marrero, Ana Yaiza; Ruiz-Jimeno, Alberto; Scodellaro, Luca; Sobron Sanudo, Mar; Vila, Ivan; Vilar Cortabitarte, Rocio; Abbaneo, Duccio; Auffray, Etiennette; Auzinger, Georg; Baillon, Paul; Ball, Austin; Barney, David; Bernet, Colin; Bianchi, Giovanni; Bloch, Philippe; Bocci, Andrea; Bonato, Alessio; Breuker, Horst; Camporesi, Tiziano; Cerminara, Gianluca; Christiansen, Tim; Coarasa Perez, Jose Antonio; D'Enterria, David; Dabrowski, Anne; De Roeck, Albert; Di Guida, Salvatore; Dobson, Marc; Dupont-Sagorin, Niels; Elliott-Peisert, Anna; Frisch, Benjamin; Funk, Wolfgang; Georgiou, Georgios; Giffels, Manuel; Gigi, Dominique; Gill, Karl; Giordano, Domenico; Giunta, Marina; Glege, Frank; Gomez-Reino Garrido, Robert; Govoni, Pietro; Gowdy, Stephen; Guida, Roberto; Hansen, Magnus; Harris, Philip; Hartl, Christian; Harvey, John; Hegner, Benedikt; Hinzmann, Andreas; Innocente, Vincenzo; Janot, Patrick; Kaadze, Ketino; Karavakis, Edward; Kousouris, Konstantinos; Lecoq, Paul; Lee, Yen-Jie; Lenzi, Piergiulio; Lourenco, Carlos; Maki, Tuula; Malberti, Martina; Malgeri, Luca; Mannelli, Marcello; Masetti, Lorenzo; Meijers, Frans; Mersi, Stefano; Meschi, Emilio; Moser, Roland; Mozer, Matthias Ulrich; Mulders, Martijn; Musella, Pasquale; Nesvold, Erik; Orimoto, Toyoko; Orsini, Luciano; Palencia Cortezon, Enrique; Perez, Emmanuelle; Petrilli, Achille; Pfeiffer, Andreas; Pierini, Maurizio; Pimiä, Martti; Piparo, Danilo; Polese, Giovanni; Quertenmont, Loic; Racz, Attila; Reece, William; Rodrigues Antunes, Joao; Rolandi, Gigi; Rommerskirchen, Tanja; Rovelli, Chiara; Rovere, Marco; Sakulin, Hannes; Santanastasio, Francesco; Schäfer, Christoph; Schwick, Christoph; Segoni, Ilaria; Sekmen, Sezen; Sharma, Archana; Siegrist, Patrice; Silva, Pedro; Simon, Michal; Sphicas, Paraskevas; Spiga, Daniele; Spiropulu, Maria; Stoye, Markus; Tsirou, Andromachi; Veres, Gabor Istvan; Vlimant, Jean-Roch; Wöhri, Hermine Katharina; Worm, Steven; Zeuner, Wolfram Dietrich; Bertl, Willi; Deiters, Konrad; Erdmann, Wolfram; Gabathuler, Kurt; Horisberger, Roland; Ingram, Quentin; Kaestli, Hans-Christian; König, Stefan; Kotlinski, Danek; Langenegger, Urs; Meier, Frank; Renker, Dieter; Rohe, Tilman; Sibille, Jennifer; Bäni, Lukas; Bortignon, Pierluigi; Buchmann, Marco-Andrea; Casal, Bruno; Chanon, Nicolas; Chen, Zhiling; Deisher, Amanda; Dissertori, Günther; Dittmar, Michael; Dünser, Marc; Eugster, Jürg; Freudenreich, Klaus; Grab, Christoph; Hits, Dmitry; Lecomte, Pierre; Lustermann, Werner; Marini, Andrea Carlo; Martinez Ruiz del Arbol, Pablo; Mohr, Niklas; Moortgat, Filip; Nägeli, Christoph; Nef, Pascal; Nessi-Tedaldi, Francesca; Pandolfi, Francesco; Pape, Luc; Pauss, Felicitas; Peruzzi, Marco; Ronga, Frederic Jean; Rossini, Marco; Sala, Leonardo; Sanchez, Ann - Karin; Starodumov, Andrei; Stieger, Benjamin; Takahashi, Maiko; Tauscher, Ludwig; Thea, Alessandro; Theofilatos, Konstantinos; Treille, Daniel; Urscheler, Christina; Wallny, Rainer; Weber, Hannsjoerg Artur; Wehrli, Lukas; Aguilo, Ernest; Amsler, Claude; Chiochia, Vincenzo; De Visscher, Simon; Favaro, Carlotta; Ivova Rikova, Mirena; Millan Mejias, Barbara; Otiougova, Polina; Robmann, Peter; Snoek, Hella; Tupputi, Salvatore; Verzetti, Mauro; Chang, Yuan-Hann; Chen, Kuan-Hsin; Kuo, Chia-Ming; Li, Syue-Wei; Lin, Willis; Liu, Zong-Kai; Lu, Yun-Ju; Mekterovic, Darko; Singh, Anil; Volpe, Roberta; Yu, Shin-Shan; Bartalini, Paolo; Chang, Paoti; Chang, You-Hao; Chang, Yu-Wei; Chao, Yuan; Chen, Kai-Feng; Dietz, Charles; Grundler, Ulysses; Hou, George Wei-Shu; Hsiung, Yee; Kao, Kai-Yi; Lei, Yeong-Jyi; Lu, Rong-Shyang; Majumder, Devdatta; Petrakou, Eleni; Shi, Xin; Shiu, Jing-Ge; Tzeng, Yeng-Ming; Wan, Xia; Wang, Minzu; Adiguzel, Aytul; Bakirci, Mustafa Numan; Cerci, Salim; Dozen, Candan; Dumanoglu, Isa; Eskut, Eda; Girgis, Semiray; Gokbulut, Gul; Gurpinar, Emine; Hos, Ilknur; Kangal, Evrim Ersin; Karapinar, Guler; Kayis Topaksu, Aysel; Onengut, Gulsen; Ozdemir, Kadri; Ozturk, Sertac; Polatoz, Ayse; Sogut, Kenan; Sunar Cerci, Deniz; Tali, Bayram; Topakli, Huseyin; Vergili, Latife Nukhet; Vergili, Mehmet; Akin, Ilina Vasileva; Aliev, Takhmasib; Bilin, Bugra; Bilmis, Selcuk; Deniz, Muhammed; Gamsizkan, Halil; Guler, Ali Murat; Ocalan, Kadir; Ozpineci, Altug; Serin, Meltem; Sever, Ramazan; Surat, Ugur Emrah; Yalvac, Metin; Yildirim, Eda; Zeyrek, Mehmet; Gülmez, Erhan; Isildak, Bora; Kaya, Mithat; Kaya, Ozlem; Ozkorucuklu, Suat; Sonmez, Nasuf; Cankocak, Kerem; Levchuk, Leonid; Bostock, Francis; Brooke, James John; Clement, Emyr; Cussans, David; Flacher, Henning; Frazier, Robert; Goldstein, Joel; Grimes, Mark; Heath, Greg P; Heath, Helen F; Kreczko, Lukasz; Metson, Simon; Newbold, Dave M; Nirunpong, Kachanon; Poll, Anthony; Senkin, Sergey; Smith, Vincent J; Williams, Thomas; Basso, Lorenzo; Belyaev, Alexander; Brew, Christopher; Brown, Robert M; Cockerill, David JA; Coughlan, John A; Harder, Kristian; Harper, Sam; Jackson, James; Kennedy, Bruce W; Olaiya, Emmanuel; Petyt, David; Radburn-Smith, Benjamin Charles; Shepherd-Themistocleous, Claire; Tomalin, Ian R; Womersley, William John; Bainbridge, Robert; Ball, Gordon; Beuselinck, Raymond; Buchmuller, Oliver; Colling, David; Cripps, Nicholas; Cutajar, Michael; Dauncey, Paul; Davies, Gavin; Della Negra, Michel; Ferguson, William; Fulcher, Jonathan; Futyan, David; Gilbert, Andrew; Guneratne Bryer, Arlo; Hall, Geoffrey; Hatherell, Zoe; Hays, Jonathan; Iles, Gregory; Jarvis, Martyn; Karapostoli, Georgia; Lyons, Louis; Magnan, Anne-Marie; Marrouche, Jad; Mathias, Bryn; Nandi, Robin; Nash, Jordan; Nikitenko, Alexander; Papageorgiou, Anastasios; Pela, Joao; Pesaresi, Mark; Petridis, Konstantinos; Pioppi, Michele; Raymond, David Mark; Rogerson, Samuel; Rose, Andrew; Ryan, Matthew John; Seez, Christopher; Sharp, Peter; Sparrow, Alex; Tapper, Alexander; Vazquez Acosta, Monica; Virdee, Tejinder; Wakefield, Stuart; Wardle, Nicholas; Whyntie, Tom; Chadwick, Matthew; Cole, Joanne; Hobson, Peter R; Khan, Akram; Kyberd, Paul; Leggat, Duncan; Leslie, Dawn; Martin, William; Reid, Ivan; Symonds, Philip; Teodorescu, Liliana; Turner, Mark; Hatakeyama, Kenichi; Liu, Hongxuan; Scarborough, Tara; Henderson, Conor; Rumerio, Paolo; Avetisyan, Aram; Bose, Tulika; Fantasia, Cory; Heister, Arno; St John, Jason; Lawson, Philip; Lazic, Dragoslav; Rohlf, James; Sperka, David; Sulak, Lawrence; Alimena, Juliette; Bhattacharya, Saptaparna; Cutts, David; Ferapontov, Alexey; Heintz, Ulrich; Jabeen, Shabnam; Kukartsev, Gennadiy; Laird, Edward; Landsberg, Greg; Luk, Michael; Narain, Meenakshi; Nguyen, Duong; Segala, Michael; Sinthuprasith, Tutanon; Speer, Thomas; Tsang, Ka Vang; Breedon, Richard; Breto, Guillermo; Calderon De La Barca Sanchez, Manuel; Chauhan, Sushil; Chertok, Maxwell; Conway, John; Conway, Rylan; Cox, Peter Timothy; Dolen, James; Erbacher, Robin; Gardner, Michael; Houtz, Rachel; Ko, Winston; Kopecky, Alexandra; Lander, Richard; Mall, Orpheus; Miceli, Tia; Nelson, Randy; Pellett, Dave; Rutherford, Britney; Searle, Matthew; Smith, John; Squires, Michael; Tripathi, Mani; Vasquez Sierra, Ricardo; Andreev, Valeri; Cline, David; Cousins, Robert; Duris, Joseph; Erhan, Samim; Everaerts, Pieter; Farrell, Chris; Hauser, Jay; Ignatenko, Mikhail; Jarvis, Chad; Plager, Charles; Rakness, Gregory; Schlein, Peter; Tucker, Jordan; Valuev, Vyacheslav; Weber, Matthias; Babb, John; Clare, Robert; Dinardo, Mauro Emanuele; Ellison, John Anthony; Gary, J William; Giordano, Ferdinando; Hanson, Gail; Jeng, Geng-Yuan; Liu, Hongliang; Long, Owen Rosser; Luthra, Arun; Nguyen, Harold; Paramesvaran, Sudarshan; Sturdy, Jared; Sumowidagdo, Suharyo; Wilken, Rachel; Wimpenny, Stephen; Andrews, Warren; Branson, James G; Cerati, Giuseppe Benedetto; Cittolin, Sergio; Evans, David; Golf, Frank; Holzner, André; Kelley, Ryan; Lebourgeois, Matthew; Letts, James; Macneill, Ian; Mangano, Boris; Padhi, Sanjay; Palmer, Christopher; Petrucciani, Giovanni; Pieri, Marco; Sani, Matteo; Sharma, Vivek; Simon, Sean; Sudano, Elizabeth; Tadel, Matevz; Tu, Yanjun; Vartak, Adish; Wasserbaech, Steven; Würthwein, Frank; Yagil, Avraham; Yoo, Jaehyeok; Barge, Derek; Bellan, Riccardo; Campagnari, Claudio; D'Alfonso, Mariarosaria; Danielson, Thomas; Flowers, Kristen; Geffert, Paul; Incandela, Joe; Justus, Christopher; Kalavase, Puneeth; Koay, Sue Ann; Kovalskyi, Dmytro; Krutelyov, Vyacheslav; Lowette, Steven; Mccoll, Nickolas; Pavlunin, Viktor; Rebassoo, Finn; Ribnik, Jacob; Richman, Jeffrey; Rossin, Roberto; Stuart, David; To, Wing; West, Christopher; Apresyan, Artur; Bornheim, Adolf; Chen, Yi; Di Marco, Emanuele; Duarte, Javier; Gataullin, Marat; Ma, Yousi; Mott, Alexander; Newman, Harvey B; Rogan, Christopher; Timciuc, Vladlen; Traczyk, Piotr; Veverka, Jan; Wilkinson, Richard; Yang, Yong; Zhu, Ren-Yuan; Akgun, Bora; Carroll, Ryan; Ferguson, Thomas; Iiyama, Yutaro; Jang, Dong Wook; Liu, Yueh-Feng; Paulini, Manfred; Vogel, Helmut; Vorobiev, Igor; Cumalat, John Perry; Drell, Brian Robert; Edelmaier, Christopher; Ford, William T; Gaz, Alessandro; Heyburn, Bernadette; Luiggi Lopez, Eduardo; Smith, James; Stenson, Kevin; Ulmer, Keith; Wagner, Stephen Robert; Alexander, James; Chatterjee, Avishek; Eggert, Nicholas; Gibbons, Lawrence Kent; Heltsley, Brian; Khukhunaishvili, Aleko; Kreis, Benjamin; Mirman, Nathan; Nicolas Kaufman, Gala; Patterson, Juliet Ritchie; Ryd, Anders; Salvati, Emmanuele; Sun, Werner; Teo, Wee Don; Thom, Julia; Thompson, Joshua; Vaughan, Jennifer; Weng, Yao; Winstrom, Lucas; Wittich, Peter; Winn, Dave; Abdullin, Salavat; Albrow, Michael; Anderson, Jacob; Bauerdick, Lothar AT; Beretvas, Andrew; Berryhill, Jeffrey; Bhat, Pushpalatha C; Bloch, Ingo; Burkett, Kevin; Butler, Joel Nathan; Chetluru, Vasundhara; Cheung, Harry; Chlebana, Frank; Elvira, Victor Daniel; Fisk, Ian; Freeman, Jim; Gao, Yanyan; Green, Dan; Gutsche, Oliver; Hahn, Alan; Hanlon, Jim; Harris, Robert M; Hirschauer, James; Hooberman, Benjamin; Jindariani, Sergo; Johnson, Marvin; Joshi, Umesh; Kilminster, Benjamin; Klima, Boaz; Kunori, Shuichi; Kwan, Simon; Leonidopoulos, Christos; Lincoln, Don; Lipton, Ron; Lueking, Lee; Lykken, Joseph; Maeshima, Kaori; Marraffino, John Michael; Maruyama, Sho; Mason, David; McBride, Patricia; Mishra, Kalanand; Mrenna, Stephen; Musienko, Yuri; Newman-Holmes, Catherine; O'Dell, Vivian; Prokofyev, Oleg; Sexton-Kennedy, Elizabeth; Sharma, Seema; Spalding, William J; Spiegel, Leonard; Tan, Ping; Taylor, Lucas; Tkaczyk, Slawek; Tran, Nhan Viet; Uplegger, Lorenzo; Vaandering, Eric Wayne; Vidal, Richard; Whitmore, Juliana; Wu, Weimin; Yang, Fan; Yumiceva, Francisco; Yun, Jae Chul; Acosta, Darin; Avery, Paul; Bourilkov, Dimitri; Chen, Mingshui; Das, Souvik; De Gruttola, Michele; Di Giovanni, Gian Piero; Dobur, Didar; Drozdetskiy, Alexey; Field, Richard D; Fisher, Matthew; Fu, Yu; Furic, Ivan-Kresimir; Gartner, Joseph; Hugon, Justin; Kim, Bockjoo; Konigsberg, Jacobo; Korytov, Andrey; Kropivnitskaya, Anna; Kypreos, Theodore; Low, Jia Fu; Matchev, Konstantin; Milenovic, Predrag; Mitselmakher, Guenakh; Muniz, Lana; Remington, Ronald; Rinkevicius, Aurelijus; Sellers, Paul; Skhirtladze, Nikoloz; Snowball, Matthew; Yelton, John; Zakaria, Mohammed; Gaultney, Vanessa; Lebolo, Luis Miguel; Linn, Stephan; Markowitz, Pete; Martinez, German; Rodriguez, Jorge Luis; Adams, Jordon Rowe; Adams, Todd; Askew, Andrew; Bochenek, Joseph; Chen, Jie; Diamond, Brendan; Gleyzer, Sergei V; Haas, Jeff; Hagopian, Sharon; Hagopian, Vasken; Jenkins, Merrill; Johnson, Kurtis F; Prosper, Harrison; Veeraraghavan, Venkatesh; Weinberg, Marc; Baarmand, Marc M; Dorney, Brian; Hohlmann, Marcus; Kalakhety, Himali; Vodopiyanov, Igor; Adams, Mark Raymond; Anghel, Ioana Maria; Apanasevich, Leonard; Bai, Yuting; Bazterra, Victor Eduardo; Betts, Russell Richard; Bucinskaite, Inga; Callner, Jeremy; Cavanaugh, Richard; Dragoiu, Cosmin; Evdokimov, Olga; Gauthier, Lucie; Gerber, Cecilia Elena; Hamdan, Saleh; Hofman, David Jonathan; Khalatyan, Samvel; Lacroix, Florent; Malek, Magdalena; O'Brien, Christine; Silkworth, Christopher; Strom, Derek; Varelas, Nikos; Akgun, Ugur; Albayrak, Elif Asli; Bilki, Burak; Clarida, Warren; Duru, Firdevs; Griffiths, Scott; Merlo, Jean-Pierre; Mermerkaya, Hamit; Mestvirishvili, Alexi; Moeller, Anthony; Nachtman, Jane; Newsom, Charles Ray; Norbeck, Edwin; Onel, Yasar; Ozok, Ferhat; Sen, Sercan; Tiras, Emrah; Wetzel, James; Yetkin, Taylan; Yi, Kai; Barnett, Bruce Arnold; Blumenfeld, Barry; Bolognesi, Sara; Fehling, David; Giurgiu, Gavril; Gritsan, Andrei; Guo, Zijin; Hu, Guofan; Maksimovic, Petar; Rappoccio, Salvatore; Swartz, Morris; Whitbeck, Andrew; Baringer, Philip; Bean, Alice; Benelli, Gabriele; Grachov, Oleg; Kenny Iii, Raymond Patrick; Murray, Michael; Noonan, Daniel; Sanders, Stephen; Stringer, Robert; Tinti, Gemma; Wood, Jeffrey Scott; Zhukova, Victoria; Barfuss, Anne-Fleur; Bolton, Tim; Chakaberia, Irakli; Ivanov, Andrew; Khalil, Sadia; Makouski, Mikhail; Maravin, Yurii; Shrestha, Shruti; Svintradze, Irakli; Gronberg, Jeffrey; Lange, David; Wright, Douglas; Baden, Drew; Boutemeur, Madjid; Calvert, Brian; Eno, Sarah Catherine; Gomez, Jaime; Hadley, Nicholas John; Kellogg, Richard G; Kirn, Malina; Kolberg, Ted; Lu, Ying; Marionneau, Matthieu; Mignerey, Alice; Pedro, Kevin; Peterman, Alison; Skuja, Andris; Temple, Jeffrey; Tonjes, Marguerite; Tonwar, Suresh C; Twedt, Elizabeth; Bauer, Gerry; Bendavid, Joshua; Busza, Wit; Butz, Erik; Cali, Ivan Amos; Chan, Matthew; Dutta, Valentina; Gomez Ceballos, Guillelmo; Goncharov, Maxim; Hahn, Kristan Allan; Kim, Yongsun; Klute, Markus; Li, Wei; Luckey, Paul David; Ma, Teng; Nahn, Steve; Paus, Christoph; Ralph, Duncan; Roland, Christof; Roland, Gunther; Rudolph, Matthew; Stephans, George; Stöckli, Fabian; Sumorok, Konstanty; Sung, Kevin; Velicanu, Dragos; Wenger, Edward Allen; Wolf, Roger; Wyslouch, Bolek; Xie, Si; Yang, Mingming; Yilmaz, Yetkin; Yoon, Sungho; Zanetti, Marco; Cooper, Seth; Cushman, Priscilla; Dahmes, Bryan; De Benedetti, Abraham; Franzoni, Giovanni; Gude, Alexander; Haupt, Jason; Kao, Shih-Chuan; Klapoetke, Kevin; Kubota, Yuichi; Mans, Jeremy; Pastika, Nathaniel; Rusack, Roger; Sasseville, Michael; Singovsky, Alexander; Tambe, Norbert; Turkewitz, Jared; Cremaldi, Lucien Marcus; Kroeger, Rob; Perera, Lalith; Rahmat, Rahmat; Sanders, David A; Avdeeva, Ekaterina; Bloom, Kenneth; Bose, Suvadeep; Butt, Jamila; Claes, Daniel R; Dominguez, Aaron; Eads, Michael; Jindal, Pratima; Keller, Jason; Kravchenko, Ilya; Lazo-Flores, Jose; Malbouisson, Helena; Malik, Sudhir; Snow, Gregory R; Baur, Ulrich; Godshalk, Andrew; Iashvili, Ia; Jain, Supriya; Kharchilava, Avto; Kumar, Ashish; Shipkowski, Simon Peter; Smith, Kenneth; Alverson, George; Barberis, Emanuela; Baumgartel, Darin; Chasco, Matthew; Haley, Joseph; Nash, David; Trocino, Daniele; Wood, Darien; Zhang, Jinzhong; Anastassov, Anton; Kubik, Andrew; Mucia, Nicholas; Odell, Nathaniel; Ofierzynski, Radoslaw Adrian; Pollack, Brian; Pozdnyakov, Andrey; Schmitt, Michael Henry; Stoynev, Stoyan; Velasco, Mayda; Won, Steven; Antonelli, Louis; Berry, Douglas; Brinkerhoff, Andrew; Hildreth, Michael; Jessop, Colin; Karmgard, Daniel John; Kolb, Jeff; Lannon, Kevin; Luo, Wuming; Lynch, Sean; Marinelli, Nancy; Morse, David Michael; Pearson, Tessa; Ruchti, Randy; Slaunwhite, Jason; Valls, Nil; Wayne, Mitchell; Wolf, Matthias; Bylsma, Ben; Durkin, Lloyd Stanley; Hart, Andrew; Hill, Christopher; Hughes, Richard; Kotov, Khristian; Ling, Ta-Yung; Puigh, Darren; Rodenburg, Marissa; Vuosalo, Carl; Williams, Grayson; Winer, Brian L; Adam, Nadia; Berry, Edmund; Elmer, Peter; Gerbaudo, Davide; Halyo, Valerie; Hebda, Philip; Hegeman, Jeroen; Hunt, Adam; Lopes Pegna, David; Lujan, Paul; Marlow, Daniel; Medvedeva, Tatiana; Mooney, Michael; Olsen, James; Piroué, Pierre; Quan, Xiaohang; Raval, Amita; Saka, Halil; Stickland, David; Tully, Christopher; Werner, Jeremy Scott; Zuranski, Andrzej; Acosta, Jhon Gabriel; Brownson, Eric; Huang, Xing Tao; Lopez, Angel; Mendez, Hector; Oliveros, Sandra; Ramirez Vargas, Juan Eduardo; Zatserklyaniy, Andriy; Alagoz, Enver; Barnes, Virgil E; Benedetti, Daniele; Bolla, Gino; Bortoletto, Daniela; De Mattia, Marco; Everett, Adam; Hu, Zhen; Jones, Matthew; Koybasi, Ozhan; Kress, Matthew; Laasanen, Alvin T; Leonardo, Nuno; Maroussov, Vassili; Merkel, Petra; Miller, David Harry; Neumeister, Norbert; Shipsey, Ian; Silvers, David; Svyatkovskiy, Alexey; Vidal Marono, Miguel; Yoo, Hwi Dong; Zablocki, Jakub; Zheng, Yu; Guragain, Samir; Parashar, Neeti; Adair, Antony; Boulahouache, Chaouki; Cuplov, Vesna; Ecklund, Karl Matthew; Geurts, Frank JM; Padley, Brian Paul; Redjimi, Radia; Roberts, Jay; Zabel, James; Betchart, Burton; Bodek, Arie; Chung, Yeon Sei; Covarelli, Roberto; de Barbaro, Pawel; Demina, Regina; Eshaq, Yossof; Garcia-Bellido, Aran; Goldenzweig, Pablo; Gotra, Yury; Han, Jiyeon; Harel, Amnon; Korjenevski, Sergey; Miner, Daniel Carl; Vishnevskiy, Dmitry; Zielinski, Marek; Bhatti, Anwar; Ciesielski, Robert; Demortier, Luc; Goulianos, Konstantin; Lungu, Gheorghe; Malik, Sarah; Mesropian, Christina; Arora, Sanjay; Barker, Anthony; Chou, John Paul; Contreras-Campana, Christian; Contreras-Campana, Emmanuel; Duggan, Daniel; Ferencek, Dinko; Gershtein, Yuri; Gray, Richard; Halkiadakis, Eva; Hidas, Dean; Lath, Amitabh; Panwalkar, Shruti; Park, Michael; Patel, Rishi; Rekovic, Vladimir; Richards, Alan; Robles, Jorge; Rose, Keith; Salur, Sevil; Schnetzer, Steve; Seitz, Claudia; Somalwar, Sunil; Stone, Robert; Thomas, Scott; Cerizza, Giordano; Hollingsworth, Matthew; Spanier, Stefan; Yang, Zong-Chang; York, Andrew; Eusebi, Ricardo; Flanagan, Will; Gilmore, Jason; Kamon, Teruki; Khotilovich, Vadim; Montalvo, Roy; Osipenkov, Ilya; Pakhotin, Yuriy; Perloff, Alexx; Roe, Jeffrey; Safonov, Alexei; Sakuma, Tai; Sengupta, Sinjini; Suarez, Indara; Tatarinov, Aysen; Toback, David; Akchurin, Nural; Damgov, Jordan; Dudero, Phillip Russell; Jeong, Chiyoung; Kovitanggoon, Kittikul; Lee, Sung Won; Libeiro, Terence; Roh, Youn; Volobouev, Igor; Appelt, Eric; Engh, Daniel; Florez, Carlos; Greene, Senta; Gurrola, Alfredo; Johns, Willard; Johnston, Cody; Kurt, Pelin; Maguire, Charles; Melo, Andrew; Sheldon, Paul; Snook, Benjamin; Tuo, Shengquan; Velkovska, Julia; Arenton, Michael Wayne; Balazs, Michael; Boutle, Sarah; Cox, Bradley; Francis, Brian; Goodell, Joseph; Hirosky, Robert; Ledovskoy, Alexander; Lin, Chuanzhe; Neu, Christopher; Wood, John; Yohay, Rachel; Gollapinni, Sowjanya; Harr, Robert; Karchin, Paul Edmund; Kottachchi Kankanamge Don, Chamath; Lamichhane, Pramod; Sakharov, Alexandre; Anderson, Michael; Bachtis, Michail; Belknap, Donald; Borrello, Laura; Carlsmith, Duncan; Cepeda, Maria; Dasu, Sridhara; Gray, Lindsey; Grogg, Kira Suzanne; Grothe, Monika; Hall-Wilton, Richard; Herndon, Matthew; Hervé, Alain; Klabbers, Pamela; Klukas, Jeffrey; Lanaro, Armando; Lazaridis, Christos; Leonard, Jessica; Loveless, Richard; Mohapatra, Ajit; Ojalvo, Isabel; Palmonari, Francesco; Pierro, Giuseppe Antonio; Ross, Ian; Savin, Alexander; Smith, Wesley H; Swanson, Joshua
2012-01-01
Jet fragmentation in pp and PbPb collisions at a centre-of-mass energy of 2.76 TeV per nucleon pair was studied using data collected with the CMS detector at the LHC. Fragmentation functions are constructed using charged-particle tracks with transverse momenta pt > 4 GeV for dijet events with a leading jet of pt > 100 GeV. The fragmentation functions in PbPb events are compared to those in pp data as a function of collision centrality, as well as dijet-pt imbalance. Special emphasis is placed on the most central PbPb events including dijets with unbalanced momentum, indicative of energy loss of the hard scattered parent partons. The fragmentation patterns for both the leading and subleading jets in PbPb collisions agree with those seen in pp data at 2.76 TeV. The results provide evidence that, despite the large parton energy loss observed in PbPb collisions, the high-pt component of the fragmentation function evaluated with respect to the reconstructed jet momentum is not strongly modified in comparison to je...
Wang, Bo; Truhlar, Donald G
2013-02-12
Tuned and balanced redistributed charge schemes have been developed for modeling the electrostatic fields of bonds that are cut by a quantum mechanical-molecular mechanical boundary in combined quantum mechanical and molecular mechanical (QM/MM) methods. First, the charge is balanced by adjusting the charge on the MM boundary atom to conserve the total charge of the entire QM/MM system. In the balanced smeared redistributed charge (BSRC) scheme, the adjusted MM boundary charge is smeared with a smearing width of 1.0 Å and is distributed in equal portions to the midpoints of the bonds between the MM boundary atom and the MM atoms bonded to it; in the balanced redistributed charge-2 (BRC2) scheme, the adjusted MM boundary charge is distributed as point charges in equal portions to the MM atoms that are bonded to the MM boundary atom. The QM subsystem is capped by a fluorine atom that is tuned to reproduce the sum of partial atomic charges of the uncapped portion of the QM subsystem. The new aspect of the present study is a new way to carry out the tuning process; in particular, the CM5 charge model, rather than the Mulliken population analysis applied in previous studies, is used for tuning the capping atom that terminates the dangling bond of the QM region. The mean unsigned error (MUE) of the QM/MM deprotonation energy for a 15-system test suite of deprotonation reactions is 2.3 kcal/mol for the tuned BSRC scheme (TBSRC) and 2.4 kcal/mol for the tuned BRC2 scheme (TBRC2). As was the case for the original tuning method based on Mulliken charges, the new tuning method performs much better than using conventional hydrogen link atoms, which have an MUE on this test set of about 7 kcal/mol. However, the new scheme eliminates the need to use small basis sets, which can be problematic, and it allows one to be more consistent by tuning the parameters with whatever basis set is appropriate for applications. (Alternatively, since the tuning parameters and partial charges
Fragmentation of the 56Fe in Al at 1.88A GeV
International Nuclear Information System (INIS)
Bhattacharyya, D.P.; Pal, P.; Basu, B.; Rakshit, R.; Mukherjee, S.C.
1988-01-01
The production of fragmented nuclei from relativistic 56 Fe beam available from LBL Bevalac at 1.88A GeV has been studied using CR-39 (DOP) passive detector placed at an angle of 60 degrees with respect to the beam. The histogram showing the experimental frequency distribution of minor axes of the elliptic etch pit shows the presence of the fragmented nuclei produced with charge number Z from 25 up to 21. The histogram further reveals the presence of nuclei with Z=27 and 28. The production of nuclei heavier than 56 Fe is possibly due to the charge exchange or pick-up phenomena
Zekavat, Behrooz; Miladi, Mahsan; Al-Fdeilat, Abdullah H.; Somogyi, Arpad; Solouki, Touradj
2014-02-01
To date, only a limited number of reports are available on structural variants of multiply-charged b-fragment ions. We report on observed bimodal gas-phase hydrogen/deuterium exchange (HDX) reaction kinetics and patterns for substance P b10 2+ that point to presence of isomeric structures. We also compare HDX reactions, post-ion mobility/collision-induced dissociation (post-IM/CID), and sustained off-resonance irradiation-collision induced dissociation (SORI-CID) of substance P b10 2+ and a cyclic peptide with an identical amino acid (AA) sequence order to substance P b10. The observed HDX patterns and reaction kinetics and SORI-CID pattern for the doubly charged head-to-tail cyclized peptide were different from either of the presumed isomers of substance P b10 2+, suggesting that b10 2+ may not exist exclusively as a head-to-tail cyclized structure. Ultra-high mass measurement accuracy was used to assign identities of the observed SORI-CID fragment ions of substance P b10 2+; over 30 % of the observed SORI-CID fragment ions from substance P b10 2+ had rearranged (scrambled) AA sequences. Moreover, post-IM/CID experiments revealed the presence of two conformer types for substance P b10 2+, whereas only one conformer type was observed for the head-to-tail cyclized peptide. We also show that AA sequence scrambling from CID of doubly-charged b-fragment ions is not unique to substance P b10 2+.
Zekavat, Behrooz; Miladi, Mahsan; Al-Fdeilat, Abdullah H; Somogyi, Arpad; Solouki, Touradj
2014-02-01
To date, only a limited number of reports are available on structural variants of multiply-charged b-fragment ions. We report on observed bimodal gas-phase hydrogen/deuterium exchange (HDX) reaction kinetics and patterns for substance P b10(2+) that point to presence of isomeric structures. We also compare HDX reactions, post-ion mobility/collision-induced dissociation (post-IM/CID), and sustained off-resonance irradiation-collision induced dissociation (SORI-CID) of substance P b10(2+) and a cyclic peptide with an identical amino acid (AA) sequence order to substance P b10. The observed HDX patterns and reaction kinetics and SORI-CID pattern for the doubly charged head-to-tail cyclized peptide were different from either of the presumed isomers of substance P b10(2+), suggesting that b10(2+) may not exist exclusively as a head-to-tail cyclized structure. Ultra-high mass measurement accuracy was used to assign identities of the observed SORI-CID fragment ions of substance P b10(2+); over 30% of the observed SORI-CID fragment ions from substance P b10(2+) had rearranged (scrambled) AA sequences. Moreover, post-IM/CID experiments revealed the presence of two conformer types for substance P b10(2+), whereas only one conformer type was observed for the head-to-tail cyclized peptide. We also show that AA sequence scrambling from CID of doubly-charged b-fragment ions is not unique to substance P b10(2+).
Investigation of prompt gamma-ray yields as a function of mass and charge of 236U fission fragments
International Nuclear Information System (INIS)
Bogdzel', A.A.; Gundorin, N.A.; Duka-Zojomi, A.; Kliman, Ya.; Krishtiak, J.
1987-01-01
New experimental results determining yields of the prompt gamma-rays from the excited states decay of fission fragments are presented. 80 gamma-transitions were observed in 51 fission fragments. The measurements were performed by Ge(Li)-spectrometry in coincidence with fast ionization chamber (10g 235 U). The beam of the resonance neutrons with energy range from 0.7 to 36 eV was used
Fragmentation of Pb-Projectiles at SPS Energies
2002-01-01
% EMU17 \\\\ \\\\ We have exposed stacks consisting of solid state nuclear track detectors (CR-39 plastic and BP-1 glass) and different target materials at the SPS to beams of Pb projectiles. Our detectors record tracks of relativistic nuclei with charge numbers of Z~$\\geq$~6 for CR-39 and Z~$\\geq$75 for BP-1. After development of the tracks by etching they are detected and measured using completely automated microscope systems. Thus experiments with high statistics are possible. \\\\ \\\\BP-1 detectors were exposed to measure total charge changing cross sections and elemental production cross sections for heavy projectile fragments. These experiments were performed for different targets CH$ _{2} $, C, Al, Cu, Ag and Pb. Comparison of the results for different targets allows to investigate contributions to charge changing reactions by electromagnetic dissociation. Multifragmentation events in which several intermediate mass fragments are emitted from the heavy Pb projectile are studied using stacks containing CR-39 d...
Energy Technology Data Exchange (ETDEWEB)
Moeller, Peter [Los Alamos National Laboratory, Theoretical Division, Los Alamos, NM (United States); Schmitt, Christelle [CEA/DSM-CNRS/IN2P3, Grand Accelerateur National d' Ions Lourds, Caen (France)
2017-01-15
We use the Brownian shape-motion model, with its recent extensions, which allow modeling of odd-even staggering, to calculate the evolution of fission-fragment charge distributions with neutron number for the compound-system sequence {sup 234}U, {sup 236}U, {sup 238}U, and {sup 240}U. We compare to experimental data where available, for neutron- and electromagnetic-induced fission over a compound-nucleus excitation energy range from about 6 to 20 MeV. A notable result of the study is that the evolution of the location of the peak charge yield from Z = 54 in {sup 234}U towards Z = 52 in heavier isotopes, seen in the experimental data, is present also in the calculated yields. We further show that to describe yields at higher compound-nucleus excitation energies, then, already at 20 MeV, it is necessary to take multi-chance fission into account. (orig.)
Examining the fragmentation of 158 A GeV lead ions on copper target: Charge-changing cross sections
International Nuclear Information System (INIS)
Rana, Mukhtar Ahmed; Manzoor, Shahid
2008-01-01
A stack of plastic CR-39 Track Detectors were exposed to 158 A GeV 207 Pb ions at the CERN-SPS beam facility. The exposure of stack was performed at normal incidence with a fluence of about 1500ions/cm 2 . The total number of lead ions in each spill was about 7.8x10 4 with eight spills on each stack. For the stack with the Cu target, the lengths of etched cones on one face of the CR-39 detectors (before and after the target) were measured. Using these measurements and charge identification methodology in CR-39 track detectors, total and partial charge changing cross sections of 158 A GeV Pb 82+ ions on Cu and CR-39 targets are determined in the charge region 63≤Z≤82. The possibilities of presence and absence of odd-even effect in measured partial charge changing cross sections of 158 A GeV Pb ions for Cu and CR-39 targets are described. The charge resolution (σ Z ) achieved in the present experiment is ∼0.18e-0.21e. The analysis of discrepancies between our experimental results and other published results for the identical reaction is also presented
Examining the fragmentation of 158 A GeV lead ions on copper target: Charge-changing cross sections
Energy Technology Data Exchange (ETDEWEB)
Rana, Mukhtar Ahmed [Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan)], E-mail: marana@alumni.nus.edu.sg; Manzoor, Shahid [Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan)
2008-09-15
A stack of plastic CR-39 Track Detectors were exposed to 158 A GeV {sup 207}Pb ions at the CERN-SPS beam facility. The exposure of stack was performed at normal incidence with a fluence of about 1500ions/cm{sup 2}. The total number of lead ions in each spill was about 7.8x10{sup 4} with eight spills on each stack. For the stack with the Cu target, the lengths of etched cones on one face of the CR-39 detectors (before and after the target) were measured. Using these measurements and charge identification methodology in CR-39 track detectors, total and partial charge changing cross sections of 158 A GeV Pb{sup 82+} ions on Cu and CR-39 targets are determined in the charge region 63{<=}Z{<=}82. The possibilities of presence and absence of odd-even effect in measured partial charge changing cross sections of 158 A GeV Pb ions for Cu and CR-39 targets are described. The charge resolution ({sigma}{sub Z}) achieved in the present experiment is {approx}0.18e-0.21e. The analysis of discrepancies between our experimental results and other published results for the identical reaction is also presented.
Relativistic impulse dynamics.
Swanson, Stanley M
2011-08-01
Classical electrodynamics has some annoying rough edges. The self-energy of charges is infinite without a cutoff. The calculation of relativistic trajectories is difficult because of retardation and an average radiation reaction term. By reconceptuallizing electrodynamics in terms of exchanges of impulses rather than describing it by forces and potentials, we eliminate these problems. A fully relativistic theory using photonlike null impulses is developed. Numerical calculations for a two-body, one-impulse-in-transit model are discussed. A simple relationship between center-of-mass scattering angle and angular momentum was found. It reproduces the Rutherford cross section at low velocities and agrees with the leading term of relativistic distinguishable-particle quantum cross sections (Møller, Mott) when the distance of closest approach is larger than the Compton wavelength of the particle. Magnetism emerges as a consequence of viewing retarded and advanced interactions from the vantage point of an instantaneous radius vector. Radiation reaction becomes the local conservation of energy-momentum between the radiating particle and the emitted impulse. A net action is defined that could be used in developing quantum dynamics without potentials. A reinterpretation of Newton's laws extends them to relativistic motion.
Analysis of charge-dependent azimuthal correlations with HADES
Energy Technology Data Exchange (ETDEWEB)
Kornas, Frederic [TU Darmstadt (Germany); Selyuzhenkov, Ilya [GSI (Germany); Galatyuk, Tetyana [TU Darmstadt (Germany); GSI (Germany); Collaboration: HADES-Collaboration
2016-07-01
Charge-dependent azimuthal correlations relative to the reaction plane have been proposed as a probe in the search for the chiral magnetic effect in relativistic heavy-ion collisions. These type of correlations have been measured at the RHIC BES by STAR and at the LHC by ALICE. This contribution discusses two charged particle correlations with respect to the reaction plane measured with high statistic sample of Au+Au collisions at 1.23 AGeV collected by HADES. The Forward wall detector allows to reconstruct the reaction plane using the spectator fragments. The status of the analysis with protons and charged pions will be presented.
Rannulu, Nalaka S.; Cole, Richard B.
2012-09-01
The analysis of several bifunctional neutral steroids, 5-α-pregnane diol (5-α-pregnane-3α-20βdiol), estradiol (3,17α-dihydroxy-1,3,5(10)-estratriene), progesterone (4-pregnene-3,20-dione), lupeol (3β-hydroxy-20(29)-lupene), pregnenolone (5-pregnen-3β-ol-20-one), and pregnenolone acetate (5-pregnen-3β-ol-20-one acetate) was accomplished by negative ion electrospray mass spectrometry (ESI-MS) employing adduct formation with various anions: fluoride, bicarbonate, acetate, and chloride. Fluoride yielded higher abundances of anionic adducts and more substantial abundances of deprotonated molecules compared with other investigated anions. Collision-induced dissociation (CID) of precursor [M + anion]- adducts of these steroids revealed that fluoride adduct [M + F]- precursors first lose HF to produce [M - H]- and then undergo consecutive decompositions to yield higher abundances of structurally-informative product ions than the other tested anions. In addition to charge-remote fragmentations, the majority of CID pathways of estradiol are deduced to occur via charge-induced fragmentation. Most interestingly, certain anions exhibit preferential attachment to a specific site on these bifunctional steroid molecules, which we are calling "regioselective anion attachment." Regioselective anion attachment is evidenced by subsequent regiospecific decomposition. Regioselective attachment of fluoride (and acetate) anions to low (and moderate) acidity functional groups of pregnenolone, respectively, is demonstrated using deuterated compounds. Moreover, the formation of unique intermediate ion-dipole complexes leading to novel fragmentation pathways of fluoride adducts of pregnenolone acetate, and bicarbonate adducts of d4-pregnenolone, are also discussed.
Luciano, Rezzolla
2013-01-01
Relativistic hydrodynamics is a very successful theoretical framework to describe the dynamics of matter from scales as small as those of colliding elementary particles, up to the largest scales in the universe. This book provides an up-to-date, lively, and approachable introduction to the mathematical formalism, numerical techniques, and applications of relativistic hydrodynamics. The topic is typically covered either by very formal or by very phenomenological books, but is instead presented here in a form that will be appreciated both by students and researchers in the field. The topics covered in the book are the results of work carried out over the last 40 years, which can be found in rather technical research articles with dissimilar notations and styles. The book is not just a collection of scattered information, but a well-organized description of relativistic hydrodynamics, from the basic principles of statistical kinetic theory, down to the technical aspects of numerical methods devised for the solut...
International Nuclear Information System (INIS)
Balakirev, V.A.; Buts, V.A.
1982-01-01
The interaction of a relativistic electron beam with a plasma waveguide whose density is modulated by an ion acoustic wave leads to the emission of electromagnetic radiation. The wavelength of the radiation is 2#betta# 2 times shorter than the ion acoustic wavelength. The emission is accompanied by the amplification of the ion acoustic wave. The maximum amplitudes of the excited waves are found
Relativistic effects in the Thomas--Fermi atom
International Nuclear Information System (INIS)
Waber, J.T.; Canfield, J.M.
1975-01-01
Two methods of applying relativistic corrections to the Thomas--Fermi atom are considered, and numerical calculations are discussed. Radial charge distributions calculated from a relativistic Thomas--Fermi equation agree in gross form with those from more complicated self-consistent calculations. Energy eigenvalues for mercury, as determined from the relativistic Thomas--Fermi solution, are compared with other calculated and experimental values
Price, R H
1993-01-01
Work reported in the workshop on relativistic astrophysics spanned a wide varicy of topics. Two speciﬁc areas seemed of particular interest. Much attention was focussed on gravitational wave sources, especially on the waveforms they produce, and progress was reported in theoretical and observational aspects of accretion disks.
Sahoo, Raghunath
2016-01-01
This lecture note covers Relativistic Kinematics, which is very useful for the beginners in the field of high-energy physics. A very practical approach has been taken, which answers "why and how" of the kinematics useful for students working in the related areas.
International Nuclear Information System (INIS)
Font, J. A.
2015-01-01
The relativistic astrophysics is the field of astrophysics employing the theory of relativity Einstein as physical-mathematical model is to study the universe. This discipline analyzes astronomical contexts in which the laws of classical mechanics of Newton's law of gravitation are not valid. (Author)
Jiang, Yutao; Hascall, Daniel; Li, Delia; Pease, Joseph H
2015-09-11
In this paper, we introduce a high throughput LCMS/UV/CAD/CLND system that improves upon previously reported systems by increasing both the quantitation accuracy and the range of compounds amenable to testing, in particular, low molecular weight "fragment" compounds. This system consists of a charged aerosol detector (CAD) and chemiluminescent nitrogen detector (CLND) added to a LCMS/UV system. Our results show that the addition of CAD and CLND to LCMS/UV is more reliable for concentration determination for a wider range of compounds than either detector alone. Our setup also allows for the parallel analysis of each sample by all four detectors and so does not significantly increase run time per sample. Copyright © 2015 Elsevier B.V. All rights reserved.
An energy principle for two-dimensional collisionless relativistic plasmas
International Nuclear Information System (INIS)
Otto, A.; Schindler, K.
1984-01-01
Using relativistic Vlasov theory an energy principle for two-dimensional plasmas is derived, which provides a sufficient and necessary criterion for the stability of relativistic plasma equilibria. This energy principle includes charge separating effects since the exact Poisson equation was taken into consideration. Applying the variational principle to the case of the relativistic plane plasma sheet, the same marginal wave length is found as in the non-relativistic case. (author)
Nonlinear dynamics of the relativistic standard map
International Nuclear Information System (INIS)
Nomura, Y.; Ichikawa, Y.H.; Horton, W.
1991-04-01
Heating and acceleration of charged particles by RF fields have been extensively investigated by the standard map. The question arises as to how the relativistic effects change the nonlinear dynamical behavior described by the classical standard map. The relativistic standard map is a two parameter (K, Β = ω/kc) family of dynamical systems reducing to the standard map when Β → 0. For Β ≠ 0 the relativistic mass increase suppresses the onset of stochasticity. It shown that the speed of light limits the rate of advance of the phase in the relativistic standard map and introduces KAM surfaces persisting in the high momentum region. An intricate structure of mixing in the higher order periodic orbits and chaotic orbits is analyzed using the symmetry properties of the relativistic standard map. The interchange of the stability of the periodic orbits in the relativistic standard map is also observed and is explained by the local linear stability of the orbits. 12 refs., 16 figs
International Nuclear Information System (INIS)
Ray, E.M.
1991-06-01
This work is devoted to the experimental study of the interaction between fast (10 to 120 keV/p) hydrogen clusters with thin solid targets. First, we have studied the slowing-down of H n + (2≤n≤21) clusters through carbon foils. Up to date this had been made only with molecular ions. We obtain evidence for vicinage effects on the energy loss of proton-clusters. We show that for projectile energies larger than 50 keV/p, the energy loss of a proton in a cluster is enhanced when compared to that of an isolated proton of the same velocity. At lower incident energies, it is a decrease of the energy loss which is observed. The same effect is also observed in the energy lost in the entrance window of a surface barrier detector bombarded by clusters. This phenomenon is interpreted in terms of interferences between individual polarisation wakes induced by each proton of the cluster. In the second part, we propose an accurate method to study the charge state of the atomic fragments resulting from the dissociation of fast H n + (2≤n≤15) clusters through a carbon foil. This method gives also the distribution of the neutral atoms among the emerging fragments. These distributions are finally compared with binomial laws expected from independent particles
International Nuclear Information System (INIS)
Allen, M.A.; Azuma, O.; Callin, R.S.
1989-03-01
Experimental work is underway by a SLAC-LLNL-LBL collaboration to investigate the feasibility of using relativistic klystrons as a power source for future high gradient accelerators. Two different relativistic klystron configurations have been built and tested to date: a high grain multicavity klystron at 11.4 GHz and a low gain two cavity subharmonic buncher driven at 5.7 GHz. In both configurations power is extracted at 11.4 GHz. In order to understand the basic physics issues involved in extracting RF from a high power beam, we have used both a single resonant cavity and a multi-cell traveling wave structure for energy extraction. We have learned how to overcome our previously reported problem of high power RF pulse shortening, and have achieved peak RF power levels of 170 MW with the RF pulse of the same duration as the beam current pulse. 6 refs., 3 figs., 3 tabs
Relativistic distances, sizes, lengths
International Nuclear Information System (INIS)
Strel'tsov, V.N.
1992-01-01
Such notion as light or retarded distance, field size, formation way, visible size of a body, relativistic or radar length and wave length of light from a moving atom are considered. The relation between these notions is cleared up, their classification is given. It is stressed that the formation way is defined by the field size of a moving particle. In the case of the electromagnetic field, longitudinal sizes increase proportionally γ 2 with growing charge velocity (γ is the Lorentz-factor). 18 refs
Hakim, Rémi
1994-01-01
Il existe à l'heure actuelle un certain nombre de théories relativistes de la gravitation compatibles avec l'expérience et l'observation. Toutefois, la relativité générale d'Einstein fut historiquement la première à fournir des résultats théoriques corrects en accord précis avec les faits.
International Nuclear Information System (INIS)
Marks, R.
1985-09-01
Theoretical analysis is presented of a relativisic klystron; i.e. a high-relativistic bunched electron beam which is sent through a succession of tuned cavities and has its energy replenished by periodic induction accelerator units. Parameters are given for a full-size device and for an experimental device using the FEL at the ETA; namely the ELF Facility. 6 refs., 2 figs
Energy Technology Data Exchange (ETDEWEB)
Rucinski, A; Mancini-Terracciano, C; Paramatti, R; Pinci, D; Russomando, A; Voena, C [Istituto Nazionale di Fisica Nucleare - Sezione di Roma, Rome, Rome (Italy); Battistoni, G; Muraro, S [Istituto Nazionale di Fisica Nucleare - Sezione di Milano, Milano, Milano (Italy); Collamati, F; Faccini, R; Camillocci, E Solfaroli [Istituto Nazionale di Fisica Nucleare - Sezione di Roma, Italy, Dipartiment, Rome, Rome (Italy); Collini, F [Istituto Nazionale di Fisica Nucleare - Sezione di Pisa, Pisa, Pisa (Italy); De Lucia, E; Piersanti, L; Toppi, M [Laboratori Nazionali di Frascati, Frascati (rome), Rome (Italy); Frallicciardi, P [Museo Storico della Fisica e Centro Studi e Ricerche E. Fermi, Rome, Rome (Italy); Marafini, M [Istituto Nazionale di Fisica Nucleare - Sezione di Roma, Museo Storico dell, Rome, Rome (Italy); Patera, V; Sciubba, A; Traini, G [Istituto Nazionale di Fisica Nucleare - Sezione di Roma, Dipartimento di Sc, Rome, Rome (Italy); and others
2016-06-15
Purpose: In Charged Particle Therapy (CPT), besides protons, there has been recently a growing interest in 4He, 12C and 16O beams. The secondary radiation produced in the interaction of those beams with a patient could be potentially used for on-line monitoring of range uncertainties in order to fully exploit the advantages of those light ions resulting from increased Radio Biological Effectiveness, reduced multiple scattering and Oxygen Enhancement Ratio. The study and precise characterization of secondary radiation (beta+, prompt gamma, charged fragments) is the cornerstone of any R&D activity aiming for online monitoring development and purpose of the analysis presented here. Methods: We present the measurements of the secondary radiation generated by He, C and O beams impinging on a beam stopping PMMA target. The data has been collected at the Heidelberg Ionbeam Therapy center (HIT), where several millions of collisions were recorded at different energies, relevant for therapeutical applications. Results: The experimental setup, as well as the analysis strategies will be reviewed. The detected particle fluxes as a function of the primary beam energy and the emission angle with respect to the beam direction will be presented and compared to the results of other available measurements. In addition, the energy spectra and emission shapes of charged secondary particles will be shown and discussed in the context of the primary beam range monitoring technique that is being developed by the ARPG collaboration, within the INSIDE project funded by the Italian research ministry. The implications for dose monitoring applications will be discussed, in the context of the current (or planned) state-of- the-art detector solutions. Conclusion: The characterization of the radiation produced by 12C, 4He and 16O beams fully supports the feasibility of on-line range monitoring in the clinical practice of CPT by means of secondary particles detection.
International Nuclear Information System (INIS)
Rucinski, A; Mancini-Terracciano, C; Paramatti, R; Pinci, D; Russomando, A; Voena, C; Battistoni, G; Muraro, S; Collamati, F; Faccini, R; Camillocci, E Solfaroli; Collini, F; De Lucia, E; Piersanti, L; Toppi, M; Frallicciardi, P; Marafini, M; Patera, V; Sciubba, A; Traini, G
2016-01-01
Purpose: In Charged Particle Therapy (CPT), besides protons, there has been recently a growing interest in 4He, 12C and 16O beams. The secondary radiation produced in the interaction of those beams with a patient could be potentially used for on-line monitoring of range uncertainties in order to fully exploit the advantages of those light ions resulting from increased Radio Biological Effectiveness, reduced multiple scattering and Oxygen Enhancement Ratio. The study and precise characterization of secondary radiation (beta+, prompt gamma, charged fragments) is the cornerstone of any R&D activity aiming for online monitoring development and purpose of the analysis presented here. Methods: We present the measurements of the secondary radiation generated by He, C and O beams impinging on a beam stopping PMMA target. The data has been collected at the Heidelberg Ionbeam Therapy center (HIT), where several millions of collisions were recorded at different energies, relevant for therapeutical applications. Results: The experimental setup, as well as the analysis strategies will be reviewed. The detected particle fluxes as a function of the primary beam energy and the emission angle with respect to the beam direction will be presented and compared to the results of other available measurements. In addition, the energy spectra and emission shapes of charged secondary particles will be shown and discussed in the context of the primary beam range monitoring technique that is being developed by the ARPG collaboration, within the INSIDE project funded by the Italian research ministry. The implications for dose monitoring applications will be discussed, in the context of the current (or planned) state-of- the-art detector solutions. Conclusion: The characterization of the radiation produced by 12C, 4He and 16O beams fully supports the feasibility of on-line range monitoring in the clinical practice of CPT by means of secondary particles detection.
International Nuclear Information System (INIS)
Baranov, I.; Jarmiychuk, S.; Kirillov, S.; Novikov, A.; Obnorskii, V.; Pchelintsev, A.; Wien, K.; Reimann, C.
1999-01-01
In this work the charge state of the negatively charged gold nanocluster ions (2-20 nm) that were desorbed from nanodispersed gold islet targets by 252 Cf fission fragments via electronic processes is studied. Mean cluster charge was calculated as a ratio of mean cluster mass to mean mass-to-charge ratio . Cluster masses were measured by means of a collector technique employing transmission electron microscopy and scanning force microscopy, while m/q was measured by means of a tandem TOF-spectrometer. It is shown that the nanocluster ions are mostly multiply charged (2-16e) and the charge increases non-linearly with the cluster size. The results are discussed
Charge, mass and energy measured in the Plastic Ball
International Nuclear Information System (INIS)
Gustafsson, H.A.; Gutbrod, H.H.; Kolb, B.
1984-01-01
In relativistic nuclear collisions the multiplicity of charged particles reflects the violence of the reaction and, presumably, the impact parameter. Furthermore, the total transverse energy in a collision might be a signature of compression. Both quantities are global features that can be measured in the Plastic Ball. The total mass in an event in light charge fragments can be detected (with assumptions made in certain kinematic regions) through particle identification. In addition, the neutron detection efficiency is quite high because of the large thickness of the plastic scintillator in the Plastic Ball. Here the authors present several global quantities for the reaction of 400 MeV/nucleon Nb + Nb
International Nuclear Information System (INIS)
Luckstead, S.C.
1978-09-01
Differential production cross sections for multiply charged fragments from 800-MeV proton-induced spallation of 12 C, 27 Al, and natural Ni were measured at 30 and 90 degrees. The ion fragments were identified by use of time-of-flight, ΔE--E detector telescope capable of complete particle identification for energies as low as .25 MeV/nucleon. The very short ranges of the particles of interest required the construction of very thin detectors with minimal deadlayer material. The time-pick-off detectors and gas ionization chamber developed are unique, and represent the state-of-the-art in fast timing for time-of-flight measurements and in construction of thin detectors. The resolutions achieved allowed the cross sections of 3 He, 4 He, 6 Li, 7 Li, 7 Be, 9 Be, 10 Be, 10 B, 11 B, 11 C, 12 C, and 13 C to be determined, along with those of nitrogen and oxygen without isotope separation. The cross sections were found to have weak angular dependence. Consequently, pseudo cross sections were calculated from the 90 0 data by integrating the differential cross sections from 0 to 25 MeV for each product and multiplying by 4π. Pseudo theoretical cross sections were similarly calculated from theoretical differential cross sections. These differential cross sections were calculated by use of a Monte Carlo computer code which incorporated the cascade-evaporation model of high-energy nuclear reactions. Implications are drawn for modifications of the model. The results suggest reducing the transparency of the struck nucleus to pions produced in the cascade stage of the reaction model in order that a higher excitation energy be left for the evaporation stage. Also, there is some evidence that evaporations of nuclear aggregates more massive than 4 He occur. Inclusion of such evaporations should improve the model. 82 figures, 1 table
International Nuclear Information System (INIS)
Agarwal, S.; Babinet, R.; Cauvin, B.; Girard, J.; Auger, P.; Chiang, T.; Galin, J.; Gatty, B.; Guerreau, D.; Tarrago, X.
1979-01-01
The light charged particles emitted in coincidence with the main fragments from deep inelastic collisions in the 40 Ar (280 MeV) + 58 Ni have been studied. Both radial (in the reaction plane) and azimuthal angular distributions have been measured. For very asymmetric splitting, the radial angular distribution of the α particles shows two components one of which could be attributed to statistical evaporation by the heavy partner of the detected light fragment. The azimuthal distribution of that component clearly indicates a strong alignment of the spin of the emitting fragment with the orbital angular momentum and a preference for the 'sticking' limit. For symmetric splitting, some α particle energy spectra could not be explained in terms of statistical evaporation by either of the two main fragments. (orig.)
Jovanović, Dušan; Fedele, Renato; De Nicola, Sergio; Akhter, Tamina; Belić, Milivoj
2017-12-01
A self-consistent nonlinear hydrodynamic theory is presented of the propagation of a long and thin relativistic electron beam, for a typical plasma wake field acceleration configuration in an unmagnetized and overdense plasma. The random component of the trajectories of the beam particles as well as of their velocity spread is modelled by an anisotropic temperature, allowing the beam dynamics to be approximated as a 3D adiabatic expansion/compression. It is shown that even in the absence of the nonlinear plasma wake force, the localisation of the beam in the transverse direction can be achieved owing to the nonlinearity associated with the adiabatic compression/rarefaction and a coherent stationary state is constructed. Numerical calculations reveal the possibility of the beam focussing and defocussing, but the lifetime of the beam can be significantly extended by the appropriate adjustments, so that transverse oscillations are observed, similar to those predicted within the thermal wave and Vlasov kinetic models.
Gravitational field of charged gyratons
Energy Technology Data Exchange (ETDEWEB)
Frolov, Valeri P [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta, T6G 2J1 (Canada); Zelnikov, Andrei [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta, T6G 2J1 (Canada); Lebedev Physics Institute, Leninsky prospect 53, 119 991, Moscow (Russian Federation)
2006-03-21
We study relativistic gyratons which carry an electric charge. The Einstein-Maxwell equations in arbitrary dimensions are solved exactly in the case of a charged gyraton propagating in an asymptotically flat metric.
Directory of Open Access Journals (Sweden)
Przemysław Karpowicz
Full Text Available The proteasome is a giant protease responsible for degradation of the majority of cytosolic proteins. Competitive inhibitors of the proteasome are used against aggressive blood cancers. However, broadening the use of proteasome-targeting drugs requires new mechanistic approaches to the enzyme's inhibition. In our previous studies we described Tat1 peptide, an allosteric inhibitor of the proteasome derived from a fragment of the basic domain of HIV-Tat1 protein. Here, we attempted to dissect the structural determinants of the proteasome inhibition by Tat1. Single- and multiple- alanine walking scans were performed. Tat1 analogs with stabilized beta-turn conformation at positions 4-5 and 8-9, pointed out by the molecular dynamics modeling and the alanine scan, were synthesized. Structure of Tat1 analogs were analyzed by circular dichroism, Fourier transform infrared and nuclear magnetic resonance spectroscopy studies, supplemented by molecular dynamics simulations. Biological activity tests and structural studies revealed that high flexibility and exposed positive charge are hallmarks of Tat1 peptide. Interestingly, stabilization of a beta-turn at the 8-9 position was necessary to significantly improve the inhibitory potency.
Zhang, Bing; Li, Kunyang
2018-02-01
The “Breakthrough Starshot” aims at sending near-speed-of-light cameras to nearby stellar systems in the future. Due to the relativistic effects, a transrelativistic camera naturally serves as a spectrograph, a lens, and a wide-field camera. We demonstrate this through a simulation of the optical-band image of the nearby galaxy M51 in the rest frame of the transrelativistic camera. We suggest that observing celestial objects using a transrelativistic camera may allow one to study the astronomical objects in a special way, and to perform unique tests on the principles of special relativity. We outline several examples that suggest transrelativistic cameras may make important contributions to astrophysics and suggest that the Breakthrough Starshot cameras may be launched in any direction to serve as a unique astronomical observatory.
On the physics of relativistic double layers
International Nuclear Information System (INIS)
Carlqvist, P.
1982-06-01
A model of a strong, time-independent, and relativistic double layer is studied. Besides double layers having the electric field parallel to the current the model also describes a certain type of oblique double layers. The 'Langmuir condition' (ratio of ion current density to electron current density) as well as an expression for the potential drop of the double layer are derived. Furthermore, the distribution of charged particles, electric field, and potential within the double layer are clarified and discussed. It is found that the properties of relativistic double layers differ substantially from the properties of corresponding non-relativistic double layers. (Author)
Diffraction radiation from relativistic particles
Potylitsyn, Alexander Petrovich; Strikhanov, Mikhail Nikolaevich; Tishchenko, Alexey Alexandrovich
2010-01-01
This book deals with diffraction radiation, which implies the boundary problems of electromagnetic radiation theory. Diffraction radiation is generated when a charged particle moves in a vacuum near a target edge. Diffraction radiation of non-relativistic particles is widely used to design intense emitters in the cm wavelength range. Diffraction radiation from relativistic charged particles is important for noninvasive beam diagnostics and design of free electron lasers based on Smith-Purcell radiation which is diffraction radiation from periodic structures. Different analytical models of diffraction radiation and results of recent experimental studies are presented in this book. The book may also serve as guide to classical electrodynamics applications in beam physics and electrodynamics. It can be of great use for young researchers to develop skills and for experienced scientists to obtain new results.
Diffraction radiation from relativistic particles
International Nuclear Information System (INIS)
Potylitsyn, Alexander Petrovich; Ryazanov, Mikhail Ivanovich; Strikhanov, Mikhail Nikolaevich; Tishchenko, Alexey Alexandrovich
2010-01-01
This book deals with diffraction radiation, which implies the boundary problems of electromagnetic radiation theory. Diffraction radiation is generated when a charged particle moves in a vacuum near a target edge. Diffraction radiation of non-relativistic particles is widely used to design intense emitters in the cm wavelength range. Diffraction radiation from relativistic charged particles is important for noninvasive beam diagnostics and design of free electron lasers based on Smith-Purcell radiation which is diffraction radiation from periodic structures. Different analytical models of diffraction radiation and results of recent experimental studies are presented in this book. The book may also serve as guide to classical electrodynamics applications in beam physics and electrodynamics. It can be of great use for young researchers to develop skills and for experienced scientists to obtain new results. (orig.)
Analytic approaches to relativistic hydrodynamics
Energy Technology Data Exchange (ETDEWEB)
Hatta, Yoshitaka
2016-12-15
I summarize our recent work towards finding and utilizing analytic solutions of relativistic hydrodynamic. In the first part I discuss various exact solutions of the second-order conformal hydrodynamics. In the second part I compute flow harmonics v{sub n} analytically using the anisotropically deformed Gubser flow and discuss its dependence on n, p{sub T}, viscosity, the chemical potential and the charge.
International Nuclear Information System (INIS)
Cardoso, Vitor; Lemos, Jose P.S.; Yoshida, Shijun
2003-01-01
We investigate the electromagnetic radiation released during the high energy collision of a charged point particle with a four-dimensional Schwarzschild black hole. We show that the spectra is flat, and well described by a classical calculation. We also compare the total electromagnetic and gravitational energies emitted, and find that the former is suppressed in relation to the latter for very high energies. These results could apply to the astrophysical world in the case that charged stars and small charged black holes are out there colliding into large black holes, and to a very high energy collision experiment in a four-dimensional world. In this latter scenario the calculation is to be used for the moments just after black hole formation, when the collision of charged debris with the newly formed black hole is certainly expected. Since the calculation is four dimensional, it does not directly apply to TeV-scale gravity black holes, as these inhabit a world of six to eleven dimensions, although our results should qualitatively hold when extrapolated with some care to higher dimensions
International Nuclear Information System (INIS)
Nemenov, L.
2001-01-01
The Coulomb interaction which occurs in the final state between two particles with opposite charges allows for creation of the bound state of these particles. In the case when particles are generated with large momentum in lab frame, the Lorentz factors of the bound state will also be much larger than one. The relativistic velocity of the atoms provides the opportunity to observe bound states of (π + μ - ), (π + π - ) and (π + K - ) with a lifetime as short as 10 -16 s, and to measure their parameters. The ultrarelativistic positronium atoms (A 2e ) allow us to observe the e.ect of superpenetration in matter, to study the effects caused by the formation time of A 2e from virtual e + e - pairs and to investigate the process of transformation of two virtual particles into the bound state
Nuclear-breakup mechanisms in the interaction of relativistic projectiles with heavy targets
International Nuclear Information System (INIS)
Steinberg, E.P.
1982-01-01
The breakup of a Au nucleus under bombardment with relativistic p, α, and 20 Ne has been investigated in an extensive, multi-detector study. The present discussion addresses some of the many aspects of the experimental results. A broad distribution of coincident fragment masses is observed, with the total fragment kinetic energy being higher than expected for a fission mechanism for total fragment mass less than or equal to 120. The formation of light fragments is shown to be inconsistent with a binary breakup mechanism, and a multi-fragment target breakup is suggested. In general, the results indicate a broad spectrum of violence in the collisions, from gentle, leading to the production of heavy spallation products and fission, to essentially explosive, leading to multi-fragment breakup into light mas products. These aspects of the reactions represent a late-stage breakup of the target residues and are positively correlated with the violence of the initial fast stage of the collision as measured by the charged particle multiplicity
Bhattacharya, Atanu; Bernstein, Elliot R
2011-10-06
The radical cationic reactivity of the peptide analogue molecule CH(3)CO-Gly-NH(2) is addressed both experimentally and theoretically. The radical cation intermediate of CH(3)CO-Gly-NH(2) is created by single-photon ionization of this molecule at 118.22 nm (~10.5 eV). The two most stable conformers (C(7) and C(5)) of this molecule exhibit different folds along the backbone: the C(7) conformer has a γ-turn structure, and the C(5) conformer has a β-strand structure. The experimental results show that the radical cation intermediate of CH(3)CO-Gly-NH(2) dissociates and generates a fragment-ion signal at 73 amu that is observed through TOFMS. Theoretical results show how the fragment-ion signal at 73 amu is generated by only one conformer of CH(3)CO-Gly-NH(2) (C(7)) and how local charge and specific hydrogen bonding in the molecule influence fragmentation of the radical cation intermediate of CH(3)CO-Gly-NH(2). The specific fold of the molecule controls fragmentation of this reactive radical cation intermediate. Whereas the radical cation of the C(7) conformer dissociates through a hydrogen-transfer mechanism followed by HNCO elimination, the radical cation of the C(5) conformer does not dissociate at all. CASSCF calculations show that positive charge in the radical cationic C(7) conformer is localized at the NH(2)CO moiety of the molecular ion. This site-specific localization of the positive charge enhances the acidity of the terminal NH(2) group, facilitating hydrogen transfer from the NH(2) to the COCH(3) end of the molecular ion. Positive charge in the C(5) conformer of the CH(3)CO-Gly-NH(2) radical cation is, however, localized at the COCH(3) end of the molecular ion, and this conformer does not have enough energy to surmount the energy barrier to dissociation on the ion potential energy surface. CASSCF results show that conformation-specific localization of charge in the CH(3)CO-Gly-NH(2) molecular ion occurs as a result of the different hydrogen
Azimuthal Anisotropies in Nuclear Fragmentation
International Nuclear Information System (INIS)
Dabrowska, A.; Szarska, M.; Trzupek, A.; Wolter, W.; Wosiek, B.
2002-01-01
The directed and elliptic flow of fragments emitted from the excited projectile nuclei has been observed for 158 AGeV Pb collisions with the lead and plastic targets. For comparison the flow analysis has been performed for 10.6 AGeV Au collisions with the emulsion target. The strong directed flow of heaviest fragments is found. Light fragments exhibit directed flow opposite to that of heavy fragments. The elliptic flow for all multiply charged fragments is positive and increases with the charge of the fragment. The observed flow patterns in the fragmentation of the projectile nucleus are practically independent of the mass of the target nucleus and the collision energy. Emission of fragments in nuclear multifragmentation shows similar, although weaker, flow effects. (author)
Multifragmentation in relativistic heavy ion reactions
International Nuclear Information System (INIS)
Trautmann, W.
1996-11-01
Multifragmentation is the dominant decay mode of heavy nuclear systems with excitation energies in the vicinity of their binding energies. It explores the partition space associated with the number of nucleonic constituents and it is characterized by a multiple production of nuclear fragments with intermediate mass. Reactions at relativistic bombarding energies, exceeding several hundreds of MeV per nucleon, have been found very efficient in creating such highly excited systems. Peripheral collisions of heavy symmetric systems or more central collisions of mass asymmetric systems produce spectator nuclei with properties indicating a high degree of equilibration. The observed decay patterns are well described by statistical multifragmentation models. The present experimental and theoretical studies are particularly motivated by the fact that multifragmentation is being considered a possible manifestation of the liquid-gas phase transition in finite nuclear systems. From the simultaneous measurement of the temperature and of the energy content of excited spectator systems a caloric curve of nuclei has been obtained. The characteristic S-shaped behavior resembles that of ordinary liquids. Signatures of critical phenomena in finite nuclear systems are searched for in multifragmentation data. These studies, supported by the success of percolation in reproducing the experimental mass or charge correlations, concentrate on the fluctuations observed in these observables. Attempts have been made to deduce critical-point exponents associated with multifragmentation. (orig.)
Universality of projectile fragmentation model
International Nuclear Information System (INIS)
Chaudhuri, G.; Mallik, S.; Das Gupta, S.
2012-01-01
Presently projectile fragmentation reaction is an important area of research as it is used for the production of radioactive ion beams. In this work, the recently developed projectile fragmentation model with an universal temperature profile is used for studying the charge distributions of different projectile fragmentation reactions with different projectile target combinations at different incident energies. The model for projectile fragmentation consists of three stages: (i) abrasion, (ii) multifragmentation and (iii) evaporation
Collective phenomena in relativistic heavy-ion collisions
Wang, Shan
1998-12-01
Collective motion in the final state of relativistic nucleus-nucleus collisions, produced by the release of compressional energy built-up during the stage of maximum density, is widely accepted as a good observable to test models and a useful tool to probe the nuclear equation of state. This dissertation presents an experimental study of nuclear collisions at the Bevalac accelerator at Lawrence Berkeley National Laboratory, with special emphasis on collective phenomena. The main detector used is a time projection chamber with more than two million pixels. Using high statistics measurements of all charged final- state fragments in Au + Au reactions at 0.25, 0.4, 0.6, 0.8, 1.0, and 1.15A GeV, we present a new method to unify the description of light fragment spectra and the three main categories of collective motion: sideward flow, squeeze-out, and transverse expansion. In this alternative representation, the speed of collective expansion is shown to be slowest in the plane of the reaction, and is modulated sinusoidally according to fragment azimuth relative to this plane. This simple yet complete characterization of squeeze-out leads to its interpretation as an in-plane retardation of collective expansion. We test momentum space power law behavior by studying the momentum-space densities of fragments up to 4He. We conclude that the simple momentum-space power law consistently describes light participant fragment production at p⊥/A/ge0.2 GeV/c over a remarkably wide range of transverse momentum, azimuth relative to the reaction plane, rapidity, multiplicity and beam energy in intermediate-energy heavy-ion collisions and in particular, the increase in sideward flow with fragment mass is well described by a momentum- space power law under these conditions. This behavior is consistent with composite fragment formation through a statistical coalescence mechanism in momentum space. Our conclusion supports the use of models without composite formation to interpret flow
The relativistic virial theorem
International Nuclear Information System (INIS)
Lucha, W.; Schoeberl, F.F.
1989-11-01
The relativistic generalization of the quantum-mechanical virial theorem is derived and used to clarify the connection between the nonrelativistic and (semi-)relativistic treatment of bound states. 12 refs. (Authors)
Relativistic Boltzmann theory for a plasma
International Nuclear Information System (INIS)
Erkelens, H. van.
1984-01-01
This thesis gives a self-contained treatment of the relativistic Boltzmann theory for a plasma. Here plasma means any mixture containing electrically charged particles. The relativistic Boltzmann equation is linearized for the case of a plasma. The Chapman-Enskog method is elaborated further for transport phenomena. Linear laws for viscous phenomena are derived. Then the collision term in the Boltzmann theory is dealt with. Using the transport equation, a kinetic theory of wave phenomena is developed and the dissipation of hydromagnetic waves in a relativistic plasma is investigated. In the final chapter, it is demonstrated how the relativistic Boltzmann theory can be applied in cosmology. In doing so, expressions are derived for the electric conductivity of the cosmological plasma in the lepton era, the plasma era and the annihilation era. (Auth.)
International Nuclear Information System (INIS)
Er-Qin, Wang; Fu-Hu, Liu; Jian-Xin, Sun; Rahim, Magda A.; Fakhraddin, S.
2011-01-01
The multiplicity distributions of projectile fragments emitted in interactions of different nuclei with emulsion are studied by using a multi-source model. Our calculated results show that the projectile fragments can be described by the model and each source contributes an exponential distribution. As the weighted sum of the folding result of many exponential distributions, a multi-component Erlang distribution is used to describe the experimental data. The relationship between the height (or width) of the distribution and the mass of the incident projectile, as well as the dependence of projectile fragments on target groups, are investigated too. (nuclear physics)
International Nuclear Information System (INIS)
Sokolov, A.
1990-05-01
This work is a contribution to the study of the formation and decay of hot nuclei produced in heavy ion collisions at intermediate energies. By studying the system Ar + Au and Ar + Th at 44 MeV/u and 77 MeV/u we first show how to classify events in two groups: peripheral and very dissipative collisions, measuring the number of evaporated neutrons, which depend directly on the violence of the collision. Associated with these neutrons, different deexcitation channels were observed (heavy residues, fission fragments, light charged particles, intermediate mass fragments). The ratio between peripheral and very dissipative collisions was found independent of the system and the same as the one observed at lower incident energy. The most probable neutron multiplicity for very dissipative collisions is not very different at 44 MeV/u and 77 MeV/u. A measurement of the angular distribution of fission fragments and heavy residues was performed. Detected products are essentially associated with large neutron multiplicity and have a cross section close to the one for the very dissipative collisions. The total mass of the fission fragments is close to the mass of the target, while the mass of the heavy residue is much smaller. The backward evaporated light charged particles are also produced in very dissipative collisions. The characteristics of their energy spectra as well as their multiplicities are very similar at 44 MeV/u 77 MeV/u. From the number of evaporated light charged particles, the estimation of the quasi-target excitation energy was done and found to be close to 600 MeV at 44 MeV/u and 77 MeV/u [fr
Relativistic electron beams above thunderclouds
DEFF Research Database (Denmark)
Füellekrug, M.; Roussel-Dupre, R.; Symbalisty, E. M. D.
2011-01-01
Non-luminous relativistic electron beams above thunderclouds have been detected by the radio signals of low frequency similar to 40-400 kHz which they radiate. The electron beams occur similar to 2-9 ms after positive cloud-to-ground lightning discharges at heights between similar to 22-72 km above...... thunderclouds. Intense positive lightning discharges can also cause sprites which occur either above or prior to the electron beam. One electron beam was detected without any luminous sprite which suggests that electron beams may also occur independently of sprites. Numerical simulations show that beams...... of electrons partially discharge the lightning electric field above thunderclouds and thereby gain a mean energy of similar to 7MeV to transport a total charge of similar to-10mC upwards. The impulsive current similar to 3 x 10(-3) Am-2 associated with relativistic electron beams above thunderclouds...
The program LISE: a simulation of fragment separators
International Nuclear Information System (INIS)
Bazin, D.; Tarasov, O.; Lewitowicz, M.; Sorlin, O.
2001-01-01
The program LISE, which simulates the operation of fragment separators, used in the production of radioactive beams via fragmentation is described. Various aspects of the physical phenomenon involved in the production of such radioactive beams are discussed. They include fragmentation cross sections, energy losses in materials, ionic charge state distributions, as well as ion optics calculations and acceptance effects. Among the goals of this program is a highly user-friendly environment, designed not only to forecast intensities and purities for future experiments, but also as a tuning tool during experiments where its results can be quickly compared to on-line data. In addition, several general purpose tools such as a physical parameters calculator, a database of nuclei properties, and relativistic two-body kinematics calculations make it also attractive in experiments where radioactive beams are not involved. After a general description of fragment separators, the principles underlying the calculations are presented, followed by a practical description of the program and its many features. Finally, a few examples of calculations are compared to on-line data, both qualitatively and quantitatively
Energy Technology Data Exchange (ETDEWEB)
Karev, A G; Morozov, B A; Petukhov, Yu P; Povtorejko, A A; Sukhanov, A Yu [Joint Inst. for Nuclear Research, Dubna (USSR)
1989-01-01
Analysis of the Cherenkov spectrometer results on the fragmentation of the magnesium nuclei with momenta 4.5A GeV/c interacting with plexiglas show the presence of a short-range component in the fragment absorption function. For fragments with Z=6-10 (Z is the charge) the mean free paths in plexiglas for normal and anomalous component are estimated to be {lambda}{sub n}=141.7 {plus minus} 1.9 mm and {lambda}{sub a}=1.9 {plus minus} 0.8 mm. The anomalous component admixture at fixed {lambda}{sub a}=2 mm is {alpha}=0.084 {plus minus} 0.027. The parameter estimates are stable for various criteria applied to selecting the events.
Quadratic hamiltonians and relativistic quantum mechanics
International Nuclear Information System (INIS)
Razumov, A.V.; Solov'ev, V.O.; Taranov, A.Yu.
1981-01-01
For the case of a charged scalar field described by a quadratic hamiltonian the equivalent relativistic quantum mechanics is constructed in one-particle sector. Complete investigation of a charged relativistic particle motion in the Coulomb field is carried out. Subcritical as well as supercritical cases are considered. In the course of investigation of the charged scalar particle in the Coulomb field the diagonalization of the quadratic hamiltonian describing the charged scalar quantized field interaction with the external Coulomb field has taken place. Mathematically this problem is bound to the construction of self-conjugated expansions of the symmetric operator. The construction of such expansion is necessary at any small external field magnitude [ru
Relativistic generalization of the Newtonian force
International Nuclear Information System (INIS)
Qadir, A.; Quamar, J.
1982-06-01
Whereas there is no denying the essential contribution of geometrodynamics, it must be admitted that our physical intuition is still firmly based in the Newtonian concept of force. Here we extend some earlier work re-introducing the Newtonian force concept into relativity theory. Some fundamentally new insights into the relativistic effects due to charge and rotation are presented. (author)
Extended Galilean symmetries of non-relativistic strings
Energy Technology Data Exchange (ETDEWEB)
Batlle, Carles [Departament de Matemàtiques and IOC, Universitat Politècnica de Catalunya, EPSEVG,Av. V. Balaguer 1, E-08808 Vilanova i la Geltrú (Spain); Gomis, Joaquim; Not, Daniel [Departament de Física Quàntica i Astrofísica and Institut de Ciències del Cosmos (ICCUB),Universitat de Barcelona,Martí i Franquès 1, E-08028 Barcelona (Spain)
2017-02-09
We consider two non-relativistic strings and their Galilean symmetries. These strings are obtained as the two possible non-relativistic (NR) limits of a relativistic string. One of them is non-vibrating and represents a continuum of non-relativistic massless particles, and the other one is a non-relativistic vibrating string. For both cases we write the generator of the most general point transformation and impose the condition of Noether symmetry. As a result we obtain two sets of non-relativistic Killing equations for the vector fields that generate the symmetry transformations. Solving these equations shows that NR strings exhibit two extended, infinite dimensional space-time symmetries which contain, as a subset, the Galilean symmetries. For each case, we compute the associated conserved charges and discuss the existence of non-central extensions.
Energy Technology Data Exchange (ETDEWEB)
Gomez R, F
2004-07-01
In the chapter 1 we show the foundations of the special relativity in the frame of the classical mechanics and we develop the necessary theory for the theoretical description of the relativistic dynamics of charged particles in the interaction with electromagnetic fields. It will see that starting from the energy conservation principle is derived the Einstein's law that establishes the relationship among this and the mass. Later on, it will take the action of a charged particle in a given radiation field and in the one which only we will take two parts, the action of the free particle and the one that defines the interaction of this with the field. The equations of motion of a charge in an electromagnetic field come given by the Lagrange equations, being obtained an expression for the force, well-known as Lorentz force, which consists of two terms, the first of them is the force that the electric field E exercises on the particle; which doesn't depend on the charge speed and is oriented in the direction of the field, the second term represents the force that exercises the magnetic field B and that it is proportional to the charge speed, being perpendicular to the direction of it. In the chapter 2 an integration method of the Hamilton-Jacobi for the case of a pulse is that allows to found analytical forms for the moment, the energy and the charge position is developed with detail. We will present, also, a discussion of the classical theory of the relativistic dynamic of free electrons. They are also obtained, invariant quantities like the phase, before the frame of the reference inertial changes, well-known as Lorentz invariants of the system. In this part it is considered to the electron in the laboratory frame (frame in which the particle is initially in repose regarding the observer), of which the speed and the acceleration quadrivectors can be calculated. We demonstrate that the {eta} phase is a Lorentz invariant. It is shown, also that the proper time
International Nuclear Information System (INIS)
Rentenier, A; Bordenave-Montesquieu, D; Moretto-Capelle, P; Bordenave-Montesquieu, A
2003-01-01
Multifragmentation and asymmetric fission (AF) of the C 60 molecule induced by H + , H 2 + , H 3 + and He + ions at medium collision energies (2-130 keV) are considered. Momenta and kinetic energies of C n + fragment ions (n = 1- 12) are deduced from an analysis of time-of-flight spectra. In multifragmentation processes, momenta are found to be approximately constant when n > 2, a behaviour which explains that the most probable kinetic energy, as well as the width of the kinetic energy distributions, is found to be inversely proportional to the fragment size n; both momenta and kinetic energies are independent of the velocity and nature of the projectile, and hence of the energy deposit. A specific study of the AF shows that the kinetic energies of C 2 + , C 4 + and C 6 + fragments are also independent of the collision velocity and projectile species; a quantitative agreement is found with values deduced from kinetic energy release measurements by another group in electron impact experiments, and the observed decrease when the mass of the light fragment increases is also reproduced. A quantitative comparison of AF and multifragmentation for the n = 2, 4 and 6 fragment ions shows that kinetic energies in AF exceed that in multifragmentation, a result which explains the oscillations observed when momenta or kinetic energies of fragments are plotted against the n-value. The AF yield is also found to scale with the energy deposit in the collision velocity range extending below the velocity at the maximum of the electronic stopping power; except for protons, it remains negligible with respect to multifragmentation as soon as the total energy deposit exceeds about 100 eV
Thermodynamics of polarized relativistic matter
Energy Technology Data Exchange (ETDEWEB)
Kovtun, Pavel [Department of Physics and Astronomy, University of Victoria,PO Box 1700 STN CSC, Victoria BC, V8W 2Y2 (Canada)
2016-07-05
We give the free energy of equilibrium relativistic matter subject to external gravitational and electromagnetic fields, to one-derivative order in the gradients of the external fields. The free energy allows for a straightforward derivation of bound currents and bound momenta in equilibrium. At leading order, the energy-momentum tensor admits a simple expression in terms of the polarization tensor. Beyond the leading order, electric and magnetic polarization vectors are intrinsically ambiguous. The physical effects of polarization, such as the correlation between the magneto-vortically induced surface charge and the electro-vortically induced surface current, are not ambiguous.
International Nuclear Information System (INIS)
Pellereau, Eric
2013-01-01
The isotopic fission yields of U 238 following the SOFIA experiment, conducted at the GSI facility (Darmstadt), are presented here. This experiment takes advantage of the inverse kinematics technique at relativistic energies. Benefits are several: fission fragments are highly focused (high geometrical efficiency) and are also completely stripped, which greatly simplifies their nuclear charge measurement. The first detector of the SOFIA setup is an active target in which fission occurs via electromagnetic excitation, followed by an ionization chamber to measure the nuclear charge and the horizontal angle of both fission fragments. The masses are deduced by the bending radius measurement of the fragments, deflected by a strong magnet (ALADIN), thanks to two position detectors (MWPC), and also by a highly resolved time-of-flight measurement (40 ps FWHM) so that heavy neighboring isotopes can be separated. The data analysis shows that the main goals are achieved since the isotopic separation is reached over the whole range of the fission fragments. A strong even-odd effect is seen in the charge spectrum, which also exhibits a mean heavy charge close to Z = 54. Surprisingly, the neutron even-odd effect of the light region is seen to be very close to the one in thermal neutron induced fission. The peak-to-valley ratio of the mass spectrum confirms that the mean excitation energy at fission is close to the expected one (14 MeV). The GEF code is used for comparison and always gives results very close to ours. (author) [fr
Relativistic Linear Restoring Force
Clark, D.; Franklin, J.; Mann, N.
2012-01-01
We consider two different forms for a relativistic version of a linear restoring force. The pair comes from taking Hooke's law to be the force appearing on the right-hand side of the relativistic expressions: d"p"/d"t" or d"p"/d["tau"]. Either formulation recovers Hooke's law in the non-relativistic limit. In addition to these two forces, we…
Impossibility of an acyclic relativistic electric motor
Energy Technology Data Exchange (ETDEWEB)
Spavieri, G [Universidad de Los Andes, Merida (Venezuela); Cavalleri, G [Milan Univ. (Italy). Ist. di Fisica; Spinelli, G [Padua Univ. (Italy). Ist. di Matematica Applicata
1981-02-11
The relativistic torque acting on a circuit carrying a current and having a uniform translatory motion in a constant and uniform electric field would seem to suggest the possibility of an acyclic relativistic electric motor. However, the net effect on the side parallel to the rotation axis is exactly balanced by the variation of the angular momentum (in the case of an insulating circuit transporting electric charges) or by the external moment due to the magnetic field (in the case of a conducting circuit) acting on the two sides perpendicular to the rotation axis.
Relativistic impulse approximation and deuteron spin structure
International Nuclear Information System (INIS)
Tokarev, M.V.
1992-01-01
The fragmentation processes were considered of tensor- and vector-polarized deuterons to protons in the framework of the covariant approach in the light cone variables on the basis of the relativistic deuteron wave function with one nucleon on-mass shell. The experimental verification of predicted dependences of T 20 and K is of interest for the research of the momentum and spin distributions of high momentum deuteron constituents. 21 refs.; 6 figs
Studying extremely peripheral collisions of relativistic heavy ions
International Nuclear Information System (INIS)
Fatyga, M.
1990-01-01
Relativistic heavy ion facilities have been proposed (and in some cases constructed) with an intent to search for a new state of matter, a quark gluon plasma. As with all tools in the experimental physics, one should always search for ways in which relativistic heavy ions can be used to study physical phenomena beyond this original goal. New possibilities for a study of higher order photonuclear excitations in extremely peripheral collisions of relativistic heavy ions are discussed in this contribution. Data on the electromagnetic and nuclear fragmentation of a 14.6Gev/nucleon 28 Si projectile are presented
International Nuclear Information System (INIS)
Mittelstaedt, P.
1983-01-01
on the basis of the well-known quantum logic and quantum probability a formal language of relativistic quantum physics is developed. This language incorporates quantum logical as well as relativistic restrictions. It is shown that relativity imposes serious restrictions on the validity regions of propositions in space-time. By an additional postulate this relativistic quantum logic can be made consistent. The results of this paper are derived exclusively within the formal quantum language; they are, however, in accordance with well-known facts of relativistic quantum physics in Hilbert space. (author)
Relativistic quantum mechanics; Mecanique quantique relativiste
Energy Technology Data Exchange (ETDEWEB)
Ollitrault, J.Y. [CEA Saclay, 91 - Gif-sur-Yvette (France). Service de Physique Theorique]|[Universite Pierre et Marie Curie, 75 - Paris (France)
1998-12-01
These notes form an introduction to relativistic quantum mechanics. The mathematical formalism has been reduced to the minimum in order to enable the reader to calculate elementary physical processes. The second quantification and the field theory are the logical followings of this course. The reader is expected to know analytical mechanics (Lagrangian and Hamiltonian), non-relativistic quantum mechanics and some basis of restricted relativity. The purpose of the first 3 chapters is to define the quantum mechanics framework for already known notions about rotation transformations, wave propagation and restricted theory of relativity. The next 3 chapters are devoted to the application of relativistic quantum mechanics to a particle with 0,1/5 and 1 spin value. The last chapter deals with the processes involving several particles, these processes require field theory framework to be thoroughly described. (A.C.) 2 refs.
Effects of relativistic small radial component on atomic photoionization cross sections
International Nuclear Information System (INIS)
Liu Xiaobin; Xing Yongzhong; Sun Xiaowei
2008-01-01
The effects of relativistic small radial component on atomic photoionization cross sections have been studied within relativistic average self-consistent field theory. Relativistic effects are relatively unimportant for low photon energy, along with a review of high-energy photoionization the relativistic effects are quite important. The effects of relativistic small radial component on photoionization process should show breakdown when the nuclear finite-size effects is taken into account. The compression of wavefunction into the space near nucleus is so strong in highly charged ions that the electronic radius greatly decreases, and the effects of relativistic small radial component on photoionization cross sections turn to stronger than ordinary atoms. Since relativistic effects are extremely sensitive to the behavior of small radial component, the results are in good agreement with relativistic effects on photoionization cross section. (authors)
Towards relativistic quantum geometry
Energy Technology Data Exchange (ETDEWEB)
Ridao, Luis Santiago [Instituto de Investigaciones Físicas de Mar del Plata (IFIMAR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mar del Plata (Argentina); Bellini, Mauricio, E-mail: mbellini@mdp.edu.ar [Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3350, C.P. 7600, Mar del Plata (Argentina); Instituto de Investigaciones Físicas de Mar del Plata (IFIMAR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mar del Plata (Argentina)
2015-12-17
We obtain a gauge-invariant relativistic quantum geometry by using a Weylian-like manifold with a geometric scalar field which provides a gauge-invariant relativistic quantum theory in which the algebra of the Weylian-like field depends on observers. An example for a Reissner–Nordström black-hole is studied.
Norbury, John W.
1992-01-01
Nuclear fission reactions induced by the electromagnetic field of relativistic nuclei are studied for energies relevant to present and future relativistic heavy ion accelerators. Cross sections are calculated for U-238 and Pu-239 fission induced by C-12, Si-28, Au-197, and U-238 projectiles. It is found that some of the cross sections can exceed 10 b.
Relativistic Shock Acceleration
International Nuclear Information System (INIS)
Duffy, P.; Downes, T.P.; Gallant, Y.A.; Kirk, J.G.
1999-01-01
In this paper we briefly review the basic theory of shock waves in relativistic hydrodynamics and magneto-hydrodynamics, emphasising some astrophysically interesting cases. We then present an overview of the theory of particle acceleration at such shocks describing the methods used to calculate the spectral indices of energetic particles. Recent results on acceleration at ultra-relativistic shocks are discussed. (author)
International Nuclear Information System (INIS)
Chung, K.C.
1989-01-01
An introduction to nuclear fragmentation, with emphasis in percolation ideas, is presented. The main theoretical models are discussed and as an application, the uniform expansion approximation is presented and the statistical multifragmentation model is used to calculate the fragment energy spectra. (L.C.)
Chaos and maps in relativistic rynamical systems
Directory of Open Access Journals (Sweden)
L. P. Horwitz
2000-01-01
Full Text Available The basic work of Zaslavskii et al showed that the classical non-relativistic electromagnetically kicked oscillator can be cast into the form of an iterative map on the phase space; the resulting evolution contains a stochastic flow to unbounded energy. Subsequent studies have formulated the problem in terms of a relativistic charged particle in interaction with the electromagnetic field. We review the structure of the covariant Lorentz force used to study this problem. We show that the Lorentz force equation can be derived as well from the manifestly covariant mechanics of Stueckelberg in the presence of a standard Maxwell field, establishing a connection between these equations and mass shell constraints. We argue that these relativistic generalizations of the problem are intrinsically inaccurate due to an inconsistency in the structure of the relativistic Lorentz force, and show that a reformulation of the relativistic problem, permitting variations (classically in both the particle mass and the effective “mass” of the interacting electromagnetic field, provides a consistent system of classical equations for describing such processes.
Sun, Dong; Meng, Xiangjun; Ren, Tianming; Fawcett, John Paul; Wang, Hualu; Gu, Jingkai
2018-04-01
Sensitivity is generally an issue in bioassays of prostaglandins and their synthetic analogs due to their extremely low concentration in vivo. To improve the ionization efficiency of limaprost, an oral prostaglandin E1 (PGE1) synthetic analog, we investigated a charge reversal derivatization strategy in electrospray ionization mass spectrometry (ESI-MS). We established that the cholamine derivative exhibits much greater signal intensity in the positive-ion mode compared with limaprost in the negative ion mode. Collision-induced dissociation (CID) involved exclusive neutral mass loss and positive charge migration to form stable cationic product ions with the positive charge on the limaprost residue rather than on the modifying group. This has the effect of maintaining the efficiency and specificity of multiple reaction monitoring (MRM) and avoiding cross talk. CID fragmentation patterns of other limaprost derivatives allowed us to relate the dissociation tendency of different neutral leaving groups to an internal energy distribution scale based on the survival yield method. Knowledge of the energy involved in the production of stabilized positive ions will potentially assist the selection of suitable derivatization reagents for the analysis of a wide variety of lipid acids. [Figure not available: see fulltext.
Vereshchagin, Gregory V.; Aksenov, Alexey G.
2017-02-01
Preface; Acknowledgements; Acronyms and definitions; Introduction; Part I. Theoretical Foundations: 1. Basic concepts; 2. Kinetic equation; 3. Averaging; 4. Conservation laws and equilibrium; 5. Relativistic BBGKY hierarchy; 6. Basic parameters in gases and plasmas; Part II. Numerical Methods: 7. The basics of computational physics; 8. Direct integration of Boltzmann equations; 9. Multidimensional hydrodynamics; Part III. Applications: 10. Wave dispersion in relativistic plasma; 11. Thermalization in relativistic plasma; 12. Kinetics of particles in strong fields; 13. Compton scattering in astrophysics and cosmology; 14. Self-gravitating systems; 15. Neutrinos, gravitational collapse and supernovae; Appendices; Bibliography; Index.
Velocity determination of neutron-rich projectile fragments with a ring-imaging Cherenkov detector
International Nuclear Information System (INIS)
Zeitelhack, K.
1992-11-01
For the velocity determination of relativistic heavy ions (A>100) in the energy range 300A.MeV ≤ E kin ≤ 2A.GeV a highly resolving, compact ring-imaging Cherenkov counter with large dynamical measurement range was developed. The Cherenkov light cone emitted in the flight of a relativistic heavy ion by a liquid layer (C 6 F 14 ) is focused on the entrance window of a one-dimensional position-resolving VUV-sensitive photon detector. This gas detector is operated at atmospheric pressure with a mixture of 90% methane and 10% isobutane with 0.04% TMAE as photosensitive admixture. For 725A.MeV 129 Xe ions a velocity resolution Δβ/β=1.8.10 -3 and a nuclear charge-number resolution ΔZ/Z=5.1.10 -2 was reached. The over the photon energy range 5.4 eV ≤ E γ ≤ 7.2 eV averaged detection efficiency of the detector system was determined to ε tot =2.8%>. At the 0deg magnet spectrometer Fragmentseparator of the GSI Darmstadt the RICH detector was for the first time applied for the identification of nuclear charge number and mass of heavy relativistic projectile fragments. In the experiment the production cross sections of very neutron-rich nuclei by fragmentation of 136 Xe projectiles in the reaction 76A.MeV 136 Xe on 27 Al were determined. From the measured production erates for the production of the double-magic nucleus 132 Zn in this reaction a cross section of σ=(0.4± 0.3 0.6 ) μbarn can be extrapolated. (orig./HSI) [de
International Nuclear Information System (INIS)
Karnaukhov, V.A.; Avdeev, S.P.; Kuznetsov, V.D.
1998-01-01
The experimental data on fragment multiplicities, their energy and charge distributions, the emission times are considered for the nuclear multifragmentation process induced by relativistic light projectiles (protons, helium) and heavy ions. With light projectiles, the multifragmentation is a pure 'thermal' process, well described by the statistical models. Heavy-ion-induced multifragmentation is influenced by dynamic effects related first of all to the compression of the system in the collision. But statistical models can also be applied to rendering the partition of the system if the excitation energy is less than 10 MeV/nucleon and compression is modest. For the central collision of heavy ions the statistical approach fails to describe the data
Virtual fragment preparation for computational fragment-based drug design.
Ludington, Jennifer L
2015-01-01
Fragment-based drug design (FBDD) has become an important component of the drug discovery process. The use of fragments can accelerate both the search for a hit molecule and the development of that hit into a lead molecule for clinical testing. In addition to experimental methodologies for FBDD such as NMR and X-ray Crystallography screens, computational techniques are playing an increasingly important role. The success of the computational simulations is due in large part to how the database of virtual fragments is prepared. In order to prepare the fragments appropriately it is necessary to understand how FBDD differs from other approaches and the issues inherent in building up molecules from smaller fragment pieces. The ultimate goal of these calculations is to link two or more simulated fragments into a molecule that has an experimental binding affinity consistent with the additive predicted binding affinities of the virtual fragments. Computationally predicting binding affinities is a complex process, with many opportunities for introducing error. Therefore, care should be taken with the fragment preparation procedure to avoid introducing additional inaccuracies.This chapter is focused on the preparation process used to create a virtual fragment database. Several key issues of fragment preparation which affect the accuracy of binding affinity predictions are discussed. The first issue is the selection of the two-dimensional atomic structure of the virtual fragment. Although the particular usage of the fragment can affect this choice (i.e., whether the fragment will be used for calibration, binding site characterization, hit identification, or lead optimization), general factors such as synthetic accessibility, size, and flexibility are major considerations in selecting the 2D structure. Other aspects of preparing the virtual fragments for simulation are the generation of three-dimensional conformations and the assignment of the associated atomic point charges.
Using MUSIC to study relativistic nuclear collisions
International Nuclear Information System (INIS)
1983-01-01
A large Multiple Sampling Ionization Chamber (MUSIC) has been developed as a part of the Heavy Ion Spectrometer System (HISS). This facility is being used for the study of relativistic nuclear collisions at the Bevalac of Lawrence Berkeley Laboratory. Preliminary data from MUSIC indicate that a charge resolution of one unit should be achieved from Z approximately equal to 7 to Z approximately equal to 100. (author)
Relativistic nuclear photographic emulsion for multilayer piles
International Nuclear Information System (INIS)
Bogomolov, K.S.; Romanovskaya, K.M.; Razorenova, I.F.
1975-01-01
Nuclear photoemulsion layers having a high sensitivity to relativistic singly charged particles, a high sensitivity stability, time stability of the latent image, as well as a high constancy of the emulsion thickness within the limits of the layer, were developed and fabricated for a large nuclear photoemulsion stack that was exposed in space during the experiments carried out on the artificial earth satellite ''Intercosmos-6''
Plasma relativistic microwave electronics
International Nuclear Information System (INIS)
Kuzelev, M.V.; Loza, O.T.; Rukhadze, A.A.; Strelkov, P.S.; Shkvarunets, A.G.
2001-01-01
One formulated the principles of plasma relativistic microwave electronics based on the induced Cherenkov radiation of electromagnetic waves at interaction of a relativistic electron beam with plasma. One developed the theory of plasma relativistic generators and accelerators of microwave radiation, designed and studied the prototypes of such devices. One studied theoretically the mechanisms of radiation, calculated the efficiencies and the frequency spectra of plasma relativistic microwave generators and accelerators. The theory findings are proved by the experiment: intensity of the designed sources of microwave radiation is equal to 500 μW, the frequency of microwave radiation is increased by 7 times (from 4 up to 28 GHz), the width of radiation frequency band may vary from several up to 100%. The designed sources of microwave radiation are no else compared in the electronics [ru
Energy Technology Data Exchange (ETDEWEB)
Antippa, Adel F [Departement de Physique, Universite du Quebec a Trois-Rivieres, Trois-Rivieres, Quebec G9A 5H7 (Canada)
2009-05-15
We solve the problem of the relativistic rocket by making use of the relation between Lorentzian and Galilean velocities, as well as the laws of superposition of successive collinear Lorentz boosts in the limit of infinitesimal boosts. The solution is conceptually simple, and technically straightforward, and provides an example of a powerful method that can be applied to a wide range of special relativistic problems of linear acceleration.
Exact Relativistic `Antigravity' Propulsion
Felber, Franklin S.
2006-01-01
The Schwarzschild solution is used to find the exact relativistic motion of a payload in the gravitational field of a mass moving with constant velocity. At radial approach or recession speeds faster than 3-1/2 times the speed of light, even a small mass gravitationally repels a payload. At relativistic speeds, a suitable mass can quickly propel a heavy payload from rest nearly to the speed of light with negligible stresses on the payload.
International Nuclear Information System (INIS)
Strange, P.
2010-01-01
Quantum revivals are now a well-known phenomena within nonrelativistic quantum theory. In this Letter we display the effects of relativity on revivals and quantum carpets. It is generally believed that revivals do not occur within a relativistic regime. Here we show that while this is generally true, it is possible, in principle, to set up wave packets with specific mathematical properties that do exhibit exact revivals within a fully relativistic theory.
Relativistic viscoelastic fluid mechanics
International Nuclear Information System (INIS)
Fukuma, Masafumi; Sakatani, Yuho
2011-01-01
A detailed study is carried out for the relativistic theory of viscoelasticity which was recently constructed on the basis of Onsager's linear nonequilibrium thermodynamics. After rederiving the theory using a local argument with the entropy current, we show that this theory universally reduces to the standard relativistic Navier-Stokes fluid mechanics in the long time limit. Since effects of elasticity are taken into account, the dynamics at short time scales is modified from that given by the Navier-Stokes equations, so that acausal problems intrinsic to relativistic Navier-Stokes fluids are significantly remedied. We in particular show that the wave equations for the propagation of disturbance around a hydrostatic equilibrium in Minkowski space-time become symmetric hyperbolic for some range of parameters, so that the model is free of acausality problems. This observation suggests that the relativistic viscoelastic model with such parameters can be regarded as a causal completion of relativistic Navier-Stokes fluid mechanics. By adjusting parameters to various values, this theory can treat a wide variety of materials including elastic materials, Maxwell materials, Kelvin-Voigt materials, and (a nonlinearly generalized version of) simplified Israel-Stewart fluids, and thus we expect the theory to be the most universal description of single-component relativistic continuum materials. We also show that the presence of strains and the corresponding change in temperature are naturally unified through the Tolman law in a generally covariant description of continuum mechanics.
Relativistic viscoelastic fluid mechanics.
Fukuma, Masafumi; Sakatani, Yuho
2011-08-01
A detailed study is carried out for the relativistic theory of viscoelasticity which was recently constructed on the basis of Onsager's linear nonequilibrium thermodynamics. After rederiving the theory using a local argument with the entropy current, we show that this theory universally reduces to the standard relativistic Navier-Stokes fluid mechanics in the long time limit. Since effects of elasticity are taken into account, the dynamics at short time scales is modified from that given by the Navier-Stokes equations, so that acausal problems intrinsic to relativistic Navier-Stokes fluids are significantly remedied. We in particular show that the wave equations for the propagation of disturbance around a hydrostatic equilibrium in Minkowski space-time become symmetric hyperbolic for some range of parameters, so that the model is free of acausality problems. This observation suggests that the relativistic viscoelastic model with such parameters can be regarded as a causal completion of relativistic Navier-Stokes fluid mechanics. By adjusting parameters to various values, this theory can treat a wide variety of materials including elastic materials, Maxwell materials, Kelvin-Voigt materials, and (a nonlinearly generalized version of) simplified Israel-Stewart fluids, and thus we expect the theory to be the most universal description of single-component relativistic continuum materials. We also show that the presence of strains and the corresponding change in temperature are naturally unified through the Tolman law in a generally covariant description of continuum mechanics.
Dissipative relativistic hydrodynamics
International Nuclear Information System (INIS)
Imshennik, V.S.; Morozov, Yu.I.
1989-01-01
Using the comoving reference frame in the general non-inertial case, the relativistic hydrodynamics equations are derived with an account for dissipative effects in the matter. From the entropy production equation, the exact from for the dissipative tensor components is obtained. As a result, the closed system of equations of dissipative relativistic hydrodynamics is obtained in the comoving reference frame as a relativistic generalization of the known Navier-Stokes equations for Lagrange coordinates. Equations of relativistic hydrodynamics with account for dissipative effects in the matter are derived using the assocoated reference system in general non-inertial case. True form of the dissipative tensor components is obtained from entropy production equation. Closed system of equations for dissipative relativistic hydrodynamics is obtained as a result in the assocoated reference system (ARS) - relativistic generalization of well-known Navier-Stokes equations for Lagrange coordinates. Equation system, obtained in this paper for ARS, may be effectively used in numerical models of explosive processes with 10 51 erg energy releases which are characteristic for flashes of supernovae, if white dwarf type compact target suggested as presupernova
International Nuclear Information System (INIS)
Arnold, Werner
2002-01-01
Contrary to natural fragmentation, controlled fragmentation offers the possibility to adapt fragment parameters like size and mass to the performance requirements in a very flexible way. Known mechanisms like grooves inside the casing, weaken the structure. This is, however, excluded for applications with high accelerations during launch or piercing requirements for example on a semi armor piercing penetrator. Another method to achieve controlled fragmentation with an additional grid layer is presented with which the required grooves are produced 'just in time' inside the casing during detonation of the high explosive. The process of generating the grooves aided by the grid layer was studied using the hydrocode HULL with respect to varying grid designs and material combinations. Subsequent to this, a large range of these theoretically investigated combinations was contemplated in substantial experimental tests. With an optimised grid design and a suitable material selection, the controlled fragment admits a very flexible adaptation to the set requirements. Additional advantages like the increase of perforation performance or incendiary amplification can be realized with the grid layer
Energy Technology Data Exchange (ETDEWEB)
Brax, Philippe [Institut de Physique Théorique, CEA, IPhT, CNRS, URA 2306, F-91191Gif/Yvette Cedex (France); Upadhye, Amol, E-mail: philippe.brax@cea.fr, E-mail: aupadhye@anl.gov [Institute for the Early Universe, Ewha University, International Education, Building #601, 11-1, Daehyun-Dong Seodaemun-Gu, Seoul 120-750 (Korea, Republic of)
2014-02-01
A scalar field dark energy candidate could couple to ordinary matter and photons, enabling its detection in laboratory experiments. Here we study the quantum properties of the chameleon field, one such dark energy candidate, in an ''afterglow'' experiment designed to produce, trap, and detect chameleon particles. In particular, we investigate the possible fragmentation of a beam of chameleon particles into multiple particle states due to the highly non-linear interaction terms in the chameleon Lagrangian. Fragmentation could weaken the constraints of an afterglow experiment by reducing the energy of the regenerated photons, but this energy reduction also provides a unique signature which could be detected by a properly-designed experiment. We show that constraints from the CHASE experiment are essentially unaffected by fragmentation for φ{sup 4} and 1/φ potentials, but are weakened for steeper potentials, and we discuss possible future afterglow experiments.
International Nuclear Information System (INIS)
Brax, Philippe; Upadhye, Amol
2014-01-01
A scalar field dark energy candidate could couple to ordinary matter and photons, enabling its detection in laboratory experiments. Here we study the quantum properties of the chameleon field, one such dark energy candidate, in an ''afterglow'' experiment designed to produce, trap, and detect chameleon particles. In particular, we investigate the possible fragmentation of a beam of chameleon particles into multiple particle states due to the highly non-linear interaction terms in the chameleon Lagrangian. Fragmentation could weaken the constraints of an afterglow experiment by reducing the energy of the regenerated photons, but this energy reduction also provides a unique signature which could be detected by a properly-designed experiment. We show that constraints from the CHASE experiment are essentially unaffected by fragmentation for φ 4 and 1/φ potentials, but are weakened for steeper potentials, and we discuss possible future afterglow experiments
Alver, B.; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Chai, Z.; Chetluru, V.; Decowski, M. P.; García, E.; Gburek, T.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Harnarine, I.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Li, W.; Lin, W. T.; Loizides, C.; Manly, S.; McLeod, D.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Richardson, E.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Sedykh, I.; Skulski, W.; Smith, C. E.; Stankiewicz, M. A.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Szostak, A.; Tang, J.-L.; Tonjes, M. B.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Walters, P.; Wenger, E.; Willhelm, D.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wyngaardt, S.; Wysłouch, B.; Phobos Collaboration
2016-08-01
Spectator fragments resulting from relativistic heavy ion collisions, consisting of single protons and neutrons along with groups of stable nuclear fragments up to nitrogen (Z =7 ), are measured in PHOBOS. These fragments are observed in Au+Au (√{sNN}=19.6 GeV ) and Cu+Cu (22.4 GeV) collisions at high pseudorapidity (η ). The dominant multiply-charged fragment is the tightly bound helium (α ), with lithium, beryllium, and boron all clearly seen as a function of collision centrality and pseudorapidity. We observe that in Cu+Cu collisions, it becomes much more favorable for the α fragments to be released than lithium. The yields of fragments approximately scale with the number of spectator nucleons, independent of the colliding ion. The shapes of the pseudorapidity distributions of fragments indicate that the average deflection of the fragments away from the beam direction increases for more central collisions. A detailed comparison of the shapes for α and lithium fragments indicates that the centrality dependence of the deflections favors a scaling with the number of participants in the collision.
DEFF Research Database (Denmark)
Kruse Aagaard, Anders
2017-01-01
The PhD project Bespoke Fragments is investigating the space emerging in the exploration of the relationship between digital drawing and fabrication, and the field of materials and their properties and capacities. Through a series of different experiments, the project situates itself in a shuttli...
Energy Technology Data Exchange (ETDEWEB)
Brown, W.S.; Green, S.J.; Hakala, W.W.; Hustrulid, W.A.; Maurer, W.C. (eds.)
1976-01-01
Experts in rock mechanics, mining, excavation, drilling, tunneling and use of underground space met to discuss the relative merits of a wide variety of rock fragmentation schemes. Information is presented on novel rock fracturing techniques; tunneling using electron beams, thermocorer, electric spark drills, water jets, and diamond drills; and rock fracturing research needs for mining and underground construction. (LCL)
A model for projectile fragmentation
International Nuclear Information System (INIS)
Chaudhuri, G; Mallik, S; Gupta, S Das
2013-01-01
A model for projectile fragmentation is developed whose origin can be traced back to the Bevalac era. The model positions itself between the phenomenological EPAX parametrization and transport models like 'Heavy Ion Phase Space Exploration' (HIPSE) model and antisymmetrised molecular dynamics (AMD) model. A very simple impact parameter dependence of input temperature is incorporated in the model which helps to analyze the more peripheral collisions. The model is applied to calculate the charge, isotopic distributions, average number of intermediate mass fragments and the average size of largest cluster at different Z bound of different projectile fragmentation reactions at different energies.
Ohm's law in the fast lane: general relatiivistic charge dynamics
Meier, D.
2004-01-01
Fully relativistic and causal equations for the flow of charge in curved spacetime are derived. It is believed that this is the first set of equations to be published that correctly describes the flow of charge, as well as the evolution of the electromagnetic field, in highly dynamical relativistic environments on timescales much shorter than the collapse time (GM/c3).
Relativistic and non-relativistic studies of nuclear matter
Banerjee, MK; Tjon, JA
2002-01-01
We point out that the differences between the results of the non-relativistic lowest order Brueckner theory (LOBT) and the relativistic Dirac-Brueckner analysis predominantly arise from two sources. Besides effects from a nucleon mass modification M* in nuclear medium we have in a relativistic
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....
International Nuclear Information System (INIS)
Trubnikov, S.V.
1984-01-01
The relativistic rotation of nucleon spin in addition to deuteron spin leads to the appearance of the new term in the deuteron charge form factor (DCFF). This term is absent in the traditional approaches and essentially influences the asymptotic behaviour of DCFF. General formulae are obtained for the DCFF asymptotics in the relativistic and nonrelativistic impulse approximation
Relativistic quantum mechanics
International Nuclear Information System (INIS)
Ollitrault, J.Y.
1998-12-01
These notes form an introduction to relativistic quantum mechanics. The mathematical formalism has been reduced to the minimum in order to enable the reader to calculate elementary physical processes. The second quantification and the field theory are the logical followings of this course. The reader is expected to know analytical mechanics (Lagrangian and Hamiltonian), non-relativistic quantum mechanics and some basis of restricted relativity. The purpose of the first 3 chapters is to define the quantum mechanics framework for already known notions about rotation transformations, wave propagation and restricted theory of relativity. The next 3 chapters are devoted to the application of relativistic quantum mechanics to a particle with 0,1/5 and 1 spin value. The last chapter deals with the processes involving several particles, these processes require field theory framework to be thoroughly described. (A.C.)
Relativistic solitons and pulsars
Energy Technology Data Exchange (ETDEWEB)
Karpman, V I [Inst. of Terrestrial Magnetism, Ionosphere, and Radio-Wave Propagation, Moscow; Norman, C A; ter Haar, D; Tsytovich, V N
1975-05-01
A production mechanism for stable electron bunches or sheets of localized electric fields is investigated which may account for pulsar radio emission. Possible soliton phenomena in a one-dimensional relativistic plasma are analyzed, and it is suggested that the motion of a relativistic soliton, or ''relaton'', along a curved magnetic-field line may produce radio emission with the correct polarization properties. A general MHD solution is obtained for relatons, the radiation produced by a relativistic particle colliding with a soliton is evaluated, and the emission by a soliton moving along a curved field line is estimated. It is noted that due to a number of severe physical restrictions, curvature radiation is not a very likely solution to the problem of pulsar radio emission. (IAA)
Relativistic quantum mechanics
Horwitz, Lawrence P
2015-01-01
This book describes a relativistic quantum theory developed by the author starting from the E.C.G. Stueckelberg approach proposed in the early 40s. In this framework a universal invariant evolution parameter (corresponding to the time originally postulated by Newton) is introduced to describe dynamical evolution. This theory is able to provide solutions for some of the fundamental problems encountered in early attempts to construct a relativistic quantum theory. A relativistically covariant construction is given for which particle spins and angular momenta can be combined through the usual rotation group Clebsch-Gordan coefficients. Solutions are defined for both the classical and quantum two body bound state and scattering problems. The recently developed quantum Lax-Phillips theory of semigroup evolution of resonant states is described. The experiment of Lindner and coworkers on interference in time is discussed showing how the property of coherence in time provides a simple understanding of the results. Th...
Relativistic theories of materials
Bressan, Aldo
1978-01-01
The theory of relativity was created in 1905 to solve a problem concerning electromagnetic fields. That solution was reached by means of profound changes in fundamental concepts and ideas that considerably affected the whole of physics. Moreover, when Einstein took gravitation into account, he was forced to develop radical changes also in our space-time concepts (1916). Relativistic works on heat, thermodynamics, and elasticity appeared as early as 1911. However, general theories having a thermodynamic basis, including heat conduction and constitutive equations, did not appear in general relativity until about 1955 for fluids and appeared only after 1960 for elastic or more general finitely deformed materials. These theories dealt with materials with memory, and in this connection some relativistic versions of the principle of material indifference were considered. Even more recently, relativistic theories incorporating finite deformations for polarizable and magnetizable materials and those in which couple s...
Handbook of relativistic quantum chemistry
International Nuclear Information System (INIS)
Liu, Wenjian
2017-01-01
This handbook focuses on the foundations of relativistic quantum mechanics and addresses a number of fundamental issues never covered before in a book. For instance: How can many-body theory be combined with quantum electrodynamics? How can quantum electrodynamics be interfaced with relativistic quantum chemistry? What is the most appropriate relativistic many-electron Hamiltonian? How can we achieve relativistic explicit correlation? How can we formulate relativistic properties? - just to name a few. Since relativistic quantum chemistry is an integral component of computational chemistry, this handbook also supplements the ''Handbook of Computational Chemistry''. Generally speaking, it aims to establish the 'big picture' of relativistic molecular quantum mechanics as the union of quantum electrodynamics and relativistic quantum chemistry. Accordingly, it provides an accessible introduction for readers new to the field, presents advanced methodologies for experts, and discusses possible future perspectives, helping readers understand when/how to apply/develop the methodologies.
Handbook of relativistic quantum chemistry
Energy Technology Data Exchange (ETDEWEB)
Liu, Wenjian (ed.) [Peking Univ., Beijing (China). Center for Computational Science and Engineering
2017-03-01
This handbook focuses on the foundations of relativistic quantum mechanics and addresses a number of fundamental issues never covered before in a book. For instance: How can many-body theory be combined with quantum electrodynamics? How can quantum electrodynamics be interfaced with relativistic quantum chemistry? What is the most appropriate relativistic many-electron Hamiltonian? How can we achieve relativistic explicit correlation? How can we formulate relativistic properties? - just to name a few. Since relativistic quantum chemistry is an integral component of computational chemistry, this handbook also supplements the ''Handbook of Computational Chemistry''. Generally speaking, it aims to establish the 'big picture' of relativistic molecular quantum mechanics as the union of quantum electrodynamics and relativistic quantum chemistry. Accordingly, it provides an accessible introduction for readers new to the field, presents advanced methodologies for experts, and discusses possible future perspectives, helping readers understand when/how to apply/develop the methodologies.
Energy Technology Data Exchange (ETDEWEB)
Konecny, E.; Opower, H.; Guenther, H.; Goebel, H. [Physik-Department der Technischen Hochschule Muenchen, Munich and II. Physikalisches Institut der Justus Liebig-Universitaet Giessen, Federal Republic of Germany (Germany)
1965-07-15
By a mass spectrometer fission fragments from thermal fission of U{sup 235} are exactly separated with respect to mass and kinetic energy within a time of 10{sup -6} s after fission. The separated fragments are caught in a {beta}-sensitive Ilford G 5 emulsion that is located in the focal plane of the spectrometer. Development of the irradiated emulsions is carried out, if possible, after a time long compared with the longest half-life of the regarded decay chain. Half-lives of days or longer are not taken into account, but corrections can be easily made for them. After development of the emulsions all beta tracks emerging from the end of every fission-fragment track can be seen under the microscope. The possibility of correlating every single {beta}-track with a particular fission-fragment track allows the evaluation of the number n(x) of fission fragments possessing x {beta}-tracks, thus giving not only the mean chain length but also the {beta}-particle distribution. As the stable end product of each decay chain is known, this {beta}-distribution is an exact image of the primary nuclear charge distribution. In the measurements done up to now only {beta}-particles emitted into the half solid angle formed by the emulsion plate were registered, buta simple statistical calculation enables the desired 4{pi}-distribution to be evaluated. By this method {beta}-distributions at fixed kinetic energies near the mean kinetic energy of each fragment mass are given for the masses 132, 134, 136 and 137. For the lower masses 132 and 134 the neutron shell N = 82 is responsible for the most probable primary charges near 50 and 52 respectively. For M = 136 and 137 the primary charge is about 53 and 53.2. Additional approximative corrections in respect of conversion electrons (by omitting very short {beta}-tracks corresponding to very low {beta}-energies) and to delayed neutrons (for mass 137) were not very large. Similar measurements carried out directly in 4{pi}-geometry to avoid
Biquaternions and relativistic kinematics
International Nuclear Information System (INIS)
Bogush, A.A.; Kurochkin, Yu.A.; Fedorov, F.I.
1979-01-01
The problems concerning the use of quaternion interpretation of the Lorentz group vector parametrization are considered for solving relativistic kinematics problems. A vector theory convenient for describing the characteristic features of the Lobachevsky space is suggested. The kinematics of elementary particle scattering is investigated on the basis of this theory. A synthesis of vector parametrization and of quaternion calculation has been shown to lead to natural formulation of the theory of vectors in the three-dimensional Lobachevsky space, realized on mass hyperboloids of relativistic particles
Relativistic heavy ion collisions
International Nuclear Information System (INIS)
Barz, H.W.; Kaempfer, B.; Schulz, H.
1984-12-01
An elementary introduction is given into the scenario of relativistic heavy ion collisions. It deals with relativistic kinematics and estimates of energy densities, extrapolations of the present knowledge of hadron-hadron and hadron-nuleus to nucleus-nucleus collisions, the properties of the quark-gluon plasma and the formation of the plasma and possible experimental signatures. Comments are made on a cosmic ray experiment which could be interpreted as a first indication of the quark-gluon phase of the matter. (author)
Energy Technology Data Exchange (ETDEWEB)
Gavrilov, S.P. [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil); Gitman, D.M. [Sao Paulo Univ. (USP), SP (Brazil). Inst. de Fisica
2000-07-01
Full text follows: There is a common opinion that the construction of a consistent relativistic quantum mechanics on the base of a relativistic wave equation meets well-known difficulties related to the existence of infinite number of negative energy levels, to the existence of negative vector norms, and so on, which may be only solved in a second-quantized theory, see, for example, two basic papers devoted to the problem L.Foldy, S.Wouthuysen, Phys. Rep.78 (1950) 29; H.Feshbach, F.Villars, Rev. Mod. Phys. 30 (1958) 24, whose arguments are repeated in all handbooks in relativistic quantum theory. Even Dirac trying to solve the problem had turned last years to infinite-component relativistic wave equations, see P.A.M. Dirac, Proc. R. Soc. London, A328 (1972) 1. We believe that a consistent relativistic quantum mechanics may be constructed on the base of an extended (charge symmetric) equation, which unite both a relativistic wave equation for a particle and for an antiparticle. We present explicitly the corresponding construction, see for details hep-th/0003112. We support such a construction by two demonstrations: first, in course of a careful canonical quantization of the corresponding classical action of a relativistic particle we arrive just to such a consistent quantum mechanics; second, we demonstrate that a reduction of the QFT of a corresponding field (scalar, spinor, etc.) to one-particle sector, if such a reduction may be done, present namely this quantum mechanics. (author)
DEFF Research Database (Denmark)
Bang, Jacob Sebastian
2018-01-01
I have created a large collection of plaster models: a collection of Obstructions, errors and opportunities that may develop into architecture. The models are fragments of different complex shapes as well as more simple circular models with different profiling and diameters. In this contect I have....... I try to invent the ways of drawing the models - that decode and unfold them into architectural fragments- into future buildings or constructions in the landscape. [1] Luigi Moretti: Italian architect, 1907 - 1973 [2] Man Ray: American artist, 1890 - 1976. in 2015, I saw the wonderful exhibition...... "Man Ray - Human Equations" at the Glyptotek in Copenhagen, organized by the Philips Collection in Washington D.C. and the Israel Museum in Jerusalem (in 2013). See also: "Man Ray - Human Equations" catalogue published by Hatje Cantz Verlag, Germany, 2014....
Relativistic particle in a box
Alberto, P.; Fiolhais, Carlos; Gil, Victor
1996-01-01
The problem of a relativistic spin 1/2 particle confined to a one-dimensional box is solved in a way that resembles closely the solution of the well known quantum-mechanical textbook problem of a non-relativistic particle in a box. The energy levels and probability density are computed and compared with the non-relativistic case
A Hamilton-like vector for the special-relativistic Coulomb problem
International Nuclear Information System (INIS)
Munoz, Gerardo; Pavic, Ivana
2006-01-01
A relativistic point charge moving in a Coulomb potential does not admit a conserved Hamilton vector. Despite this fact, a Hamilton-like vector may be developed that proves useful in the derivation and analysis of the particle's orbit
Intriguing aspects in baryon production at relativistic heavy-ion collider
Indian Academy of Sciences (India)
The commencement of the relativistic heavy ion collider (RHIC) operation at Brookhaven ... that an unprecedented high-energy density has been achieved in ... for charged particles and measurement of ionization energy loss (dE/dx) for limited ...
Non-relativistic supersymmetry
International Nuclear Information System (INIS)
Clark, T.E.; Love, S.T.
1984-01-01
The most general one- and two-body hamiltonian invariant under galilean supersymmetry is constructed in superspace. The corresponding Feynman rules are given for the superfield Green functions. As demonstrated by a simple example, it is straightforward to construct models in which the supersymmetry is spontaneously broken by the non-relativistic vacuum. (orig.)
International Nuclear Information System (INIS)
Contopoulos, G.
1983-01-01
In this paper, three main areas of relativistic stellar dynamics are reviewed: (a) The dynamics of clusters, or nuclei of galaxies, of very high density; (b) The dynamics of systems containing a massive black hole; and (c) The dynamics of particles (and photons) in an expanding Universe. The emphasis is on the use of orbit perturbations. (Auth.)
Directory of Open Access Journals (Sweden)
Bialynicki-Birula Iwo
2014-01-01
Full Text Available Original definition of the Wigner function can be extended in a natural manner to relativistic domain in the framework of quantum field theory. Three such generalizations are described. They cover the cases of the Dirac particles, the photon, and the full electromagnetic field.
Antippa, Adel F.
2009-01-01
We solve the problem of the relativistic rocket by making use of the relation between Lorentzian and Galilean velocities, as well as the laws of superposition of successive collinear Lorentz boosts in the limit of infinitesimal boosts. The solution is conceptually simple, and technically straightforward, and provides an example of a powerful…
Relativistic few body calculations
International Nuclear Information System (INIS)
Gross, F.
1988-01-01
A modern treatment of the nuclear few-body problem must take into account both the quark structure of baryons and mesons, which should be important at short range, and the relativistic exchange of mesons, which describes the long range, peripheral interactions. A way to model both of these aspects is described. The long range, peripheral interactions are calculated using the spectator model, a general approach in which the spectators to nucleon interactions are put on their mass-shell. Recent numerical results for a relativistic OBE model of the NN interaction, obtained by solving a relativistic equation with one-particle on mass-shell, will be presented and discussed. Two meson exchange models, one with only four mesons (π,σ,/rho/,ω) but with a 25% admixture of γ 5 coupling for the pion, and a second with six mesons (π,σ,/rho/,ω,δ,/eta/) but pure γ 5 γ/sup μ/ pion coupling, are shown to give very good quantitative fits to the NN scattering phase shifts below 400 MeV, and also a good description of the /rvec p/ 40 Ca elastic scattering observables. Applications of this model to electromagnetic interactions of the two body system, with emphasis on the determination of relativistic current operators consistent with the dynamics and the exact treatment of current conservation in the presence of phenomenological form factors, will be described. 18 refs., 8 figs
Relativistic Polarizable Embedding
DEFF Research Database (Denmark)
Hedegård, Erik Donovan; Bast, Radovan; Kongsted, Jacob
2017-01-01
Most chemistry, including chemistry where relativistic effects are important, occurs in an environment, and in many cases, this environment has a significant effect on the chemistry. In nonrelativistic quantum chemistry, a lot of progress has been achieved with respect to including environments s...
Relativistic length agony continued
Directory of Open Access Journals (Sweden)
Redžić D.V.
2014-01-01
Full Text Available We made an attempt to remedy recent confusing treatments of some basic relativistic concepts and results. Following the argument presented in an earlier paper (Redžić 2008b, we discussed the misconceptions that are recurrent points in the literature devoted to teaching relativity such as: there is no change in the object in Special Relativity, illusory character of relativistic length contraction, stresses and strains induced by Lorentz contraction, and related issues. We gave several examples of the traps of everyday language that lurk in Special Relativity. To remove a possible conceptual and terminological muddle, we made a distinction between the relativistic length reduction and relativistic FitzGerald-Lorentz contraction, corresponding to a passive and an active aspect of length contraction, respectively; we pointed out that both aspects have fundamental dynamical contents. As an illustration of our considerations, we discussed briefly the Dewan-Beran-Bell spaceship paradox and the ‘pole in a barn’ paradox. [Projekat Ministarstva nauke Republike Srbije, br. 171028
Relativistic Coulomb excitation
International Nuclear Information System (INIS)
Winther, A.; Alder, K.
1979-01-01
Coulomb excitation of both target and projectile in relativistic heavy ion collisions is evaluated including the lowest order correction for the deviation from a straight line trajectory. Explicit results for differential and total cross sections are given in the form of tables and figures. (Auth.)
Fundamental Relativistic Rotator
International Nuclear Information System (INIS)
Staruszkiewicz, A.
2008-01-01
Professor Jan Weyssenhoff was Myron Mathisson's sponsor and collaborator. He introduced a class of objects known in Cracow as '' kreciolki Weyssenhoffa '', '' Weyssenhoff's rotating little beasts ''. The Author describes a particularly simple object from this class. The relativistic rotator described in the paper is such that its both Casimir invariants are parameters rather than constants of motion. (author)
Cosmic gamma-ray burst from intergalactic relativistic dust grains
International Nuclear Information System (INIS)
Dasgupta, A.K.
1979-01-01
Charged dust grains of radii a approximately 3 x 10 -6 approximately 3 x 10 -5 cm may acquire relativistic energy (>10 18 eV) in the intergalactic medium. In order to attain relativistic energy, dust grains have to move in and out ('scattering') of the magnetic field of the medium. A relativistic grain of radius a -5 cm with Lorentz factor γ approximately 10 3 approaching the Earth will break up either due to electrostatic charge or due to sputtering about 150 approximately 100 km, and may scatter solar photons via a fluorescence process. Dust grains may also melt into droplets in the solar vicinity and may contribute towards observed gamma-ray bursts. (Auth.)
Relativistic Quantum Mechanics
International Nuclear Information System (INIS)
Antoine, J-P
2004-01-01
The aim of relativistic quantum mechanics is to describe the finer details of the structure of atoms and molecules, where relativistic effects become nonnegligible. It is a sort of intermediate realm, between the familiar nonrelativistic quantum mechanics and fully relativistic quantum field theory, and thus it lacks the simplicity and elegance of both. Yet it is a necessary tool, mostly for quantum chemists. Pilkuhn's book offers to this audience an up-to-date survey of these methods, which is quite welcome since most previous textbooks are at least ten years old. The point of view of the author is to start immediately in the relativistic domain, following the lead of Maxwell's equations rather than classical mechanics, and thus to treat the nonrelativistic version as an approximation. Thus Chapter 1 takes off from Maxwell's equations (in the noncovariant Coulomb gauge) and gradually derives the basic aspects of Quantum Mechanics in a rather pedestrian way (states and observables, Hilbert space, operators, quantum measurement, scattering,. Chapter 2 starts with the Lorentz transformations, then continues with the Pauli spin equation and the Dirac equation and some of their applications (notably the hydrogen atom). Chapter 3 is entitled 'Quantum fields and particles', but falls short of treating quantum field theory properly: only creation/annihilation operators are considered, for a particle in a box. The emphasis is on two-electron states (the Pauli principle, the Foldy--Wouthuysen elimination of small components of Dirac spinors, Breit projection operators. Chapter 4 is devoted to scattering theory and the description of relativistic bound states. Chapter 5, finally, covers hyperfine interactions and radiative corrections. As we said above, relativistic quantum mechanics is by nature limited in scope and rather inelegant and Pilkuhn's book is no exception. The notation is often heavy (mostly noncovariant) and the mathematical level rather low. The central topic
New results with stored exotic nuclei at relativistic energies
Energy Technology Data Exchange (ETDEWEB)
Bosch, F. (Fritz); Boutin, D. (Daniel); Fastermann, T. (Thomas); Falch, M. (Markus); Franzke, B. (Bernhard); Hausmann, M. (Marc); Hellstrom, M. (Margarete); Kaza, E. (Evangelia); Kerscher, T. (Thomas); Klepper, O. (Otto); Kluge, H.-Jürgen; Kozhuharov, C. (Christophor); Kratz, K. L.; Litinov, S. A. (Sergei A); Lobner, G. K. E. (Gunther K. E.); Maier, L. (Ludwig); Matos, M. (Milan); Munzenberg, G. (Gottfried); Nolden, F. (Fritz); Novikov, Y. N. (Yuri N.); Ohtsubo, T. (Takashi); Ostrowski, A. (Alexander); Patyk, Z. (Zygmund); Pfeiffer, B.; Portillo, M. (Mauricio); Radon, T. P. (Torsten P.); Scheidenberger, C. (Christoph); Shishkin, V. (Vladimir); Stadlman, J. (Jens); Steck, M. (Markus); Vieira, D. J. (David J.); Weick, H. (Helmut); Winkler, M. (Martin); Wollnik, Hermann; Yamaguchi, T. (Takayuki)
2004-01-01
Recently, much progress has been made with stored exotic nuclei at relativistic velocities v/c = 0.7. Fragments of {sup 208}Pb and {sup 209}Bi projectiles and fission fragments from {sup 238}U ions have been produced, separated in flight with the fragment separator FRS, and injected into the storage-cooler ring ESR for precision measurements. Precise masses of neutron-deficient isotopes in the lead region have been measured with time-resolved Schottky Mass Spectrometry (SMS). A new isospin dependence of the pairing energy was observed due to the improved mass accuracy of typical 1.5 x 10{sup -7} (30 keV). New masses of short-lived neutron-rich fission fragments have been obtained with Isochronous Mass Spectrometry (IMS). An innovative field of spectroscopy has been opened up with lifetime measurements of stored bare and few-electron fragments after applying both stochastic and electron cooling.
Nuclear fragmentation by nucleation approach
International Nuclear Information System (INIS)
Chung, K.C.
1992-01-01
The nucleation model is used to simulate nuclear fragmentation processes. The critical value of the effective interaction radius is shown to vary linearly with the expansion factor α. The calculated mass and charge distributions are compared with some experimental data. (author)
International Nuclear Information System (INIS)
Hojsik, M.; Gmuca, S.
1998-01-01
Relativistic microscopic calculations are presented for proton elastic scattering from 40 Ca at 500 MeV. The underlying target densities are calculated within the framework of the relativistic mean-field theory with several parameter sets commonly in use. The self consistency of the scalar and vector densities (and thus to relativistic mean-field parameters) is investigated. Recently, the relativistic impulse approximation (RIA) has been widely and repeatedly used for the calculations of proton-nucleus scattering at intermediate energies. These calculations have exhibited significant improvements over the nonrelativistic approaches. The relativistic impulse approximation calculations. in particular, provide a dramatically better description of the spin observables, namely the analyzing power, A y , and the spin-rotation function, Q, at least for energies higher than 400 MeV. In the relativistic impulse approximation, the Dirac optical potential is obtained by folding of the local Lorentz-invariant amplitudes with the corresponding nuclear densities. For the spin zero targets the scalar and vector terms give the dominant contributions. Thus the scalar and vector nuclear densities (both, proton and neutron ones) play the dominant role in the relativistic impulse approximation. While the proton vector densities can be obtained by unfolding from the empirically known charge densities, all other densities used rely to a great extent on theoretical models. The various recipes are used to construct the neutron vector densities and the scalar densities for both, neutrons and protons. In this paper we will study the sensitivity of the relativistic impulse approximation results on the various sets of relativistic mean-field parameters currently in use
Cherenkov particle identifier for relativistic heavy ions
Energy Technology Data Exchange (ETDEWEB)
Dufour, J P; Olson, D L; Baumgartner, M; Girard, J G; Lindstrom, P J; Greiner, D E; Symons, T J.M.; Crawford, H J
1985-12-01
A total internal reflection Cherenkov detector is described. A figure of merit of 84Z/sup 2/sin/sup 2/theta photoelectrons/cm has been measured and the application of the device to charge and velocity measurements of relativistic heavy ions has been tested. We have achieved a charge resolution of ..delta..Zsub(rms)=0.15e for Z=20 with a 3 mm thick glass detector and a velocity resolution of ..delta beta..sub(rms)=2x10/sup -4/ at ..beta..=0.93 and Z=26 with a 6 mm thick fused silica detector. Combining charge and velocity measurements with a magnetic rigidity selection, we have achieved an isotopic mass resolution of ..delta..Msub(rms)=0.1 u with a 2 mm thick fused silica detector for 20
Cherenkov particle identifier for relativistic heavy ions
Energy Technology Data Exchange (ETDEWEB)
Dufour, J P; Olson, D L; Baumgartner, M; Girard, J G; Lindstrom, P J; Greiner, D E; Symons, T J.M.; Crawford, H J
1985-12-01
A total internal reflection Cherenkov detector is described. A figure of merit of 84Z/sup 2/sin/sup 2/theta photoelectrons/cm has been measured and the application of the device to charge and velocity measurements of relativistic heavy ions has been tested. We have achieved a charge resolution of ..delta..Zsub(rms)=0.15e for Z=20 with a 3 mm thick glass detector and a velocity resolution of ..delta beta..sub(rms)=2 x 10/sup -4/ at ..beta..=0.93 and Z=26 with a 6 mm thick fused silica detector. Combining charge and velocity measurements with a magnetic rigidity selection, we have achieved an isotopic mass resolution of ..delta..Msub(rms)=0.1 u with a 2 mm thick fused silica detector for 20 < A < 40.
DEFF Research Database (Denmark)
Kruse Aagaard, Anders
2015-01-01
This text and its connected exhibition are aiming to reflect both on the thoughts, the processes and the outcome of the design and production of the artefact ‘Intermediate Fragment’ and making as a contemporary architectural tool in general. Intermediate Fragment was made for the exhibition ‘Enga...... of realising an exhibition object was conceived, but expanded, refined and concretised through this process. The context of the work shown here is an interest in a tighter, deeper connection between experimentally obtained material knowledge and architectural design....
Directory of Open Access Journals (Sweden)
Shashank Srivastava
2014-01-01
Gaining the understanding of mobile agent architecture and the security concerns, in this paper, we proposed a security protocol which addresses security with mitigated computational cost. The protocol is a combination of self decryption, co-operation and obfuscation technique. To circumvent the risk of malicious code execution in attacking environment, we have proposed fragmentation based encryption technique. Our encryption technique suits the general mobile agent size and provides hard and thorny obfuscation increasing attacker’s challenge on the same plane providing better performance with respect to computational cost as compared to existing AES encryption.
DEFF Research Database (Denmark)
Kruse Aagaard, Anders
2016-01-01
, investigating levels of control and uncertainty encountering with these. Through tangible experiments, the project discusses materiality and digitally controlled fabrications tools as direct expansions of the architect's digital drawing and workflow. The project sees this expansion as an opportunity to connect...... architectural designs, tectonics and aesthetics. In this Ph.D.-project a series a physical, but conceptual, experiment plays the central role in the knowledge production. The experiments result in materialised architectural fragments and tangible experiences. However, these creations also become the driving...
Hydrodynamic modelling for relativistic heavy-ion collisions at RHIC ...
Indian Academy of Sciences (India)
model, to describe the microscopic evolution and decoupling of the hadronic ... progress on hydrodynamic modelling, investigation on the flow data and the ... and to describe and predict the soft particle physics in relativistic heavy-ion collisions [4]. It is based on the conservation laws of energy, momentum and net charge ...
Relativistic generalisation of the Kroll-Watson formula
International Nuclear Information System (INIS)
Kaminski, J.Z.
1985-01-01
The relativistic analogue of the space-translation method is derived. Using this method the generalisation of the Kroll-Watson formula [1973, Phys. Rev. A. 8 804] is obtained for the scattering of an arbitrary charged particle (e.g. mesons, hyperons, quarks, etc). The separation of the background and resonant parts of the scattering amplitude is predicted. (author)
Coherent polarization radiation of relativistic electrons in crystals
International Nuclear Information System (INIS)
Morokhovskii, V.L.
2014-01-01
A brief narration about the history of those heated arguments and discussions around the nature of so-called parametric X-radiation, which were concluded by the recognition of the discovery the phenomenon of coherent polarization bremsstrahlung of relativistic charged particles in crystals. Some important information and comments, which stay over of notice of specialists till now are reported.
Two-dimensional ion effects in relativistic diodes
International Nuclear Information System (INIS)
Poukey, J.W.
1975-01-01
In relativistic diodes, ions are emitted from the anode plasma. The effects and properties of these ions are studied via a two-dimensional particle simulation code. The space charge of these ions enhances the electron emission, and this additional current (including that of the ions, themselves) aids in obtaining superpinched electron beams for use in pellet fusion studies. (U.S.)
On the relativistic and nonrelativistic electron descriptions in high-energy atomic collisions
International Nuclear Information System (INIS)
Voitkiv, A.B
2007-01-01
We consider the relativistic and nonrelativistic descriptions of an atomic electron in collisions with point-like charged projectiles moving at relativistic velocities. We discuss three different forms of the fully relativistic first-order transition amplitude. Using the Schroedinger-Pauli equation to describe the atomic electron we establish the correct form of the nonrelativistic first-order transition amplitude. We also show that the so-called semi-relativistic treatment, in which the Darwin states are used to describe the atomic electron, is in fact fully equivalent to the nonrelativistic consideration. The comparison of results obtained with the relativistic and nonrelativistic electron descriptions shows that the latter is accurate within 20-30% up to Z a ∼ a is the atomic nuclear charge
Self-focusing relativistic electron streams in plasmas
International Nuclear Information System (INIS)
Cox, J.L. Jr.
1975-01-01
A relativistic electron stream propagating through a dense plasma induces current and charge densities which determine how the stream can self-focus. Magnetic self-focusing is possible because stream-current neutralization, although extensive, is not complete. Electric self-focusing can occur because the stream charge becomes overneutralized when the net current is smaller than a critical value. Under some circumstances, the latter process can cause the stream to focus into a series of electron bunches
Intermittency in 197Au fragmentation
International Nuclear Information System (INIS)
Dabrowska, A.; Holynski, R.; Olszewski, A.; Szarska, M.; Wilczynska, B.; Wolter, W.; Wosiek, B.; Cherry, M.L.; Deines-Jones, P.; Jones, W.V.; Sengupta, K.; Wefel, B.
1995-07-01
The concept of factorial moments was applied to an analysis of the dynamical fluctuations in the charge distributions of the fragments emitted from gold nuclei with energies 10.6 and < 1.0 GeV/n interacting with emulsion nuclei. Clear evidence for intermittent fluctuations has been found in an analysis using all the particles released from the gold projectile, with a stronger effect observed below 1 GeV/n than at 10.6 GeV/n. For the full data sets, however, the intermittency effect was found to be very sensitive to the singly charged particles, and neglecting these particles strongly reduces the intermittency signal. When the analysis is restricted to the multiply charged fragments, an intermittency effect is revealed only for multifragmentation events, although one that is enhanced as compared to the analysis of all, singly and multiply charged, particles. The properties of the anomalous fractal dimensions suggest a sequential decay mechanism, rather than the existence of possible critical behaviour in the process of nuclear fragmentation. The likely influence of the charge conservation effects and the finite size of decaying systems on the observed intermittency signals was pointed out. (author). 37 refs, 9 figs, 5 tabs
Fragmentation of neck-like structures
International Nuclear Information System (INIS)
Montoya, C.; Bowman, D.R.; Peaslee, G.F.; Michigan State Univ., East Lansing, MI
1994-01-01
Evidence for intermediate mass fragment emission from neck-like structures joining projectile- and target-like residues has been observed for peripheral 129 Xe+ nat Cu collisions at E/A=50 MeV. These framents are emitted primarily at velocities intermediate between those of the projectile and the target. Relative to the charge distribution for fragments evaporated from the projectile-like residue, the distribution for ''neck'' emission shows an enhanced emission for fragments with 4 f < 8. (orig.)
Production of light fragments in hA collisions at high energies
International Nuclear Information System (INIS)
Braun, M.A.; Vechernin, V.V.
1988-12-01
Production of fast relativistic light fragments in hA collisions at high energies is considered. Direct coalescence of produced nucleons into fragments is shown to be the main mechanism for fragment production. The influence of the nuclear field is small and is not described by the well-known Butler-Pearson formulas. The coalescence coefficient strongly depends on the angle and on the behaviour of the fragment wave function at small internucleon distances. (author). 14 refs, 7 figs
The relativistic gravity train
Seel, Max
2018-05-01
The gravity train that takes 42.2 min from any point A to any other point B that is connected by a straight-line tunnel through Earth has captured the imagination more than most other applications in calculus or introductory physics courses. Brachystochron and, most recently, nonlinear density solutions have been discussed. Here relativistic corrections are presented. It is discussed how the corrections affect the time to fall through Earth, the Sun, a white dwarf, a neutron star, and—the ultimate limit—the difference in time measured by a moving, a stationary and the fiducial observer at infinity if the density of the sphere approaches the density of a black hole. The relativistic gravity train can serve as a problem with approximate and exact analytic solutions and as numerical exercise in any introductory course on relativity.
Relativistic gravitational instabilities
International Nuclear Information System (INIS)
Schutz, B.F.
1987-01-01
The purpose of these lectures is to review and explain what is known about the stability of relativistic stars and black holes, with particular emphases on two instabilities which are due entirely to relativistic effects. The first of these is the post-Newtonian pulsational instability discovered independently by Chandrasekhar (1964) and Fowler (1964). This effectively ruled out the then-popular supermassive star model for quasars, and it sets a limit to the central density of white dwarfs. The second instability was also discovered by Chandrasekhar (1970): the gravitational wave induced instability. This sets an upper bound on the rotation rate of neutron stars, which is near that of the millisecond pulsar PSR 1937+214, and which is beginning to constrain the equation of state of neutron matter. 111 references, 5 figures
Relativistic studies in actinides
International Nuclear Information System (INIS)
Weinberger, P.; Gonis, A.
1987-01-01
In this review the theoretical background is given for a relativistic description for actinide systems. A short introduction is given of the density functional theory which forms the basis for a fully relativistic single-particle theory. A section on the Dirac Hamiltonian is followed by a brief summary on group theoretical concepts. Single site scattering is presented such that formal extensions to the case of the presence of an internal (external) magnetic field and/or anisotropic scattering are evident. Multiple scattering is discussed such that it can readily be applied also to the problem of dislocations. In connection with the problem of selfconsistency particular attention is drawn to the use of complex energies. Finally the various theoretical aspects discussed are illustrated through the results of numerical calculations. 101 refs.; 37 figs.; 5 tabs
DEFF Research Database (Denmark)
Bundgaard, Charlotte
2009-01-01
Contemporary industrialized architecture based on advanced information technology and highly technological production processes, implies a radically different approach to architecture than what we have experienced in the past. Works of architecture composed of prefabricated building components......, contain distinctive architectural traits, not only based on rational repetition, but also supporting composition and montage as dynamic concepts. Prefab architecture is an architecture of fragmentation, individualization and changeability, and this sets up new challenges for the architect. This paper...... tries to develop a strategy for the architect dealing with industrially based architecture; a strategy which exploits architectural potentials in industrial building, which recognizes the rules of mass production and which redefines the architect’s position among the agents of building. If recent...
Foil focusing of relativistic electron beams
Energy Technology Data Exchange (ETDEWEB)
Ekdahl, Jr., Carl August [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2017-10-26
When an intense relativistic electron beams (IREB) passes through a grounded metal foil, the transverse electric field due to the beam space charge is locally shorted out, and the beam is focused by the magnetic field of its current. The effect can be treated as focusing by a thin lens with first order aberration. Expressions for the focal length and aberration coefficient of the equivalent thin lens are developed in this note. These are then applied to practical examples representative of IREB research at Los Alamos National Laboratory.
Relativistic heavy ion reactions
Energy Technology Data Exchange (ETDEWEB)
Brink, D M
1989-08-01
The theory of quantum chromodynamics predicts that if nuclear matter is heated to a sufficiently high temperature then quarks might become deconfined and a quark-gluon plasma could be produced. One of the aims of relativistic heavy ion experiments is to search for this new state of matter. These lectures survey some of the new experimental results and give an introduction to the theories used to interpret them. 48 refs., 4 tabs., 11 figs.
Bratek, Łukasz
2015-01-01
Two particularly simple ideal clocks exhibiting intrinsic circular motion with the speed of light and opposite spin alignment are described. The clocks are singled out by singularities of an inverse Legendre transformation for relativistic rotators of which mass and spin are fixed parameters. Such clocks work always the same way, no matter how they move. When subject to high accelerations or falling in strong gravitational fields of black holes, the clocks could be used to test the clock hypo...
Relativistic heavy ion reactions
International Nuclear Information System (INIS)
Brink, D.M.
1989-08-01
The theory of quantum chromodynamics predicts that if nuclear matter is heated to a sufficiently high temperature then quarks might become deconfined and a quark-gluon plasma could be produced. One of the aims of relativistic heavy ion experiments is to search for this new state of matter. These lectures survey some of the new experimental results and give an introduction to the theories used to interpret them. 48 refs., 4 tabs., 11 figs
Gravitationally confined relativistic neutrinos
Vayenas, C. G.; Fokas, A. S.; Grigoriou, D.
2017-09-01
Combining special relativity, the equivalence principle, and Newton’s universal gravitational law with gravitational rather than rest masses, one finds that gravitational interactions between relativistic neutrinos with kinetic energies above 50 MeV are very strong and can lead to the formation of gravitationally confined composite structures with the mass and other properties of hadrons. One may model such structures by considering three neutrinos moving symmetrically on a circular orbit under the influence of their gravitational attraction, and by assuming quantization of their angular momentum, as in the Bohr model of the H atom. The model contains no adjustable parameters and its solution, using a neutrino rest mass of 0.05 eV/c2, leads to composite state radii close to 1 fm and composite state masses close to 1 GeV/c2. Similar models of relativistic rotating electron - neutrino pairs give a mass of 81 GeV/c2, close to that of W bosons. This novel mechanism of generating mass suggests that the Higgs mass generation mechanism can be modeled as a latent gravitational field which gets activated by relativistic neutrinos.
Point form relativistic quantum mechanics and relativistic SU(6)
Klink, W. H.
1993-01-01
The point form is used as a framework for formulating a relativistic quantum mechanics, with the mass operator carrying the interactions of underlying constituents. A symplectic Lie algebra of mass operators is introduced from which a relativistic harmonic oscillator mass operator is formed. Mass splittings within the degenerate harmonic oscillator levels arise from relativistically invariant spin-spin, spin-orbit, and tensor mass operators. Internal flavor (and color) symmetries are introduced which make it possible to formulate a relativistic SU(6) model of baryons (and mesons). Careful attention is paid to the permutation symmetry properties of the hadronic wave functions, which are written as polynomials in Bargmann spaces.
On the relativistic calculation of spontaneous emission
International Nuclear Information System (INIS)
Boudet, R.
1993-01-01
In a recent work, Barut and Salamin (1988) have derived a method for calculating the relativistic decay rates in atoms, in a formulation of quantum electrodynamics based upon the electron's self-energy. The decay rate appears as the imaginary part of a formula giving a complex energy shift, the real part of the formula being the Lamb shift. The presence of the the decay rate in the imaginary part of a formula, giving an energy in its real part, may appear a bit strange. A confirmation of the Barut and Alamin calculation, by means of a quite different point of view, would be useful. Therefore in this work the Einstein A coefficients are calculated, in all cases of degeneracies of the Dirac transition currents, by means of the energy balance method. This point of view is based on the balance between the energy released during the transitions of electrons from a higher state to a lower one, and the flux of the Poynting vector of the classical electromagnetic field, created by the electrons, through a sphere a large radius. The particularity of the present work lies in the direct calculation of the relativistic Dirac transition currents and the fact that the dipole and Pauli approximations are avoided. The quantum part of the relativistic calculation is based on the determination of the transition charge currents in the Darwin solutions of the Dirac equation. 13 refs
International Nuclear Information System (INIS)
Galetti, D.; Kodama, T.; Nemes, M.C.
1986-10-01
The quantum relativistic Coulomb excitation process including reccil effects is studied in the plane wave Born approximation. Quantum and relativistic recoil effects allow for relatively large transverse momentum transfers, usually neglected. This specific feature is shown to modify the angular distribution of Coulomb induced fission fragmentation in an essential manner. In contrast with usual treatments it is found that these results compare favourably with recent data. (Authors) [pt
Study of projectile fragmentation in the reaction (158 A GeV) Pb + Pb using CR-39
Qureshi, I E; Javed, M T; Manzoor, S; Sher, G; Aleem, F; Khan, H A
2005-01-01
The fragmentation of Pb ions at 158 A GeV energy produced in the interaction with Pb target has been studied using a CR-39 track detector. A stack comprising of 64 detectors was prepared such that a target of 1 cm thickness was sandwiched between the sheets of CR-39. The purpose of this exposure geometry was to calibrate CR-39 with respect to relativistic heavy ions as well as to study the fragmentation of Pb ions at 158 A GeV energy. The exposure was carried out at the SPS beam facility of CERN at normal incidence with a fluence of . Two detectors from the exposed stack have been selected for this study: one before and the other after the target material. After etching, the detectors were scanned using an optical microscope and the etched track lengths and the diameters of the track openings were measured manually. Considering that the lengths of tracks provide the best charge resolution for Z>65, we have measured track lengths for a sufficiently large number of fragments to identify individual charge states...
Heavy neutron-deficient radioactive beams: fission studies and fragment distributions
Energy Technology Data Exchange (ETDEWEB)
Schmidt, K.H.; Benlliure, J.; Heinz, A.; Voss, B. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Boeckstiegel, C.; Grewe, A.; Steinhaeuser, S.; Clerc, H.G.; Jong, M. de; Junghans, A.R.; Mueller, J. [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik; Pfuetzner, M. [Warsaw Univ. (Poland). Inst. of Experimental Physics
1998-02-01
The secondary-beam facility of GSI Darmstadt was used to study the fission process of short-lived radioactive nuclei. Relativistic secondary projectiles were produced by fragmentation of a 1 A GeV {sup 238}U primary beam and identified in nuclear charge and mass number. Their production cross sections were determined, and the fission competition in the statistical deexcitation was deduced for long isotopical chains. New results on the enhancement of the nuclear level density in spherical and deformed nuclei due to collective rotational and vibrational excitations were obtained. Using these reaction products as secondary beams, the dipole giant resonance was excited by electromagnetic interactions in a secondary lead target, and fission from excitation energies around 11 MeV was induced. The fission fragments were identified in nuclear charge, and their velocity vectors were determined. Elemental yields and total kinetic energies have been determined for a number of neutron-deficient actinides and preactinides which were not accessible with conventional techniques. The characteristics of multimodal fission of nuclei around {sup 226}Th were systematically investigated and related to the influence of shell effects on the potential energy and on the level density between fission barrier and scission. A systematic view on the large number of elemental yields measured gave rise to a new interpretation of the enhanced production of even elements in nuclear fission and allowed for a new understanding of pair breaking in large-scale collective motion. (orig.)
A study of charge-pickup interactions by (158A GeV) Pb nuclei
International Nuclear Information System (INIS)
Sher, G.; Shahzad, M.I.
2012-01-01
Study of the relativistic heavy-ion collision is important to focus on probing phase transitions between hadrons and quark-gluon phases in the extreme conditions of temperature and density of nuclear matter formed in the collisions. These states of nuclear matter are expected to be created in relativistic nuclear collisions with large overlap of interacting nuclei, the Lorentz-boosted Coulomb potential Vc proportional to alpha gamma Z/b of a partner with charge Z is very strong, where b is impact parameter and is the fine structure constant. Either one or both nuclei may be disintegrated by the electromagnetic forces in ultra-peripheral collisions at b = R1 + R2, where R1 and R2 are the nuclear radii. This distinct feature of electromagnetic dissociation makes it possible to study the behavior of nuclear matter under electromagnetic fields. The nuclear charge-pickup ( delta Z = +1) by Pb projectiles at energy 158A GeV interacting with targets Bi, Pb, Cu and Al was investigated using CR39 nuclear track detectors. The target-detector stacks were exposed at CERN SPS beam facility. The projectile and fragments charge states have been identified using the etch-cone lengths for charge-pickup at Z = 83 of residual nuclei. Our measured charge-pickup cross sections (delta Z = +1) are shown. It was observed that for the heavy targets the increase in the cross section is anticipated by substantial contribution of electromagnetic dissociation process of production by virtual photons which is almost negligible at 10.6A GeV. In the light target region, our measured cross sections and charge-pickup cross sections reported at energy 10.6A GeV show dominant nuclear contribution and very small contribution of electromagnetic dissociation term. A strong dependence of charge-pickup cross sections on the target mass number was observed particularly in the heavy targets. (orig./A.B.)
Relativistic Energy Density Functionals: Exotic modes of excitation
International Nuclear Information System (INIS)
Vretenar, D.; Paar, N.; Marketin, T.
2008-01-01
The framework of relativistic energy density functionals has been applied to the description of a variety of nuclear structure phenomena, not only in spherical and deformed nuclei along the valley of β-stability, but also in exotic systems with extreme isospin values and close to the particle drip-lines. Dynamical aspects of exotic nuclear structure have been investigated with the relativistic quasiparticle random-phase approximation. We present results for the evolution of low-lying dipole (pygmy) strength in neutron-rich nuclei, and charged-current neutrino-nucleus cross sections.
Diquark fragmentation in leptoproduction of hadrons
International Nuclear Information System (INIS)
Beavis, D.; Desai, B.R.
1981-08-01
In the analysis of the leptoproduction data for the charge ratios of hadrons, the Sukhatme, Lassila and Orava (SLO) model for diquark fragmentation is shown to be consistent with the hypothesis of a diquark acting as a single unit. The baryon contribution to the charge ratio, ignored earlier by SLO, makes a significant effect. (author)
Recombination plus fragmentation model at RHIC: elliptic flow
Energy Technology Data Exchange (ETDEWEB)
Nonaka, C [Department of Physics, Duke University, Durham, NC 27708 (United States); Fries, R J [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Mueller, B [Department of Physics, Duke University, Durham, NC 27708 (United States); Bass, S A [Department of Physics, Duke University, Durham, NC 27708 (United States); RIKEN BNL Research Center, Brookhaven National Laboratory, Upton, NY 11973 (United States); Asakawa, M [Department of Physics, Osaka University, Toyonaka 560-0043 (Japan)
2005-04-01
We discuss hadron production in relativistic heavy-ion collisions in the framework of the recombination and fragmentation model. We propose elliptic flow as a useful tool for exploring final interactions of resonances, the hadron structure of exotic particles and the phase structure of the reaction.
Gluon fragmentation in T(1S) decays
International Nuclear Information System (INIS)
Bienlein, J.K.
1983-05-01
In T(1S) decays most observables (sphericity, charged multiplicity, photonic energy fraction, inclusive spectra) can be understood assuming that gluons fragment like quarks. New results from LENA use the (axis-independent) Fox-Wolfram moments for the photonic energy deposition. Continuum reactions show 'standard' Field-Feynman fragmentation. T(1S) decays show a significant difference in the photonic energy topology. It is more isotropic than with the Field-Feynman fragmentation scheme. Gluon fragmentation into isoscalar mesons (a la Peterson and Walsh) is excluded. But if one forces the leading particle to be isoscalar, one gets good agreement with the data. (orig.)
International Nuclear Information System (INIS)
Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni
2017-04-01
It is generally accepted that in order to describe the dynamics of relativistic particles in the laboratory (lab) frame it is sufficient to take into account the relativistic dependence of the particle momenta on the velocity. This solution of the dynamics problem in the lab frame makes no reference to Lorentz transformations. For this reason they are not discussed in particle tracking calculations in accelerator and plasma physics. It is generally believed that the electrodynamics problem can be treated within the same ''single inertial frame'' description without reference to Lorentz transformations. In particular, in order to evaluate radiation fields arising from charged particles in motion we need to know their velocities and positions as a function of the lab frame time t. The relativistic motion of a particle in the lab frame is described by Newton's second law ''corrected'' for the relativistic dependence of momentum on velocity. It is assumed in all standard derivations that one can perform identification of the trajectories in the source part of the usual Maxwell's equations with the trajectories vector x(t) measured (or calculated by using the corrected Newton's second law) in the lab frame. This way of coupling fields and particles is considered since more than a century as the relativistically correct procedure.We argue that this procedure needs to be changed, and we demonstrate the following, completely counterintuitive statement: the results of conventional theory of radiation by relativistically moving charges are not consistent with the principle of relativity. In order to find the trajectory of a particle in the lab frame consistent with the usual Maxwell's equations, one needs to solve the dynamic equation inmanifestly covariant form by using the coordinate-independent proper time τ to parameterize the particle world-line in space-time. We show that there is a difference between ''true'' particle trajectory vector x(t) calculated or measured in
Dielectric response of planar relativistic quantum plasmas
International Nuclear Information System (INIS)
Bardos, D.C.; Frankel, N.E.
1991-01-01
The dielectric response of planar relativistic charged particle-antiparticle plasmas is investigated, treating Fermi and Bose plasmas. The conductivity tensor in each case is derived in the self-consistent Random Phase Approximation. The tensors are then evaluated at zero temperature for the case of no external fields, leading to explicit dispersion relations for the electrodynamic modes of the plasma. The longitudinal and transverse modes are in general coupled for plasma layers. This coupling vanishes, however, in the zero field case, allowing 'effective' longitudinal and transverse dielectric functions to be defined in terms of components of the conductivity tensor. Solutions to the longitudinal mode equations (i.e. plasmon modes) are exhibited, while purely transverse modes are found not to exist. In the case of the Bose plasma the screening of a test charge is investigated in detail. 41 refs., 1 fig
Relativistic Outflows from ADAFs
Becker, Peter; Subramanian, Prasad; Kazanas, Demosthenes
2001-04-01
Advection-dominated accretion flows (ADAFs) have a positive Bernoulli parameter, and are therefore gravitationally bound. The Newtonian ADAF model has been generalized recently to obtain the ADIOS model that includes outflows of energy and angular momentum, thereby allowing accretion to proceed self-consistently. However, the utilization of a Newtonian gravitational potential limits the ability of this model to describe the inner region of the disk, where any relativistic outflows are likely to originate. In this paper we modify the ADIOS scenario to incorporate a seudo - Newtonian potential, which approximates the effects of general relativity. The analysis yields a unique, self - similar solution for the structure of the coupled disk/wind system. Interesting features of the new solution include the relativistic character of the outflow in the vicinity of the radius of marginal stability, which represents the inner edge of the quasi-Keplerian disk in our model. Our self - similar model may therefore help to explain the origin of relativistic jets in active galaxies. At large distances the radial dependence of the accretion rate approachs the unique form dot M ∝ r^1/2, with an associated density variation given by ρ ∝ r-1. This density variation agrees with that implied by the dependence of the X-ray hard time lags on the Fourier frequency for a number of accreting galactic black hole candidates. While intriguing, the results of our self-similar model need to be confirmed in the future by incorporating a detailed physical description of the energization mechanism that drives the outflow, which is likely to be powered by the shear of the underlying accretion disk.
Relativistic twins or sextuplets?
International Nuclear Information System (INIS)
Sheldon, Eric
2003-01-01
A recent study of the relativistic twin 'paradox' by Soni in this journal affirmed that 'A simple solution of the twin paradox also shows anomalous behaviour of rigidly connected distant clocks' but entailed a pedagogic hurdle which the present treatment aims to surmount. Two scenarios are presented: the first 'flight-plan' is akin to that depicted by Soni, with constant-velocity segments, while the second portrays an alternative mission undertaken with sustained acceleration and deceleration, illustrated quantitatively for a two-way spacecraft flight from Earth to Polaris (465.9 light years distant) and back
Relativistic twins or sextuplets?
Sheldon, E S
2003-01-01
A recent study of the relativistic twin 'paradox' by Soni in this journal affirmed that 'A simple solution of the twin paradox also shows anomalous behaviour of rigidly connected distant clocks' but entailed a pedagogic hurdle which the present treatment aims to surmount. Two scenarios are presented: the first 'flight-plan' is akin to that depicted by Soni, with constant-velocity segments, while the second portrays an alternative mission undertaken with sustained acceleration and deceleration, illustrated quantitatively for a two-way spacecraft flight from Earth to Polaris (465.9 light years distant) and back.
Relativistic quantum cryptography
Kaniewski, Jedrzej
Special relativity states that information cannot travel faster than the speed of light, which means that communication between agents occupying distinct locations incurs some minimal delay. Alternatively, we can see it as temporary communication constraints between distinct agents and such constraints turn out to be useful for cryptographic purposes. In relativistic cryptography we consider protocols in which interactions occur at distinct locations at well-defined times and we investigate why such a setting allows to implement primitives which would not be possible otherwise. (Abstract shortened by UMI.).
Localization of relativistic particles
International Nuclear Information System (INIS)
Omnes, R.
1997-01-01
In order to discuss localization experiments and also to extend the consistent history interpretation of quantum mechanics to relativistic properties, the techniques introduced in a previous paper [J. Math. Phys. 38, 697 (1997)] are applied to the localization of a photon in a given region of space. An essential requirement is to exclude arbitrarily large wavelengths. The method is valid for a particle with any mass and spin. Though there is no proper position operator for a photon, one never needs one in practice. Causality is valid up to exponentially small corrections. copyright 1997 American Institute of Physics
Corinaldesi, Ernesto
1963-01-01
Geared toward advanced undergraduate and graduate students of physics, this text provides readers with a background in relativistic wave mechanics and prepares them for the study of field theory. The treatment originated as a series of lectures from a course on advanced quantum mechanics that has been further amplified by student contributions.An introductory section related to particles and wave functions precedes the three-part treatment. An examination of particles of spin zero follows, addressing wave equation, Lagrangian formalism, physical quantities as mean values, translation and rotat
Relativistic quarkonium dynamics
International Nuclear Information System (INIS)
Sazdjian, H.
1985-06-01
We present, in the framework of relativistic quantum mechanics of two interacting particles, a general model for quarkonium systems satisfying the following four requirements: confinement, spontaneous breakdown of chiral symmetry, soft explicit chiral symmetry breaking, short distance interactions of the vector type. The model is characterized by two arbitrary scalar functions entering in the large and short distance interaction potentials, respectively. Using relationships with corresponding quantities of the Bethe-Salpeter equation, we also present the normalization condition of the wave functions, as well as the expressions of the meson decay coupling constants. The quark masses appear in this model as free parameters
International Nuclear Information System (INIS)
Araujo, Wilson Roberto Barbosa de
1995-01-01
In this dissertation, we present a model for the nucleon, which is composed by three relativistic quarks interacting through a contract force. The nucleon wave-function was obtained from the Faddeev equation in the null-plane. The covariance of the model under kinematical null-plane boots is discussed. The electric proton form-factor, calculated from the Faddeev wave-function, was in agreement with the data for low-momentum transfers and described qualitatively the asymptotic region for momentum transfers around 2 GeV. (author)
Relativistic nuclear collisions: theory
International Nuclear Information System (INIS)
Gyulassy, M.
1980-07-01
Some of the recent theoretical developments in relativistic (0.5 to 2.0-GeV/nucleon) nuclear collisions are reviewed. The statistical model, hydrodynamic model, classical equation of motion calculations, billiard ball dynamics, and intranuclear cascade models are discussed in detail. Inclusive proton and pion spectra are analyzed for a variety of reactions. Particular attention is focused on how the complex interplay of the basic reaction mechanism hinders attempts to deduce the nuclear matter equation of state from data. 102 references, 19 figures
[Relativistic heavy ion research
International Nuclear Information System (INIS)
1991-01-01
The present document describes our second-year application for a continuation grant on relativistic heavy-ion research at Nevis Laboratories, Columbia University, over the two-year period starting from November 15, 1990. The progress during the current budget year is presented. This year, construction of RHIC officially began. As a result, the entire Nevis nuclear physics group has made a coherent effort to create new proposal for an Open Axially Symmetric Ion Spectrometer (OASIS) proposal. Future perspectives and our plans for this proposal are described
Relativistic corrections for the conventional, classical Nyquist theorem
International Nuclear Information System (INIS)
Theimer, O.; Dirk, E.H.
1983-01-01
New expressions for the Nyquist theorem are derived under the condition in which the random thermal speed of electrons, in a system of charged particles, can approach the speed of light. Both the case in which, the electron have not drift velocity relative to the ions or neutral particles and the case in which drift occours are investigated. In both instances, the new expressions for the Nyquist theorem are found to contain relativistic correction terms; however for electron temperatures T approx. 10 9 K and drift velocity magnitudes w approx. 0.5c, where c is the speed of light, the effects of these correction terms are generally small. The derivation of these relativistic corrections is carried out by means of procedures developed in an earlier work. A relativistic distribution function, which incorporates a constant drift velocity with a random thermal velocity for a given particle species, is developed
On the relativistic quantum mechanics of two interacting spinless particles
International Nuclear Information System (INIS)
Rizov, V.A.; Sazdjian, H.; Todorov, I.T.
1984-05-01
The L 2 -scalar product ∫ PHI*(x)PSI(x) d 3 x is not appropriate for the space of states describing the center-of-mass relative motion of two relativistic particles whose interaction is given by an energy dependent quasipotential. The problem already appears in the relativistic quantum mechanics of a Klein-Gordon charged particle in an external field. We extend the methods developed for that case to study a two-particle system with an energy independent scalar interaction as well as the relativistic Coulomb problem. We write down a Poincare invariant inner product for which the eigenfunctions corresponding to different energy eigenvalues are orthogonal. We also construct a perturbative expansion for bound-state energy eigenvalues corresponding to an arbitrary energy dependent (quasipotential) correction to an unperturbed Hamiltonian with a known spectrum. The description of observables and transition probabilities for eigenvalue problems with a polynomial dependence on the spectral parameter is also discussed
Relativistic approach to nuclear structure
International Nuclear Information System (INIS)
Nguyen Van Giai; Bouyssy, A.
1987-03-01
Some recent works related with relativistic models of nuclear structure are briefly reviewed. The Dirac-Hartree-Fock and Dirac-Brueckner-Hartree-Fock are recalled and illustrated by some examples. The problem of isoscalar current and magnetic moments of odd nuclei is discussed. The application of the relativistic model to the nuclear response function is examined
Relativistic dynamics without conservation laws
Rothenstein, Bernhard; Popescu, Stefan
2006-01-01
We show that relativistic dynamics can be approached without using conservation laws (conservation of momentum, of energy and of the centre of mass). Our approach avoids collisions that are not easy to teach without mnemonic aids. The derivations are based on the principle of relativity and on its direct consequence, the addition law of relativistic velocities.
Relativistic non-Hamiltonian mechanics
International Nuclear Information System (INIS)
Tarasov, Vasily E.
2010-01-01
Relativistic particle subjected to a general four-force is considered as a nonholonomic system. The nonholonomic constraint in four-dimensional space-time represents the relativistic invariance by the equation for four-velocity u μ u μ + c 2 = 0, where c is the speed of light in vacuum. In the general case, four-forces are non-potential, and the relativistic particle is a non-Hamiltonian system in four-dimensional pseudo-Euclidean space-time. We consider non-Hamiltonian and dissipative systems in relativistic mechanics. Covariant forms of the principle of stationary action and the Hamilton's principle for relativistic mechanics of non-Hamiltonian systems are discussed. The equivalence of these principles is considered for relativistic particles subjected to potential and non-potential forces. We note that the equations of motion which follow from the Hamilton's principle are not equivalent to the equations which follow from the variational principle of stationary action. The Hamilton's principle and the principle of stationary action are not compatible in the case of systems with nonholonomic constraint and the potential forces. The principle of stationary action for relativistic particle subjected to non-potential forces can be used if the Helmholtz conditions are satisfied. The Hamilton's principle and the principle of stationary action are equivalent only for a special class of relativistic non-Hamiltonian systems.
Contraint's theory and relativistic dynamics
International Nuclear Information System (INIS)
Longhi, G.; Lusanna, L.
1987-01-01
The purpose of this Workshop was to examine the current situation of relativistic dynamics. In particular, Dirac-Bergmann's theory of constraints, which lies at the heart of gauge theories, general relativity, relativistic mechanics and string theories, was chosen as the unifying theoretical framework best suited to investigate such a field. The papers discussed were on general relativity; relativistic mechanics; particle physics and mathematical physics. Also discussed were the problems of classical and quantum level, namely the identification of the classical observables of constrained systems, the equivalence of the nonequivalence of the various ways to quantize such systems; the problem of the anomalies; the best geometrical approach to the theory of constraints; the possibility of unifying all the treatments of relativistic mechanics. This book compiles the papers presented at proceedings of relativistic dynamics and constraints theory
Relativistic centrifugal instability
Gourgouliatos, Konstantinos N.; Komissarov, Serguei S.
2018-03-01
Near the central engine, many astrophysical jets are expected to rotate about their axis. Further out they are expected to go through the processes of reconfinement and recollimation. In both these cases, the flow streams along a concave surface and hence, it is subject to the centrifugal force. It is well known that such flows may experience the centrifugal instability (CFI), to which there are many laboratory examples. The recent computer simulations of relativistic jets from active galactic nuclei undergoing the process of reconfinement show that in such jets CFI may dominate over the Kelvin-Helmholtz instability associated with velocity shear (Gourgouliatos & Komissarov). In this letter, we generalize the Rayleigh criterion for CFI in rotating fluids to relativistic flows using a heuristic analysis. We also present the results of computer simulations which support our analytic criterion for the case of an interface separating two uniformly rotating cylindrical flows. We discuss the difference between CFI and the Rayleigh-Taylor instability in flows with curved streamlines.
Relativistic heavy ion physics
International Nuclear Information System (INIS)
Hill, J.C.; Wohn, F.K.
1992-01-01
In 1992 a proposal by the Iowa State University experimental nuclear physics group entitled ''Relativistic Heavy Ion Physics'' was funded by the US Department of Energy, Office of Energy Research, for a three-year period beginning November 15, 1991. This is a progress report for the first six months of that period but, in order to give a wider perspective, we report here on progress made since the beginning of calendar year 1991. In the first section, entitled ''Purpose and Trends,'' we give some background on the recent trends in our research program and its evolution from an emphasis on nuclear structure physics to its present emphasis on relativistic heavy ion and RHIC physics. The next section, entitled, ''Physics Research Programs,'' is divided into three parts. First, we discuss our participation in the program to develop a large detector named PHENIX for the RHIC accelerator. Second, we outline progress made in the study of electromagnetic dissociation (ED). A highlight of this endeavor is experiments carried out with the 197 Au beam from the AGS accelerator in April 1991. Third, we discuss progress in completion of our nuclear structure studies. In the final section a list of publications, invited talks and contributed talks starting in 1991 is given
The relativistic feedback discharge model of terrestrial gamma ray flashes
Dwyer, Joseph R.
2012-02-01
As thunderclouds charge, the large-scale fields may approach the relativistic feedback threshold, above which the production of relativistic runaway electron avalanches becomes self-sustaining through the generation of backward propagating runaway positrons and backscattered X-rays. Positive intracloud (IC) lightning may force the large-scale electric fields inside thunderclouds above the relativistic feedback threshold, causing the number of runaway electrons, and the resulting X-ray and gamma ray emission, to grow exponentially, producing very large fluxes of energetic radiation. As the flux of runaway electrons increases, ionization eventually causes the electric field to discharge, bringing the field below the relativistic feedback threshold again and reducing the flux of runaway electrons. These processes are investigated with a new model that includes the production, propagation, diffusion, and avalanche multiplication of runaway electrons; the production and propagation of X-rays and gamma rays; and the production, propagation, and annihilation of runaway positrons. In this model, referred to as the relativistic feedback discharge model, the large-scale electric fields are calculated self-consistently from the charge motion of the drifting low-energy electrons and ions, produced from the ionization of air by the runaway electrons, including two- and three-body attachment and recombination. Simulation results show that when relativistic feedback is considered, bright gamma ray flashes are a natural consequence of upward +IC lightning propagating in large-scale thundercloud fields. Furthermore, these flashes have the same time structures, including both single and multiple pulses, intensities, angular distributions, current moments, and energy spectra as terrestrial gamma ray flashes, and produce large current moments that should be observable in radio waves.
Electromagnetic processes in relativistic heavy ion collisions
International Nuclear Information System (INIS)
Bertulani, C.A.; Universidade Federal do Rio de Janeiro; Baur, G.
1987-10-01
A study of the processes generated by the electromagnetic interaction in relativistic nuclear, and atomic collisions is presented. There is nowadays a vivid interest in this field due to the construction of relativistic heavy ion accelerators. Certainly, the most important purpose of these relativistic heavy ion machines is the study of nuclear matter under extreme conditions. In central nucleus-nucleus collisions one hopes to observe new forms of nuclear matter, like the quark-gluon plasma. On the other hand, very strong electromagnetic fields for a very short time are present in distant collisions with no nuclear contact. Such fields can also lead to interesting effects, which are discussed here. There has been many interesting theoretical and experimental developments on this subject, and new areas of research were opened. Of special interest is, e.g., the case of nuclear fragmentation. This is accomplished through the excitation of giant resonances or by direct breakt-up of the nuclei by means of their electromagnetic interaction. It is shown that this process can be used to study nuclear structure properties which are not accessible by means of the traditional electromagnetic excitation at nonrelativistic energies. The creation of particles is also of interest due the large cross sections, specially in the case of electron-positron pair creation. Although to explain the many processes originated in this way one can develop very elaborate and complicated calculations, the results can be understood in very simple terms because of our almost complete comprehension of the electromagntic interaction. For those processes where the electromagntic interaction plays the dominant role this is clearly a very useful tool for the investigation of the structures created by the strong interaction in the nuclei or hadrons. (orig.)
Structural mechanisms of photoeffect in polyimide structures containing heterocyclic fragments
International Nuclear Information System (INIS)
Aleksandrova, E. L.
2006-01-01
Trends in the variation in the quantum yields of charge-carrier photogeneration in polyimide structures containing heterocyclic fragments are studied. It is shown that the efficiency of sensitization of polyimides depends on the donor and acceptor properties of the fragments of monomeric units of the polyimide. It is established that the range of spectral sensitivity for heterocyclic fragments representing intramolecular complexes with charge transport is wider than that for heterocycles that do not represent such complexes
Relativistic hydrodynamic evolutions with black hole excision
International Nuclear Information System (INIS)
Duez, Matthew D.; Shapiro, Stuart L.; Yo, H.-J.
2004-01-01
We present a numerical code designed to study astrophysical phenomena involving dynamical spacetimes containing black holes in the presence of relativistic hydrodynamic matter. We present evolutions of the collapse of a fluid star from the onset of collapse to the settling of the resulting black hole to a final stationary state. In order to evolve stably after the black hole forms, we excise a region inside the hole before a singularity is encountered. This excision region is introduced after the appearance of an apparent horizon, but while a significant amount of matter remains outside the hole. We test our code by evolving accurately a vacuum Schwarzschild black hole, a relativistic Bondi accretion flow onto a black hole, Oppenheimer-Snyder dust collapse, and the collapse of nonrotating and rotating stars. These systems are tracked reliably for hundreds of M following excision, where M is the mass of the black hole. We perform these tests both in axisymmetry and in full 3+1 dimensions. We then apply our code to study the effect of the stellar spin parameter J/M 2 on the final outcome of gravitational collapse of rapidly rotating n=1 polytropes. We find that a black hole forms only if J/M 2 2 >1, the collapsing star forms a torus which fragments into nonaxisymmetric clumps, capable of generating appreciable 'splash' gravitational radiation
Analytic study of 1D diffusive relativistic shock acceleration
Energy Technology Data Exchange (ETDEWEB)
Keshet, Uri, E-mail: ukeshet@bgu.ac.il [Physics Department, Ben-Gurion University of the Negev, POB 653, Be' er-Sheva 84105 (Israel)
2017-10-01
Diffusive shock acceleration (DSA) by relativistic shocks is thought to generate the dN / dE ∝ E{sup −p} spectra of charged particles in various astronomical relativistic flows. We show that for test particles in one dimension (1D), p {sup −1}=1−ln[γ{sub d}(1+β{sub d})]/ln[γ{sub u}(1+β{sub u})], where β{sub u}(β{sub d}) is the upstream (downstream) normalized velocity, and γ is the respective Lorentz factor. This analytically captures the main properties of relativistic DSA in higher dimensions, with no assumptions on the diffusion mechanism. Unlike 2D and 3D, here the spectrum is sensitive to the equation of state even in the ultra-relativistic limit, and (for a J(üttner-Synge equation of state) noticeably hardens with increasing 1<γ{sub u}<57, before logarithmically converging back to p (γ{sub u→∞})=2. The 1D spectrum is sensitive to drifts, but only in the downstream, and not in the ultra-relativistic limit.
Relativistic nonlinear electrodynamics the QED vacuum and matter in super-strong radiation fields
Avetissian, Hamlet K
2016-01-01
This revised edition of the author’s classic 2006 text offers a comprehensively updated review of the field of relativistic nonlinear electrodynamics. It explores the interaction of strong and super-strong electromagnetic/laser radiation with the electromagnetic quantum vacuum and diverse types of matter – including free charged particles and antiparticles, acceleration beams, plasma and plasmous media. The appearance of laser sources of relativistic and ultra-relativistic intensities over the last decade has stimulated investigation of a large class of processes under such super-strong radiation fields. Revisions for this second edition reflect these developments and the book includes new chapters on Bremsstrahlung and nonlinear absorption of superintense radiation in plasmas, the nonlinear interaction of relativistic atoms with intense laser radiation, nonlinear interaction of strong laser radiation with Graphene, and relativistic nonlinear phenomena in solid-plasma targets under supershort laser pul...
Fragmentation of 22Ne in emulsion at 4.1 A GeV/c
International Nuclear Information System (INIS)
El-Naghy, A.; Krasnov, S.A.; Tolstov, K.D.
1987-01-01
Charge distributions of projectile fragments produced in the interactions of 22 Ne beams with emulsion at 4.1 A GeV/c have been studied. Correlations between projectile and target fragments and among projectile fragments are presented. The change of charge yield distribution with the violence of the collision has been shown. The present analysis contradicts theoretical calculations describing the inclusive charge yield distribution of fragments by a single process
Lorentzian Type Force on a Charge at Rest
Directory of Open Access Journals (Sweden)
Zelsacher R.
2014-01-01
Full Text Available A remarkable achievement of theoretical physics is the explanation of magnetic effects, described by the Lorentz force, to be corollaries of charge i nvariance, Coulombs Law and the Lorentz transformation. The relativistic explanation of magnetism is based essentially on the calculation of Coulomb forces between mo ving charges in the labo- ratory reference system. We will show presently that the ideas used for the relativistic explanation of magnetism also lead to a force on a charge at rest by moving charges, which we dub “Lorentzian type force on a charge at rest”.
International Nuclear Information System (INIS)
Gosset, J.
1981-07-01
The following topics are discussed: production of very neutron-rich nuclei; evidence for projectile fragments with short mean free path; generation of entropy; results of interferometry and multiplicity selected experiments; finally the crucial need for measuring and calculating global variables
International Nuclear Information System (INIS)
Donker, H.C.; Katsnelson, M.I.; De Raedt, H.; Michielsen, K.
2016-01-01
The logical inference approach to quantum theory, proposed earlier De Raedt et al. (2014), is considered in a relativistic setting. It is shown that the Klein–Gordon equation for a massive, charged, and spinless particle derives from the combination of the requirements that the space–time data collected by probing the particle is obtained from the most robust experiment and that on average, the classical relativistic equation of motion of a particle holds. - Highlights: • Logical inference applied to relativistic, massive, charged, and spinless particle experiments leads to the Klein–Gordon equation. • The relativistic Hamilton–Jacobi is scrutinized by employing a field description for the four-velocity. • Logical inference allows analysis of experiments with uncertainty in detection events and experimental conditions.
Photoionization at relativistic energies
International Nuclear Information System (INIS)
Ionescu, D.C.; Technische Univ. Dresden; Soerensen, A.H.; Belkacem, A.
2000-11-01
At MeV energies and beyond the inner-shell vacancy production cross section associated with the photoelectric and Compton effect decrease with increasing photon energy. However, when the photon energy exceeds twice the rest energy of the electron, ionization of a bound electron may be catalyzed by the creation of an electron-positron pair. Distinctly different from all other known mechanisms for inner-shell vacancy production by photons, we show that the cross section for this ''vacuum-assisted photoionization'' increases with increasing photon energy and then saturates. As a main result, we predict that vacuum-assisted photoionization will dominate the other known photoionization mechanisms in the highly relativistic energy regime. (orig.)
Relativistic thermodynamics of fluids
International Nuclear Information System (INIS)
Souriau, J.-M.
1977-05-01
The relativistic covariant definition of a statistical equilibrium, applied to a perfect gas, involves a 'temperature four-vector', whose direction is the mean velocity of the fluid, and whose length is the reciprocal temperature. The hypothesis of this 'temperature four-vector' being a relevant variable for the description of the dissipative motions of a simple fluid is discussed. The kinematics is defined by using a vector field and measuring the number of molecules. Such a dissipative fluid is subject to motions involving null entropy generation; the 'temperature four-vector' is then a Killing vector; the equations of motion can be completely integrated. Perfect fluids can be studied by this way and the classical results of Lichnerowicz are obtained. In weakly dissipative motions two viscosity coefficient appear together with the heat conductibility coefficient. Two other coefficients perharps measurable on real fluids. Phase transitions and shock waves are described with using the model [fr
Relativistic heavy ion physics
International Nuclear Information System (INIS)
Hill, J.C.; Wohn, F.K.
1993-01-01
This is a progress report for the period May 1992 through April 1993. The first section, entitled ''Purpose and Trends, gives background on the recent trends in the research program and its evolution from an emphasis on nuclear structure physics to its present emphasis on relativistic heavy ion and RHIC physics. The next section, entitled ''Physics Research Progress'', is divided into four parts: participation in the program to develop a large detector named PHENIX for the RHIC accelerator; joining E864 at the AGS accelerator and the role in that experiment; progress made in the study of electromagnetic dissociation highlight of this endeavor is an experiment carried out with the 197 Au beam from the AGS accelerator in April 1992; progress in completion of the nuclear structure studies. In the final section a list of publications, invited talks, and contributed talks is given
Relativistic plasma dispersion functions
International Nuclear Information System (INIS)
Robinson, P.A.
1986-01-01
The known properties of plasma dispersion functions (PDF's) for waves in weakly relativistic, magnetized, thermal plasmas are reviewed and a large number of new results are presented. The PDF's required for the description of waves with small wave number perpendicular to the magnetic field (Dnestrovskii and Shkarofsky functions) are considered in detail; these functions also arise in certain quantum electrodynamical calculations involving strongly magnetized plasmas. Series, asymptotic series, recursion relations, integral forms, derivatives, differential equations, and approximations for these functions are discussed as are their analytic properties and connections with standard transcendental functions. In addition a more general class of PDF's relevant to waves of arbitrary perpendicular wave number is introduced and a range of properties of these functions are derived
Cross sections and kinematics of proton induced fragmentation of carbon
International Nuclear Information System (INIS)
Streibel, T.; Roecher, H.; Huentrup, G.; Heinrich, W.
1997-01-01
Charge changing fragmentation cross sections for C at a proton energy of about 70 MeV were measured. The discrepancies between measurement and model predictions indicate the necessity of further investigations. We have also measured distributions of fragment emission angles which can be described using a model with a momentum transfer to the fragmenting nucleus. The developed model leads to predictions for momentum distributions of proton induced target fragments of C at small energies. (orig.)
Cross sections and kinematics of proton induced fragmentation of carbon
Energy Technology Data Exchange (ETDEWEB)
Streibel, T; Roecher, H; Huentrup, G; Heinrich, W [Siegen Univ. (Germany). Dept. of Physics
1997-09-01
Charge changing fragmentation cross sections for C at a proton energy of about 70 MeV were measured. The discrepancies between measurement and model predictions indicate the necessity of further investigations. We have also measured distributions of fragment emission angles which can be described using a model with a momentum transfer to the fragmenting nucleus. The developed model leads to predictions for momentum distributions of proton induced target fragments of C at small energies. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Kipping, David, E-mail: dkipping@astro.columbia.edu [Department of Astronomy, Columbia University, 550 W. 120th St., New York, NY 10027 (United States)
2017-06-01
One proposed method for spacecraft to reach nearby stars is by accelerating sails using either solar radiation pressure or directed energy. This idea constitutes the thesis behind the Breakthrough Starshot project, which aims to accelerate a gram-mass spacecraft up to one-fifth the speed of light toward Proxima Centauri. For such a case, the combination of the sail’s low mass and relativistic velocity renders previous treatments incorrect at the 10% level, including that of Einstein himself in his seminal 1905 paper introducing special relativity. To address this, we present formulae for a sail’s acceleration, first in response to a single photon and then extended to an ensemble. We show how the sail’s motion in response to an ensemble of incident photons is equivalent to that of a single photon of energy equal to that of the ensemble. We use this principle of ensemble equivalence for both perfect and imperfect mirrors, enabling a simple analytic prediction of the sail’s velocity curve. Using our results and adopting putative parameters for Starshot , we estimate that previous relativistic treatments underestimate the spacecraft’s terminal velocity by ∼10% for the same incident energy. Additionally, we use a simple model to predict the sail’s temperature and diffraction beam losses during the laser firing period; this allows us to estimate that, for firing times of a few minutes and operating temperatures below 300°C (573 K), Starshot will require a sail that absorbs less than one in 260,000 photons.
International Nuclear Information System (INIS)
Kipping, David
2017-01-01
One proposed method for spacecraft to reach nearby stars is by accelerating sails using either solar radiation pressure or directed energy. This idea constitutes the thesis behind the Breakthrough Starshot project, which aims to accelerate a gram-mass spacecraft up to one-fifth the speed of light toward Proxima Centauri. For such a case, the combination of the sail’s low mass and relativistic velocity renders previous treatments incorrect at the 10% level, including that of Einstein himself in his seminal 1905 paper introducing special relativity. To address this, we present formulae for a sail’s acceleration, first in response to a single photon and then extended to an ensemble. We show how the sail’s motion in response to an ensemble of incident photons is equivalent to that of a single photon of energy equal to that of the ensemble. We use this principle of ensemble equivalence for both perfect and imperfect mirrors, enabling a simple analytic prediction of the sail’s velocity curve. Using our results and adopting putative parameters for Starshot , we estimate that previous relativistic treatments underestimate the spacecraft’s terminal velocity by ∼10% for the same incident energy. Additionally, we use a simple model to predict the sail’s temperature and diffraction beam losses during the laser firing period; this allows us to estimate that, for firing times of a few minutes and operating temperatures below 300°C (573 K), Starshot will require a sail that absorbs less than one in 260,000 photons.
Rotating relativistic neutron stars
Energy Technology Data Exchange (ETDEWEB)
Weber, F.; Glendenning, N.K.
1991-07-21
Models of rotating neutron stars are constructed in the framework of Einstein's theory of general relativity. For this purpose a refined version of Hartle's method is applied. The properties of these objects, e.g. gravitational mass, equatorial and polar radius, eccentricity, red- and blueshift, quadrupole moment, are investigated for Kepler frequencies of 4000 s{sup {minus}1} {le} {Omega}{sub K} {le} 9000 s{sup {minus}1}. Therefore a self-consistency problem inherent in the determination of {Omega}{sub K} must be solved. The investigation is based on neutron star matter equations of state derived from the relativistic Martin-Schwinger hierarch of coupled Green's functions. By means of introducing the Hartree, Hartree-Fock, and ladder ({Lambda}) approximations, models of the equation of state derived. A special feature of the latter approximation scheme is the inclusion of dynamical two-particle correlations. These have been calculated from the relativistic T-matrix applying both the HEA and Bonn meson-exchange potentials of the nucleon-nucleon force. The nuclear forces of the former two treatments are those of the standard scalar-vector-isovector model of quantum hadron dynamics, with parameters adjusted to the nuclear matter data. An important aspect of this work consists in testing the compatibility of different competing models of the nuclear equation of state with data on pulsar periods. By this the fundamental problem of nuclear physics concerning the behavior of the equation of state at supernuclear densities can be treated.
Some problems in relativistic thermodynamics
International Nuclear Information System (INIS)
Veitsman, E. V.
2007-01-01
The relativistic equations of state for ideal and real gases, as well as for various interface regions, have been derived. These dependences help to eliminate some controversies in the relativistic thermodynamics based on the special theory of relativity. It is shown, in particular, that the temperature of system whose velocity tends to the velocity of light in vacuum varies in accordance with the Ott law T = T 0 /√1 - v 2 /c 2 . Relativistic dependences for heat and mass transfer, for Ohm's law, and for a viscous flow of a liquid have also been derived
Relativistic rise measurement by cluster counting method in time expansion chamber
International Nuclear Information System (INIS)
Rehak, P.; Walenta, A.H.
1979-10-01
A new approach to the measurement of the ionization energy loss for the charged particle identification in the region of the relativistic rise was tested experimentally. The method consists of determining in a special drift chamber (TEC) the number of clusters of the primary ionization. The method gives almost the full relativistic rise and narrower landau distribution. The consequences for a practical detector are discussed
International Nuclear Information System (INIS)
Spies, H.
1992-06-01
In the framework of the experimental program at the accelerator facilities SIS/ESR of the Society for Heavy-Ion research in Darmstadt one of the essential research aims of the LAND collaboration is the study of high-lying collective states after electromagnetic excitation in heavy-ion collisions at nearly relativistic beam energies. By the exchange of virtual photons with high energy giant resonances are excited with high probabilities. The main decay channel of giant resonances in heavy nuclei is the emission of neutrons as well as below the particle threshold the emission of γ radiation. For the study of these states a detector system was developed, which makes the kinematically complete measurement of all reaction partners possible. For the determination of the neutron energy serves the Large Area Neutron Detector LAND, a time-of-flight spectrometer for high-energetic neutrons. For the measurement of the γ radiation emitted by the excited projectile the target is surrounded by an array of 48 BaF 2 crystals. A radiation detector system consisting of 6 single detectors and further 5 help detectors allows together with the magnetic spectrometer ALADIN the identification of the heavy projectile fragments by charge, momentum, and mass. Four position-sensitive plastic scintillators serve for the measurement of the trajectory of the projectile respectively the projectile fragments in front and behind the deviating magnet. Additionally with these detectors the velocity is measured. For the determination of the nuclear charge of the projectile fragments serve a multiple-ionization chamber and a Cherenkov detector. In this thesis the development and taking into operation of the LAND radiation detector system is described. (orig./HSI) [de
Electromagnetic field of a circular beam of relativistic particles
International Nuclear Information System (INIS)
Vybiral, B.
1978-01-01
The generalized Coulomb law and the generalized Biot-Savart-Laplace law are derived for an element of a beam of charged relativistic particles moving generally irregularly. These laws are utilized for the description of an electromagnetic field of a circular beam of relativistic regularly moving particles. It is shown that in the points on the axis of the beam the intensity of the electric field is given by an expression precisely corresponding to the classical Coulomb law for charges at rest and the induction of the magnetic field corresponds to the classical Biot-Savart-Laplace law for conductive currents. From the numerical solution it follows that in the points outside the axis the induction of the magnetic field rises with the velocity of the particles. For a velocity nearing that of light in vacuum it assumes a definite value (with the exception of the points lying on the beam). (author)
Ultra-relativistic heavy ion collisions in a multi-string model
International Nuclear Information System (INIS)
Werner, K.
1987-01-01
We present a model for ultra-relativistic heavy ion collisions based on color string formation and subsequent independent string fragmentation. Strings are formed due to color exchange between quarks at each individual nucleon nucleon collision. The fragmentation is treated as in e + e - or lepton nucleon scattering. Calculation for pp, pA, and AA were carried out using the Monte Carlo code VENUS for Very Energetic Nuclear Scattering (version 1.0). 20 refs., 6 figs
Relativistic theory of stopping for heavy ions
International Nuclear Information System (INIS)
Lindhard, J.; So/rensen, A.H.
1996-01-01
We calculate the electronic stopping power and the corresponding straggling for ions of arbitrary charge number, penetrating matter at any relativistic energy. The stopping powers are calculated by a simple method. Its starting point is the deviation of the precise theory from first-order quantum perturbation. We show that this deviation can be expressed in terms of the transport cross section, σ tr , for scattering of a free electron by the ion. In the nonrelativistic case the deviation is precisely the Bloch correction to Bethe close-quote s formula; we look into the nonrelativistic case in order to clarify both some features of our method and a seeming paradox in Rutherford scattering. The corresponding relativistic correction is obtained from σ tr for scattering of a Dirac electron in the ion potential. Here, the major practical advantage of the method shows up; we need not find the scattering distribution, but merely a single quantity, σ tr , determined by differences of successive phase shifts. For a point nucleus our results improve and extend those of Ahlen. Our final results, however, are based on atomic nuclei with standard radii. Thereby, the stopping is changed substantially already for moderate values of γ=(1-v 2 /c 2 ) -1/2 . An asymptotic saturation in stopping is obtained. Because of finite nuclear size, recoil corrections remain negligible at all energies. The average square fluctuation in energy loss is calculated as a simple fluctuation cross section for a free electron. The fluctuation in the relativistic case is generally larger than that of the perturbation formula, by a factor of ∼2 endash 3 for heavy ions. But the finite nuclear radius leads to a strong reduction at high energies and the elimination of the factor γ 2 belonging to point nuclei. copyright 1996 The American Physical Society
Fragmentation of deuterons on nucleons in the infinite momentum frame
International Nuclear Information System (INIS)
Dolidze, M.G.; Lykasov, G.I.
1989-01-01
A method for the analysis of interactions between fast deuterons and nucleons is developed taking into account both the relativistic effects in the deuteron and the mechanism of their interaction. The inclusive proton spectra and the polarization characteristics are investigated on the example of the fragmentation type processes of deuterons on nucleons. A strong sensitivity of the deuteron polarization tensor component T 20 both to the reaction mechanisms and to the relativistic structure of the deuteron is shown. The probable existence of the 6q-state in the deuteron in those reactions is discussed. 24 refs.; 3 figs
Special traits of the millimeter wave relativistic magnetron
International Nuclear Information System (INIS)
Berdin, S.A.; Chizhov, K.V.; Gadetski, N.P.; Korenev, V.G.; Lebedenko, A.N.; Marchenko, M.I.; Magda, I.I.; Melezhik, O.G.; Sinitsin, V.G.; Soshenko, V.A.
2014-01-01
A 8 mm band relativistic magnetron is investigated experimentally and by means of numerical simulation. The physical effects are analyzed which influence negatively the r.f. generation. The processes capable of reducing effectiveness of the generation and duration of the generated pulse include forward and backward axial flows of electrons, and intense electric fields - the generated microwaves and the fields owing to the space charge
International Nuclear Information System (INIS)
LaJohn, L. A.
2010-01-01
The nonrelativistic (nr) impulse approximation (NRIA) expression for Compton-scattering doubly differential cross sections (DDCS) for inelastic photon scattering is recovered from the corresponding relativistic expression (RIA) of Ribberfors [Phys. Rev. B 12, 2067 (1975)] in the limit of low momentum transfer (q→0), valid even at relativistic incident photon energies ω 1 >m provided that the average initial momentum of the ejected electron i > is not too high, that is, i > b 1 >m using nr expressions when θ is small. For example, a 1% accuracy can be obtained when ω 1 =1 MeV if θ 1 increases into the MeV range, the maximum θ at which an accurate Compton peak can be obtained from nr expressions approaches closer to zero, because the θ at which the relativistic shift of CP to higher energy is greatest, which starts at 180 deg. when ω 1 min ,ρ rel ) (where p min is the relativistic version of the z component of the momentum of the initial electron and ρ rel is the relativistic charge density) and K(p min ) on p min . This characterization approach was used as a guide for making the nr QED S-matrix expression for the Compton peak kinematically relativistic. Such modified nr expressions can be more readily applied to large systems than the fully relativistic version.
Conductivity of a relativistic plasma
Energy Technology Data Exchange (ETDEWEB)
Braams, B.J.; Karney, C.F.F.
1989-03-01
The collision operator for a relativistic plasma is reformulated in terms of an expansion in spherical harmonics. This formulation is used to calculate the electrical conductivity. 13 refs., 1 fig., 1 tab.
Relativistic description of atomic nuclei
International Nuclear Information System (INIS)
Krutov, V.A.
1985-01-01
Papers on the relativistic description of nuclei are reviewed. The Brown and Rho ''small'' bag'' model is accepted for hardrons. Meson exchange potentials of the nucleon-nucleon interaction have been considered. Then the transition from a system of two interacting nucleons has been performed to the relativistic nucleus description as a multinucleon system on the basis of OBEP (one-boson exchange potential). The proboem of OPEP (one-pion-exchange potential) inclusion to a relativistic scheme is discussed. Simplicity of calculations and attractiveness of the Walecka model for specific computations and calculations was noted. The relativistic model of nucleons interacting through ''effective'' scalar and vector boson fields was used in the Walacka model for describing neutronaand nuclear mater matters
Conductivity of a relativistic plasma
International Nuclear Information System (INIS)
Braams, B.J.; Karney, C.F.F.
1989-03-01
The collision operator for a relativistic plasma is reformulated in terms of an expansion in spherical harmonics. This formulation is used to calculate the electrical conductivity. 13 refs., 1 fig., 1 tab
Energy Technology Data Exchange (ETDEWEB)
Moeller, Peter [Los Alamos National Laboratory, Theoretical Division, Los Alamos, NM (United States); Ichikawa, Takatoshi [Kyoto University, Yukawa Institute for Theoretical Physics, Kyoto (Japan)
2015-12-15
We propose a method to calculate the two-dimensional (2D) fission-fragment yield Y(Z,N) versus both proton and neutron number, with inclusion of odd-even staggering effects in both variables. The approach is to use the Brownian shape-motion on a macroscopic-microscopic potential-energy surface which, for a particular compound system is calculated versus four shape variables: elongation (quadrupole moment Q{sub 2}), neck d, left nascent fragment spheroidal deformation ε{sub f1}, right nascent fragment deformation ε{sub f2} and two asymmetry variables, namely proton and neutron numbers in each of the two fragments. The extension of previous models 1) introduces a method to calculate this generalized potential-energy function and 2) allows the correlated transfer of nucleon pairs in one step, in addition to sequential transfer. In the previous version the potential energy was calculated as a function of Z and N of the compound system and its shape, including the asymmetry of the shape. We outline here how to generalize the model from the ''compound-system'' model to a model where the emerging fragment proton and neutron numbers also enter, over and above the compound system composition. (orig.)
Relativistic heavy-ion physics
Herrera Corral, G
2010-01-01
The study of relativistic heavy-ion collisions is an important part of the LHC research programme at CERN. This emerging field of research focuses on the study of matter under extreme conditions of temperature, density, and pressure. Here we present an introduction to the general aspects of relativistic heavy-ion physics. Afterwards we give an overview of the accelerator facility at CERN and then a quick look at the ALICE project as a dedicated experiment for heavy-ion collisions.
Modeling terrestrial gamma ray flashes produced by relativistic feedback discharges
Liu, Ningyu; Dwyer, Joseph R.
2013-05-01
, the continuous propagation of the streamer tends to be unstable, because it does not expand like the conventional positive streamer. Its head electric field continues to increase and can reach half of the conventional breakdown threshold field, which results in an ion density of 3- 10×1014m-3 in the channel immediately following the head. The spatial width of the high field region in the streamer head is about 100 m and the streamer speed is about 5×105 m/s. As a result, conventional positive streamers can be initiated from thundercloud hydrometeors or inhomogeneities of enhanced conductivities of millimeter sizes in the relativistic feedback streamer head and the positive streamers may further result in the formation of leaders. In addition, a relativistic feedback streamer can result in a charge moment change of several tens of coulomb-kilometers in a few tens of milliseconds, indicating that the relativistic feedback discharge process could be an important component for thundercloud charge dynamics.
Nonlinear dynamics of the relativistic standard map
International Nuclear Information System (INIS)
Nomura, Y.; Ichikawa, Y.H.; Horton, W.
1991-01-01
Heating and acceleration of charged particles by RF fields have been extensively investigated by the standard map (ST). Thus, it is natural to pose the question asking how the relativistic effects change the nonlinear dynamical behavior described by the classical ST map. The authors show that the speed of light limits the rate of advance of the phase in the relativistic standard map (RST) and introduces KAM surfaces persisting in the high momentum region. The RST map is a two parameter (k, β = ω/kc) family of dynamics reducing to the ST map when β → 0. For β ≠ 0 the relativity suppresses the onset of stochasticity. Chernikov et al. has also reported this effect. They have carried out extensive studies of nonlinear dynamics of the RST map and found very intricate structure of mixing of the higher order periodic orbits and chaotic orbits. They have shown that no matter how its gets chaotic the symmetry properties of the RST map determines its nonlinear dynamical behavior. 1 ref
General-relativistic pulsar magnetospheric emission
Pétri, J.
2018-06-01
Most current pulsar emission models assume photon production and emission within the magnetosphere. Low-frequency radiation is preferentially produced in the vicinity of the polar caps, whereas the high-energy tail is shifted to regions closer but still inside the light cylinder. We conducted a systematic study of the merit of several popular radiation sites like the polar cap, the outer gap, and the slot gap. We computed sky maps emanating from each emission site according to a prescribed distribution function for the emitting particles made of an electron/positron mixture. Calculations are performed using a three-dimensional integration of the plasma emissivity in the vacuum electromagnetic field of a rotating and centred general-relativistic dipole. We compare Newtonian electromagnetic fields to their general-relativistic counterpart. In the latter case, light bending is also taken into account. As a typical example, light curves and sky maps are plotted for several power-law indices of the particle distribution function. The detailed pulse profiles strongly depend on the underlying assumption about the fluid motion subject to strong electromagnetic fields. This electromagnetic topology enforces the photon propagation direction directly, or indirectly, from aberration effects. We also discuss the implication of a net stellar electric charge on to sky maps. Taking into account, the electric field strongly affects the light curves originating close to the light cylinder, where the electric field strength becomes comparable to the magnetic field strength.
An introduction to relativistic hydrodynamics
Energy Technology Data Exchange (ETDEWEB)
Font, Jose A [Departamento de AstronomIa y AstrofIsica, Universidad de Valencia, Dr. Moliner 50, 46100 Burjassot (Valencia) (Spain)
2007-11-15
We review formulations of the equations of (inviscid) general relativistic hydrodynamics and (ideal) magnetohydrodynamics, along with methods for their numerical solution. Both systems can be cast as first-order, hyperbolic systems of conservation laws, following the explicit choice of an Eulerian observer and suitable fluid and magnetic field variables. During the last fifteen years, the so-called (upwind) high-resolution shock-capturing schemes based on Riemann solvers have been successfully extended from classical to relativistic fluid dynamics, both special and general. Nowadays, general relativistic hydrodynamical simulations in relativistic astrophysics are routinely performed, particularly within the test-fluid approximation but also for dynamical spacetimes. While such advances also hold true in the case of the MHD equations, the astrophysical applications investigated so far are still limited, yet the field is bound to witness major developments in the near future. The article also presents a brief overview of numerical techniques, providing state-of-the-art examples of their applicability to general relativistic fluids and magneto-fluids in characteristic scenarios of relativistic astrophysics.
Radiation dominated relativistic current sheets
International Nuclear Information System (INIS)
Jaroschek, C.H.
2008-01-01
Relativistic Current Sheets (RCS) feature plasma instabilities considered as potential key to magnetic energy dissipation and non-thermal particle generation in Poynting flux dominated plasma flows. We show in a series of kinetic plasma simulations that the physical nature of non-linear RCS evolution changes in the presence of incoherent radiation losses: In the ultra-relativistic regime (i.e. magnetization parameter sigma = 104 defined as the ratio of magnetic to plasma rest frame energy density) the combination of non-linear RCS dynamics and synchrotron emission introduces a temperature anisotropy triggering the growth of the Relativistic Tearing Mode (RTM). As direct consequence the RTM prevails over the Relativistic Drift Kink (RDK) Mode as competitive RCS instability. This is in contrast to the previously studied situation of weakly relativistic RCS (sigma ∼ 1) where the RDK is dominant and most of the plasma is thermalized. The simulations witness the typical life cycle of ultra-relativistic RCS evolving from a violent radiation induced collapse towards a radiation quiescent state in rather classical Sweet-Parker topology. Such a transition towards Sweet-Parker configuration in the late non-linear evolution has immediate consequences for the efficiency of magnetic energy dissipation and non-thermal particle generation. Ceasing dissipation rates directly affect our present understanding of non-linear RCS evolution in conventional striped wind scenarios. (author)
Breakup of spectator residues in relativistic nuclear collisions
International Nuclear Information System (INIS)
Warwick, A.I.; Wieman, H.H.; Gutbrod, H.H.
1983-01-01
Low energy nuclear fragments (12 4 He, and 20 Ne projectiles are measured to yield information on the breakup of the target nucleus. We discuss the shapes of the fragment energy spectra across this broad range of fragment mass and pick out the fission component by its binary breakup. Multiplicities of coincident fast charged particles are presented as a measure of the degree of violence of the initial stage of the collision. Angular distributions of light fragments (8< or =Z< or =11) give the average velocities imparted to the residue in central collisions, and these values are compared to the results of cascade calculations. Measurements of slow fragment multiplicities from central events reveal a many-fragment final state. In the light of this finding we develop a simple calculation of the Coulomb features of the observed spectra. The applicability of a statistical breakup model is discussed
From laser cooling of non-relativistic to relativistic ion beams
International Nuclear Information System (INIS)
Schramm, U.; Bussmann, M.; Habs, D.
2004-01-01
Laser cooling of stored 24 Mg + ion beams recently led to the long anticipated experimental realization of Coulomb-ordered 'crystalline' ion beams in the low-energy RF-quadrupole storage ring PAul Laser CooLing Acceleration System (Munich). Moreover, systematic studies revealed severe constraints on the cooling scheme and the storage ring lattice for the attainment and maintenance of the crystalline state of the beam, which will be summarized. With the envisaged advent of high-energy heavy ion storage rings like SIS 300 at GSI (Darmstadt), which offer favourable lattice conditions for space-charge-dominated beams, we here discuss the general scaling of laser cooling of highly relativistic beams of highly charged ions and present a novel idea for direct three-dimensional beam cooling by forcing the ions onto a helical path
Energy Technology Data Exchange (ETDEWEB)
Rentenier, A; Bordenave-Montesquieu, D; Moretto-Capelle, P; Bordenave-Montesquieu, A [Laboratoire CAR-IRSAMC, UMR 5589 CNRS - Universite Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse Cedex (France)
2003-04-28
Multifragmentation and asymmetric fission (AF) of the C{sub 60} molecule induced by H{sup +}, H{sub 2}{sup +}, H{sub 3}{sup +} and He{sup +} ions at medium collision energies (2-130 keV) are considered. Momenta and kinetic energies of C{sub n}{sup +} fragment ions (n = 1- 12) are deduced from an analysis of time-of-flight spectra. In multifragmentation processes, momenta are found to be approximately constant when n > 2, a behaviour which explains that the most probable kinetic energy, as well as the width of the kinetic energy distributions, is found to be inversely proportional to the fragment size n; both momenta and kinetic energies are independent of the velocity and nature of the projectile, and hence of the energy deposit. A specific study of the AF shows that the kinetic energies of C{sub 2}{sup +}, C{sub 4}{sup +} and C{sub 6}{sup +} fragments are also independent of the collision velocity and projectile species; a quantitative agreement is found with values deduced from kinetic energy release measurements by another group in electron impact experiments, and the observed decrease when the mass of the light fragment increases is also reproduced. A quantitative comparison of AF and multifragmentation for the n = 2, 4 and 6 fragment ions shows that kinetic energies in AF exceed that in multifragmentation, a result which explains the oscillations observed when momenta or kinetic energies of fragments are plotted against the n-value. The AF yield is also found to scale with the energy deposit in the collision velocity range extending below the velocity at the maximum of the electronic stopping power; except for protons, it remains negligible with respect to multifragmentation as soon as the total energy deposit exceeds about 100 eV.
2002-01-01
The aim of the experiment is to measure the multiplicity ``$ n _{s} $'' and pseudo-rapidity ``$\\eta$'' of the shower particles ($\\beta$~$\\geq$~0.7) produced in different types of collisions (peripheral, semi-central and central), of $^{16}$O and $^{32}$S in nuclear emulsions. The multiplicities and angular distributions of both the grey ``$ n _{g} $'' (mainly due to knock- on and recoil protons), and black ``$ n _{b} $'' (slow evaporated target fragments) particles, and the inter-correlation between them are studied. \\\\ \\\\ The yield, charge and angular distributions of produced relativistic projectile fragments P.F.S., for $ Z _{P} . _{F} . $ $\\geq$~2 are measured and their interactions in emulsions are investigated. \\\\ \\\\ The study of the mean free paths for the projectile fragments with Z $\\geq$ 3 produced from 200~A~GeV $^{16}$ 0 interactions were performed, which show the absence of the anomalous phenomena. \\\\ \\\\ The possible production of zero-spin light neutral scaler bosons and pseudoscaler bosons from...
Linear waves in two-fluid relativistic gasdynamics
International Nuclear Information System (INIS)
Gavrikov, M.B.; Solov'ev, L.S.
1988-01-01
This paper is devoted to the development of a theory of waves propagating in a two-component gaseous medium. In all cases considered the authors use only the method of two-fluid relativistic electromagnetic gasdynamics in the framework of the special relativity theory. They pay special attention to the problem of the interaction in a mixture of both neutral and charged gases when they move relative to one another. This interaction is for charged gases responsible for the appearance of ohmic resistance to an electrical current
Coulomb-Driven Relativistic Electron Beam Compression
Lu, Chao; Jiang, Tao; Liu, Shengguang; Wang, Rui; Zhao, Lingrong; Zhu, Pengfei; Xiang, Dao; Zhang, Jie
2018-01-01
Coulomb interaction between charged particles is a well-known phenomenon in many areas of research. In general, the Coulomb repulsion force broadens the pulse width of an electron bunch and limits the temporal resolution of many scientific facilities such as ultrafast electron diffraction and x-ray free-electron lasers. Here we demonstrate a scheme that actually makes use of the Coulomb force to compress a relativistic electron beam. Furthermore, we show that the Coulomb-driven bunch compression process does not introduce additional timing jitter, which is in sharp contrast to the conventional radio-frequency buncher technique. Our work not only leads to enhanced temporal resolution in electron-beam-based ultrafast instruments that may provide new opportunities in probing material systems far from equilibrium, but also opens a promising direction for advanced beam manipulation through self-field interactions.
Coulomb-Driven Relativistic Electron Beam Compression.
Lu, Chao; Jiang, Tao; Liu, Shengguang; Wang, Rui; Zhao, Lingrong; Zhu, Pengfei; Xiang, Dao; Zhang, Jie
2018-01-26
Coulomb interaction between charged particles is a well-known phenomenon in many areas of research. In general, the Coulomb repulsion force broadens the pulse width of an electron bunch and limits the temporal resolution of many scientific facilities such as ultrafast electron diffraction and x-ray free-electron lasers. Here we demonstrate a scheme that actually makes use of the Coulomb force to compress a relativistic electron beam. Furthermore, we show that the Coulomb-driven bunch compression process does not introduce additional timing jitter, which is in sharp contrast to the conventional radio-frequency buncher technique. Our work not only leads to enhanced temporal resolution in electron-beam-based ultrafast instruments that may provide new opportunities in probing material systems far from equilibrium, but also opens a promising direction for advanced beam manipulation through self-field interactions.
New developments in relativistic klystron amplifiers
Energy Technology Data Exchange (ETDEWEB)
Friedman, M; Colombant, D; Fernsler, R; Hubbard, R; Lampe, M; Serlin, V; Slinker, S [Naval Research Lab., Washington, DC (United States). Plasma Physics Div.
1997-12-31
A relativistic klystron amplifier that employed cavities with inductively loaded wide gaps and a novel converter has achieved 50% energy efficiency, a significant advance over the previous state of the art of 20%. The new device was immersed in a 3 kG magnetic field and contained two innovations: (1) Wide gaps which include an inductively loaded return current structure that was opaque to the unmodulated beam space charge but transparent to the RF field. (2) A novel converter that was made of a `leaky` cavity with a radially-converging inductively-loaded structure that was inserted in the output wide-gap. This structure reduced the potential energy residing in the electron beam and maximized RF output energy. (author). 4 figs., 13 refs.
Relativistic quarkonium model with retardation effect, 1
International Nuclear Information System (INIS)
Ito, Hitoshi
1990-01-01
A new relativistic two-body equation is proposed which has the charge-conjugation symmetry. The renormalization of the wave function at the origin (WFO) is done by incorporating the corresponding vertex equation. By using this model, the heavy-quarkonium phenomenology is developed putting emphasis on the short-distance interaction. The typical scale of the distance restricting the applicability of the ladder model for the mass spectra is found to be 0.13 fm: By assuming the equivalent high-momentum cutoff for the gluonic correction, good results are obtained for the charmonium masses. The improved fine-splittings of the bb-bar states are obtained by inclusion of the retardation. Leptonic decay rates are predicted by assuming the renormalized WFO reduced by another high-momentum cutoff. (author)
Relativistic theory of gravitation
International Nuclear Information System (INIS)
Logunov, A.A.; Mestvirishvili, M.A.
1986-01-01
In the present paper a relativistic theory of gravitation (RTG) is unambiguously constructed on the basis of the special relativity and geometrization principle. In this a gravitational field is treated as the Faraday--Maxwell spin-2 and spin-0 physical field possessing energy and momentum. The source of a gravitational field is the total conserved energy-momentum tensor of matter and of a gravitational field in Minkowski space. In the RTG the conservation laws are strictly fulfilled for the energy-moment and for the angular momentum of matter and a gravitational field. The theory explains the whole available set of experiments on gravity. By virtue of the geometrization principle, the Riemannian space in our theory is of field origin, since it appears as an effective force space due to the action of a gravitational field on matter. The RTG leads to an exceptionally strong prediction: The universe is not closed but just ''flat.'' This suggests that in the universe a ''missing mass'' should exist in a form of matter
Relativistic theory of gravitation
International Nuclear Information System (INIS)
Logunov, A.A.; Mestvirishvilli, M.A.
1985-01-01
In the present paper a relativistic theory of gravitation (RTG) is constructed in a unique way on the basis of the special relativity and geometrization principle. In this, a gravitational field is treated as the Faraday-Maxwell spin-2 and spin-0 physical field possessing energy and momentum. The source of a gravitational field is the total conserved energy-momentum tensor of matter and of a gravitational field in Minkowski space. In the RTG, the conservation laws are strictly fulfilled for the energy-momentum and for the angular momentum of matter and a gravitational field. The theory explains the whole available set of experiments on gravitation. In virtue of the geometrization principle, the Riemannian space in our theory is of field origin, since it appears as an effective force space due to the action of a gravitational field on matter. The RTg leads to an exceptionally strong prediction: The Universe is not closed but just ''flat''. This suggests that in the Universe a ''hidden mass'' should exist in some form of matter
Relativistic gravitation theory
International Nuclear Information System (INIS)
Logunov, A.A.; Mestvirishvili, M.A.
1984-01-01
On the basis of the special relativity and geometrization principle a relativistic gravitation theory (RGT) is unambiguously constructed with the help of a notion of a gravitational field as a physical field in Faraday-Maxwell spirit, which posesses energy momentum and spins 2 and 0. The source of gravitation field is a total conserved energy-momentum tensor for matter and for gravitation field in Minkowski space. In the RGT conservation laws for the energy momentum and angular momentum of matter and gravitational field hold rigorously. The theory explains the whole set of gravitation experiments. Here, due to the geometrization principle the Riemannian space is of a field origin since this space arises effectively as a result of the gravitation field origin since this space arises effectively as a result of the gravitation field action on the matter. The RGT astonishing prediction is that the Universe is not closed but ''flat''. It means that in the Universe there should exist a ''missing'' mass in some form of matter
Laser-pulsed relativistic electron gun
International Nuclear Information System (INIS)
Sherman, N.K.
1986-01-01
A relativistic (β ≅ 0.8) electron gun with good emittance and subnanosecond pulse duration which can be synchronized to picosecond laser pulses is being developed at NRC for use in studies of particle acceleration by lasers. Bursts of electron pulses exceeding 280 keV in energy have been extracted into air form a laser-driven vacuum photodiode. Trains of 5 ps pulses of ultraviolet UV light illuminate a magnesium cathode. Photoelectrons emitted from the cathode are accelerated in a graded electrostatic potential set up by a 360 kV Marx-generator. The UV pulses are obtained by doubling the frequency of a 606 nm dye laser modelocked at 160 MHz. Electron energies were measured by residual range in an echelon of Al foils. Total charge per burst was measured by picoammeter. Time structure of the bursts has been examined with plastic scintillator and a fast photomultiplier. Tests on a low voltage photodiode achieved a current density of 180 A/cm/sup 2/ from an Mg cathode, with quantum efficiency of 2.4 x 10/sup -6/ electron per UV photon. The brevity and intensity of the laser pulses cause the electric charge collected per pulse to increase linearly with bias voltage rather than according to the Langmuir-Child law. Gun emittance is about 150 mm-msr and beam brightness is about 1A/cm/sup 2/-sr. Estimated duration of individual electron pulses of a burst is about 400 ps with instantaneous current of about 0.1 mA. Energy spread within one pulse is expected to be about 15%. This gun has the potential to be a useful source of relativistic electrons for laser acceleration studies
Relativistic positioning systems: perspectives and prospects
Coll Bartolomé
2013-11-01
Relativistic positioning systems are interesting technical objects for applications around the Earth and in the Solar system. But above all else, they are basic scientific objects allowing developing relativity from its own concepts. Some past and future features of relativistic positioning sys- tems, with special attention to the developments that they suggest for an epistemic relativity (relativistic experimental approach to physics), are analyzed. This includes relativistic stereometry, which, together with relativistic positioning systems, allows to introduce the general relativistic notion of (finite) laboratory (space-time region able to perform experiments of finite size).
OPE convergence in non-relativistic conformal field theories
Energy Technology Data Exchange (ETDEWEB)
Goldberger, Walter D.; Khandker, Zuhair University; Prabhu, Siddharth [Department of Physics, Yale University,New Haven, CT 06511 (United States); Physics Department, Boston University,Boston, MA 02215 (United States)
2015-12-09
Motivated by applications to the study of ultracold atomic gases near the unitarity limit, we investigate the structure of the operator product expansion (OPE) in non-relativistic conformal field theories (NRCFTs). The main tool used in our analysis is the representation theory of charged (i.e. non-zero particle number) operators in the NRCFT, in particular the mapping between operators and states in a non-relativistic “radial quantization” Hilbert space. Our results include: a determination of the OPE coefficients of descendant operators in terms of those of the underlying primary state, a demonstration of convergence of the (imaginary time) OPE in certain kinematic limits, and an estimate of the decay rate of the OPE tail inside matrix elements which, as in relativistic CFTs, depends exponentially on operator dimensions. To illustrate our results we consider several examples, including a strongly interacting field theory of bosons tuned to the unitarity limit, as well as a class of holographic models. Given the similarity with known statements about the OPE in SO(2,d) invariant field theories, our results suggest the existence of a bootstrap approach to constraining NRCFTs, with applications to bound state spectra and interactions. We briefly comment on a possible implementation of this non-relativistic conformal bootstrap program.
Relativistic theory of gravity
International Nuclear Information System (INIS)
Logunov, A.A.; Mestvirishvili, M.A.
1985-01-01
This work presents an unambiguous construction of the relativistic theory of gravity (RTG) in the framework of relativity and the geometrization principle. The gauge principle has been formulated, and the Lagrangian density of the gravitational field has thus been constructed. This theory explains the totality of the available experimental data on the solar system and predicts the existence of gravitational waves of the Faraday-Maxwell type. According to the RTG, the Universe is infinite and ''flat'', hence it follows that its matter density should be equal to its critical density. Therefore, an appreciable ''hidden mass'' exceeding the presently observed mass of the matter almost 40-fold should exist in the Universe in some form of the matter or other. In accordance with the RTG, a massive body having a finite density ceases to contract under gravitational forces within a finite interval of proper time. From the viewpoint of an external reference frame, the brightness of the body decreases exponentially (it is getting darker), but nothing extraordinary happens in this case because its density always remains finite and, for example, for a body with the mass of about 10 8 M 0 it is equal to 2 g/cm 3 . That is why it follows from the RTG that there could be no object whatsoever (black holes) in which gravitational collapse of matter develops to an infinite density. As has been shown, the presence of a cosmological term necessarily requires the introduction of a term with an explicit dependence on the Minkowski metrics. For the long-range gravitational forces the cosmological constant vanishes
Radiatively driven relativistic spherical winds under relativistic radiative transfer
Fukue, J.
2018-05-01
We numerically investigate radiatively driven relativistic spherical winds from the central luminous object with mass M and luminosity L* under Newtonian gravity, special relativity, and relativistic radiative transfer. We solve both the relativistic radiative transfer equation and the relativistic hydrodynamical equations for spherically symmetric flows under the double-iteration processes, to obtain the intensity and velocity fields simultaneously. We found that the momentum-driven winds with scattering are quickly accelerated near the central object to reach the terminal speed. The results of numerical solutions are roughly fitted by a relation of \\dot{m}=0.7(Γ _*-1)\\tau _* β _* β _out^{-2.6}, where \\dot{m} is the mass-loss rate normalized by the critical one, Γ* the central luminosity normalized by the critical one, τ* the typical optical depth, β* the initial flow speed at the central core of radius R*, and βout the terminal speed normalized by the speed of light. This relation is close to the non-relativistic analytical solution, \\dot{m} = 2(Γ _*-1)\\tau _* β _* β _out^{-2}, which can be re-expressed as β _out^2/2 = (Γ _*-1)GM/c^2 R_*. That is, the present solution with small optical depth is similar to that of the radiatively driven free outflow. Furthermore, we found that the normalized luminosity (Eddington parameter) must be larger than unity for the relativistic spherical wind to blow off with intermediate or small optical depth, i.e. Γ _* ≳ \\sqrt{(1+β _out)^3/(1-β _out)}. We briefly investigate and discuss an isothermal wind.
Scattering in relativistic particle mechanics
International Nuclear Information System (INIS)
De Bievre, S.
1986-01-01
The problem of direct interaction in relativistic particle mechanics has been extensively studied and a variety of models has been proposed avoiding the conclusions of the so-called no-interaction theorems. In this thesis the authors studied scattering in the relativistic two-body problem. He uses the results to analyze gauge invariance in Hamiltonian constraint models and the uniqueness of the symplectic structure in manifestly covariant relativistic particle mechanics. A general geometric framework that underlies approaches to relativistic particle mechanics is presented and the kinematic properties of the scattering transformation, i.e., those properties that arise solely from the invariance of the theory under the Poincare group are studied. The second part of the analysis of the relativistic two-body scattering problem is devoted to the dynamical properties of the scattering process. Using general geometric arguments, gauge invariance of the scattering transformation in the Todorov-Komar Hamiltonian constraint model is proved. Finally, quantization of the models is discussed
Universal elements of fragmentation
International Nuclear Information System (INIS)
Yanovsky, V. V.; Tur, A. V.; Kuklina, O. V.
2010-01-01
A fragmentation theory is proposed that explains the universal asymptotic behavior of the fragment-size distribution in the large-size range, based on simple physical principles. The basic principles of the theory are the total mass conservation in a fragmentation process and a balance condition for the energy expended in increasing the surface of fragments during their breakup. A flux-based approach is used that makes it possible to supplement the basic principles and develop a minimal theory of fragmentation. Such a supplementary principle is that of decreasing fragment-volume flux with increasing energy expended in fragmentation. It is shown that the behavior of the decreasing flux is directly related to the form of a power-law fragment-size distribution. The minimal theory is used to find universal asymptotic fragment-size distributions and to develop a natural physical classification of fragmentation models. A more general, nonlinear theory of strong fragmentation is also developed. It is demonstrated that solutions to a nonlinear kinetic equation consistent with both basic principles approach a universal asymptotic size distribution. Agreement between the predicted asymptotic fragment-size distributions and experimental observations is discussed.
Consideration of Relativistic Dynamics in High-Energy Electron Coolers
Bruhwiler, David L
2005-01-01
A proposed electron cooler for RHIC would use ~55 MeV electrons to cool fully-ionized 100 GeV/nucleon gold ions.* At two locations in the collider ring, the electrons and ions will co-propagate for ~13 m, with velocities close to c and gamma>100. To lowest-order, one can Lorentz transform all physical quantities into the beam frame and calculate the dynamical friction forces assuming a nonrelativisitc, electrostatic plasma. However, we show that nonlinear space charge forces of the bunched electron beam on the ions must be calculated relativistically, because an electrostatic beam-frame calculation is not valid for such short interaction times. The validity of nonrelativistic friction force calculations must also be considered. Further, the transverse thermal velocities of the high-charge (~20 nC) electron bunch are large enough that some electrons have marginally relativistic velocities, even in the beam frame. Hence, we consider relativistic binary collisions treating the model problem of ...
Heavy Flavor Fragmentation and Decay at SLD
Energy Technology Data Exchange (ETDEWEB)
Plano, Richard M
1999-02-24
Results on heavy quark fragmentation obtained using the SLD detector at the SLAC Linear Collider are presented. This talk will cover the ratio of vector to pseudoscalar charmed meson production, the inclusive B hadron energy distribution, the inclusive particle production in heavy jets compared to their production in light jets, and charged and neutral B meson lifetimes.
Cooling rates and intensity limitations for laser-cooled ions at relativistic energies
Eidam, Lewin; Boine-Frankenheim, Oliver; Winters, Danyal
2018-04-01
The ability of laser cooling for relativistic ion beams is investigated. For this purpose, the excitation of relativistic ions with a continuous wave and a pulsed laser is analyzed, utilizing the optical Bloch equations. The laser cooling force is derived in detail and its scaling with the relativistic factor γ is discussed. The cooling processes with a continuous wave and a pulsed laser system are investigated. Optimized cooling scenarios and times are obtained in order to determine the required properties of the laser and the ion beam for the planed experiments. The impact of beam intensity effects, like intrabeam scattering and space charge are analyzed. Predictions from simplified models are compared to particle-in-cell simulations and are found to be in good agreement. Finally two realistic example cases of Carbon ions in the ESR and relativistic Titanium ions in SIS100 are compared in order to discuss prospects for future laser cooling experiments.
The incompressible non-relativistic Navier-Stokes equation from gravity
International Nuclear Information System (INIS)
Bhattacharyya, Sayantani; Minwalla, Shiraz; Wadia, Spenta R.
2009-01-01
We note that the equations of relativistic hydrodynamics reduce to the incompressible Navier-Stokes equations in a particular scaling limit. In this limit boundary metric fluctuations of the underlying relativistic system turn into a forcing function identical to the action of a background electromagnetic field on the effectively charged fluid. We demonstrate that special conformal symmetries of the parent relativistic theory descend to 'accelerated boost' symmetries of the Navier-Stokes equations, uncovering a conformal symmetry structure of these equations. Applying our scaling limit to holographically induced fluid dynamics, we find gravity dual descriptions of an arbitrary solution of the forced non-relativistic incompressible Navier-Stokes equations. In the holographic context we also find a simple forced steady state shear solution to the Navier-Stokes equations, and demonstrate that this solution turns unstable at high enough Reynolds numbers, indicating a possible eventual transition to turbulence.
Relativistic electron Wigner crystal formation in a cavity for electron acceleration
Thomas, Johannes; Pukhov, Alexander
2014-01-01
It is known that a gas of electrons in a uniform neutralizing background can crystallize and form a lattice if the electron density is less than a critical value. This crystallization may have two- or three-dimensional structure. Since the wake field potential in the highly-nonlinear-broken-wave regime (bubble regime) has the form of a cavity where the background electrons are evacuated from and only the positively charged ions remain, it is suited for crystallization of trapped and accelerated electron bunch. However, in this case, the crystal is moving relativistically and shows new three-dimensional structures that we call relativistic Wigner crystals. We analyze these structures using a relativistic Hamiltonian approach. We also check for stability and phase transitions of the relativistic Wigner crystals.
Theoretical study of relativistic effects in the electronic structure and chemical bonding of UF6
International Nuclear Information System (INIS)
Onoe, Jun; Takeuchi, Kazuo; Sekine, Rika; Nakamatsu, Hirohide; Mukoyama, Takeshi; Adachi, Hirohiko.
1992-01-01
We have performed the relativistic molecular orbital calculation for the ground state of UF 6 , using the discrete-variational Dirac-Slater method (DV-DS), in order to elucidate the relativistic effects in the electronic structure and chemical bonding. Compared with the electronic structure calculated by the non-relativistic Hartree-Fock-Slater (DV-X α )MO method, not only the direct relativistic effects (spin-orbit splitting etc), but also the indirect effect due to the change in screening core potential charge are shown to be important in the MO level structure. From the U-F bond overlap population analysis, we found that the U-F bond formation can be explained only by the DV-DS, not by the DV-X α . The calculated electronic structure in valence energy region (-20-OeV) and excitation energies in UV region are in agreement with experiments. (author)
International Nuclear Information System (INIS)
Nottale, Laurent
2003-01-01
The principle of relativity, when it is applied to scale transformations, leads to the suggestion of a generalization of fundamental dilations laws. These new special scale-relativistic resolution transformations involve log-Lorentz factors and lead to the occurrence of a minimal and of a maximal length-scale in nature, which are invariant under dilations. The minimal length-scale, that replaces the zero from the viewpoint of its physical properties, is identified with the Planck length l P , and the maximal scale, that replaces infinity, is identified with the cosmic scale L=Λ -1/2 , where Λ is the cosmological constant.The new interpretation of the Planck scale has several implications for the structure and history of the early Universe: we consider the questions of the origin, of the status of physical laws at very early times, of the horizon/causality problem and of fluctuations at recombination epoch.The new interpretation of the cosmic scale has consequences for our knowledge of the present universe, concerning in particular Mach's principle, the large number coincidence, the problem of the vacuum energy density, the nature and the value of the cosmological constant. The value (theoretically predicted ten years ago) of the scaled cosmological constant Ω Λ =0.75+/-0.15 is now supported by several different experiments (Hubble diagram of Supernovae, Boomerang measurements, gravitational lensing by clusters of galaxies).The scale-relativity framework also allows one to suggest a solution to the missing mass problem, and to make theoretical predictions of fundamental energy scales, thanks to the interpretation of new structures in scale space: fractal/classical transitions as Compton lengths, mass-coupling relations and critical value 4π 2 of inverse couplings. Among them, we find a structure at 3.27+/-0.26x10 20 eV, which agrees closely with the observed highest energy cosmic rays at 3.2+/-0.9x10 20 eV, and another at 5.3x10 -3 eV, which corresponds to the
SPECIAL RELATIVISTIC HYDRODYNAMICS WITH GRAVITATION
Energy Technology Data Exchange (ETDEWEB)
Hwang, Jai-chan [Department of Astronomy and Atmospheric Sciences, Kyungpook National University, Daegu (Korea, Republic of); Noh, Hyerim [Korea Astronomy and Space Science Institute, Daejon (Korea, Republic of)
2016-12-20
Special relativistic hydrodynamics with weak gravity has hitherto been unknown in the literature. Whether such an asymmetric combination is possible has been unclear. Here, the hydrodynamic equations with Poisson-type gravity, considering fully relativistic velocity and pressure under the weak gravity and the action-at-a-distance limit, are consistently derived from Einstein’s theory of general relativity. An analysis is made in the maximal slicing, where the Poisson’s equation becomes much simpler than our previous study in the zero-shear gauge. Also presented is the hydrodynamic equations in the first post-Newtonian approximation, now under the general hypersurface condition. Our formulation includes the anisotropic stress.
Methods in relativistic nuclear physics
International Nuclear Information System (INIS)
Danos, M.; Gillet, V.; Cauvin, M.
1984-01-01
This book is intended to provide the methods and tools for performing actual calculations for finite many-body systems of bound relativistic constituent particles. The aim is to cover thoroughly the methodological aspects of the relativistic many-body problem for bound states while avoiding the presentation of specific models. The many examples contained in the later part of the work are meant to give concrete illustrations of how to actually apply the methods which are given in the first part. The basic framework of the approach is the lagrangian field theory solved in the time-independent Schroedinger picture. (Auth.)
Frontiers in relativistic celestial mechanics
2014-01-01
Relativistic celestial mechanics – investigating the motion celestial bodies under the influence of general relativity – is a major tool of modern experimental gravitational physics. With a wide range of prominent authors from the field, this two-volume series consists of reviews on a multitude of advanced topics in the area of relativistic celestial mechanics – starting from more classical topics such as the regime of asymptotically-flat spacetime, light propagation and celestial ephemerides, but also including its role in cosmology and alternative theories of gravity as well as modern experiments in this area.
Directory of Open Access Journals (Sweden)
Richard Anantua
2018-03-01
Full Text Available This work summarizes a program intended to unify three burgeoning branches of the high-energy astrophysics of relativistic jets: general relativistic magnetohydrodynamic (GRMHD simulations of ever-increasing dynamical range, the microphysical theory of particle acceleration under relativistic conditions, and multiwavelength observations resolving ever-decreasing spatiotemporal scales. The process, which involves converting simulation output into time series of images and polarization maps that can be directly compared to observations, is performed by (1 self-consistently prescribing models for emission, absorption, and particle acceleration and (2 performing time-dependent polarized radiative transfer. M87 serves as an exemplary prototype for this investigation due to its prominent and well-studied jet and the imminent prospect of learning much more from Event Horizon Telescope (EHT observations this year. Synthetic observations can be directly compared with real observations for observational signatures such as jet instabilities, collimation, relativistic beaming, and polarization. The simplest models described adopt the standard equipartition hypothesis; other models calculate emission by relating it to current density or shear. These models are intended for application to the radio jet instead of the higher frequency emission, the disk and the wind, which will be subjects of future investigations.
Apparent unambiguousness of relativistic time dilation
International Nuclear Information System (INIS)
Strel'tsov, V.N.
1992-01-01
It is indicated on the definite analogy between the dependence of visible sizes of relativistic objects and period of the wave, emitted by the moving source from the observation conditions ('retradition factor'). It is noted that the definition of time for moving extended objects, led to relativistic dilation, corresponds to the definition of the relativistic (radar) length led to the 'elongation formula'. 10 refs
Relativistic generalization of strong plasma turbulence
International Nuclear Information System (INIS)
Chian, A.C.-L.
1982-01-01
Two fundamental electrostatic modes of an unmagnetized plasma, namely, ion acoustic mode and Langumir mode are studied. Previous theories are generalized to include the effect of relativistic mass variations. The existence of relativistic ion acoustic solitons is demonstrated. In addition, it is shown that simple, relativistic Langumir solitons do not exist in a infinite plasma. (L.C.) [pt
Quantum gates via relativistic remote control
Energy Technology Data Exchange (ETDEWEB)
Martín-Martínez, Eduardo, E-mail: emartinm@uwaterloo.ca [Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada); Dept. Applied Math., University of Waterloo, Ontario, N2L 3G1 (Canada); Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5 (Canada); Sutherland, Chris [Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada)
2014-12-12
We harness relativistic effects to gain quantum control on a stationary qubit in an optical cavity by controlling the non-inertial motion of a different probe atom. Furthermore, we show that by considering relativistic trajectories of the probe, we enhance the efficiency of the quantum control. We explore the possible use of these relativistic techniques to build 1-qubit quantum gates.
Energy Technology Data Exchange (ETDEWEB)
Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2017-04-15
It is generally accepted that in order to describe the dynamics of relativistic particles in the laboratory (lab) frame it is sufficient to take into account the relativistic dependence of the particle momenta on the velocity. This solution of the dynamics problem in the lab frame makes no reference to Lorentz transformations. For this reason they are not discussed in particle tracking calculations in accelerator and plasma physics. It is generally believed that the electrodynamics problem can be treated within the same ''single inertial frame'' description without reference to Lorentz transformations. In particular, in order to evaluate radiation fields arising from charged particles in motion we need to know their velocities and positions as a function of the lab frame time t. The relativistic motion of a particle in the lab frame is described by Newton's second law ''corrected'' for the relativistic dependence of momentum on velocity. It is assumed in all standard derivations that one can perform identification of the trajectories in the source part of the usual Maxwell's equations with the trajectories vector x(t) measured (or calculated by using the corrected Newton's second law) in the lab frame. This way of coupling fields and particles is considered since more than a century as the relativistically correct procedure.We argue that this procedure needs to be changed, and we demonstrate the following, completely counterintuitive statement: the results of conventional theory of radiation by relativistically moving charges are not consistent with the principle of relativity. In order to find the trajectory of a particle in the lab frame consistent with the usual Maxwell's equations, one needs to solve the dynamic equation inmanifestly covariant form by using the coordinate-independent proper time τ to parameterize the particle world-line in space-time. We show that there is a difference between &apos
Fundamentals of relativistic particle beam optics
International Nuclear Information System (INIS)
Cornacchia, M.
1995-12-01
This lecture introduces the nonaccelerator-specialist to the motion of charged particles in a Storage Ring. The topics of discussion are restricted to the linear and nonlinear dynamics of a single particle in the transverse plane, i.e., the plane perpendicular to the direction of motion. The major omissions for a complete review of accelerator theory, for which a considerable literature exists, are the energy and phase oscillations (1). Other important accelerator physics aspects not treated here are the collective instabilities (2), the role of synchrotron radiation in electron storage rings (3), scattering processes (4), and beam-beam effects in colliding beam facilities (5). Much of the discussion that follows applies equally well to relativistic electron, proton, or ion synchrotrons. In this narrative, we refer to the particle as electron. After a broad overview, the magnetic forces acting on the electrons and the associated differential equations of motion are discussed. Solutions of the equations are given without derivation; the method of solution is outlined. and references for deeper studies are given. In this paper, the word electron is used to signify electron or positron. The dynamics of a single particle are not affected by the sign of its charge when the magnetic field direction is changed accordingly
Correlation function and electronic spectral line broadening in relativistic plasmas
Directory of Open Access Journals (Sweden)
Douis S.
2013-01-01
Full Text Available The electrons dynamics and the time autocorrelation function Cee(t for the total electric microfield of the electrons on positive charge impurity embedded in a plasma are considered when the relativistic dynamic of the electrons is taken into account. We have, at first, built the effective potential governing the electrons dynamics. This potential obeys a nonlinear integral equation that we have solved numerically. Regarding the electron broadening of the line in plasma, we have found that when the plasma parameters change, the amplitude of the collision operator changes in the same way as the time integral of Cee(t. The electron-impurity interaction is taken at first time as screened Deutsh interaction and at the second time as Kelbg interaction. Comparisons of all interesting quantities are made with respect to the previous interactions as well as between classical and relativistic dynamics of electrons.
Electron correlation within the relativistic no-pair approximation
DEFF Research Database (Denmark)
Almoukhalalati, Adel; Knecht, Stefan; Jensen, Hans Jørgen Aa
2016-01-01
and that this is possible by full Multiconfigurational Self-Consistent Field (MCSCF) calculations, that is, MCSCF calculations using a no-pair full CI expansion, but including orbital relaxation from the negative-energy orbitals. We show by variational perturbation theory that the MCSCF correlation energy is a pure MP2....... The well-known 1/Z- expansion in nonrelativistic atomic theory follows from coordinate scaling. We point out that coordinate scaling for consistency should be accompanied by velocity scaling. In the nonrelativistic domain this comes about automatically, whereas in the relativistic domain an explicit...... scaling of the speed of light is required. This in turn explains why the relativistic correlation energy to the lowest order is not independent of nuclear charge, in contrast to nonrelativistic theory....
Laser vacuum acceleration of a relativistic electron bunch
Energy Technology Data Exchange (ETDEWEB)
Glazyrin, I V; Karpeev, A V; Kotova, O G; Nazarov, K S [E.I. Zababakhin All-Russian Scientific-Research Institute of Technical Physics, Russian Federal Nuclear Centre, Snezhinsk, Chelyabinsk region (Russian Federation); Bychenkov, V Yu [P N Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)
2015-06-30
With regard to the problem of laser acceleration of a relativistic electron bunch we present a scheme of its vacuum acceleration directly by a relativistic intensity laser pulse. The energy of the electron bunch injected into the laser pulse leading edge increases during its coaxial movement to a thin, pulse-reflecting target. The laser-accelerated electrons continue to move free forward, passing through the target. The study of this acceleration scheme in the three-dimensional geometry is verified in a numerical simulation by the particle-in-cell method, which showed that the energy of a part of the electrons can increase significantly compared to the initial one. Restrictions are discussed, which impose limiting values of energy and total charge of accelerated electrons. (superstrong light fields)
Parton fragmentation and string dynamics
International Nuclear Information System (INIS)
Andersson, B.; Gustafson, G.; Ingelman, G.; Sjoestrand, T.
1983-01-01
While much has been learned recently about quark and gluon interactions in the framework of perturbative Quantum Chromodynamics, the relation between calculated parton properties and observed hadron densities involves models where dynamics and jet empirical rules have to be combined. The purpose of this article is to describe a presently successful approach which is based on a cascade jet model using String dynamics. It can readily lead to Monte Carlo jet programmes of great use when analyzing data. Production processes in an iterative cascade approach, with tunneling in a constant force field, are reviewed. Expected differences between quark and gluon jets are discussed. Low transverse momentum phenomena are also reviewed with emphasis on hyperon polarization. In so far as this approach uses a fragmentation scheme based on String dynamics, it was deemed appropriate to also include under the same cover a special report on the Classical theory of relativistic Strings, seen as the classical limit of the Dual Resonance model. The Equations of motion and interaction among strings are presented. (orig.)
Intermittency in {sup 197}Au fragmentation
Energy Technology Data Exchange (ETDEWEB)
Dabrowska, A; Holynski, R; Olszewski, A; Szarska, M; Wilczynska, B; Wolter, W; Wosiek, B [Institute of Nuclear Physics, Cracow (Poland); Cherry, M L; Deines-Jones, P; Jones, W V; Sengupta, K; Wefel, B [Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Physics and Astronomy; Waddington, C J [Minnesota Univ., Minneapolis, MN (United States). School of Physics and Astronomy; Pozharova, E A; Skorodko, T Yu [Inst. of Theoretical and Experimental Physics, Moscow (Russian Federation); KLMM Collaboration
1995-07-01
The concept of factorial moments was applied to an analysis of the dynamical fluctuations in the charge distributions of the fragments emitted from gold nuclei with energies 10.6 and < 1.0 GeV/n interacting with emulsion nuclei. Clear evidence for intermittent fluctuations has been found in an analysis using all the particles released from the gold projectile, with a stronger effect observed below 1 GeV/n than at 10.6 GeV/n. For the full data sets, however, the intermittency effect was found to be very sensitive to the singly charged particles, and neglecting these particles strongly reduces the intermittency signal. When the analysis is restricted to the multiply charged fragments, an intermittency effect is revealed only for multifragmentation events, although one that is enhanced as compared to the analysis of all, singly and multiply charged, particles. The properties of the anomalous fractal dimensions suggest a sequential decay mechanism, rather than the existence of possible critical behaviour in the process of nuclear fragmentation. The likely influence of the charge conservation effects and the finite size of decaying systems on the observed intermittency signals was pointed out. (author). 37 refs, 9 figs, 5 tabs.
Fragmentation and mean kinetic energy release of the nitrogen molecule
International Nuclear Information System (INIS)
Santos, A.C.F.; Melo, W.S.; Sant'Anna, M.M.; Sigaud, G.M.; Montenegro, E.C.
2007-01-01
Ionization and fragmentation of the N 2 molecule in coincidence with the final projectile charge state have been measured for the impact of 0.188-0.875 MeV/amu He + projectiles. The average kinetic energy release (KER) of the target ionic fragments is derived from the peak widths of their time-of-flight distributions. It is shown that the KER's for singly-charged products follow scaling laws irrespectively to the collision channel
Momentum distributions in nuclei measured with relativistic heavy ions
International Nuclear Information System (INIS)
Hiller, B.; Huefner, J.; Heidelberg Univ.
1982-01-01
In a peripheral reaction between relativistic heavy ions, where one nucleon is knocked out of the projektile, the momentum distribution of the remaining fragment reflects the momentum distribution of the knocked out nucleon. This has been proven in a previous paper. Here we study how the final-state interaction between the knocked out nucleon and the observed fragment influences the result: The real part of the optical potential which describes the final-state interaction shifts the experimental momentum distribution by a value [ksub(||)] of a few tens of MeV/c and the imaginary part reduces the cross sections by a factor 2 roughly. We also derive the cross section for a proton as target. (orig.)
Observation for really cold fragmentation of heavy nucleus
International Nuclear Information System (INIS)
Goverdovskij, A.A.; Ketlerov, V.V.; Mitrofanov, V.F.; Ostapenko, Yu.B.; Khryachkov, V.A.
1998-01-01
The results of the detailed study on mass-energy charged correlations of the thorium-232 fission fragments, produced by the 5 MeV neutrons are presented. The event of the thorium nucleus really cold fragmentation into tellurium-134 and strontium-99 at the basic quantum states is identified. It is shown that the whole reaction energy is exhausted by the motion kinetic energy of the fragments in the mutual field
Charge conjugation and internal space time symmetries
International Nuclear Information System (INIS)
Pavsic, M.; Recami, E.
1982-01-01
The relativistic framework in which fundamental particles are regarded as extended objects is adopted. Then it is shown than the geometrical operation which reflects the internal space time particle is equivalent to the operation C which inverts the sign of all its additive charges
Charge exchange in ion-atom collisions
International Nuclear Information System (INIS)
Bransden, B.H.
1990-01-01
Charge exchange reactions in which electrons are transferred from one ion (or atom) to another during a collision have been studied both as interesting examples of rearrangement collisions and because of important applications in plasma physics. This article reviews the modern theory developed for use at non-relativistic energies, but excluding the thermal and very low energy region. (author)
Improved description of the fragmentation of nuclear collective states
International Nuclear Information System (INIS)
Soloviev, V.G.
1984-01-01
A mathematical method is deveioped for a more accurate description of the fragmentation of one-phonon states forming giant resonances. The method consists in that the one-phonon states already fragmented are used in the two-phonon terms of wave functions. Strength functions are obtained for the exci excitation of collective charge-exchange states ano giant resonances in spherical nuclei
Next-To-Leading Order Determination of Fragmentation Functions
Bourhis, L; Guillet, J P; Werlen, M
2001-01-01
We analyse LEP and PETRA data on single inclusive charged hadron cross-sections to establish new sets of Next-to-Leading order Fragmentation Functions. Data on hadro-production of large-$p_{\\bot}$ hadrons are also used to constrain the gluon Fragmentation Function. We carry out a critical comparison with other NLO parametrizations.
Instability in relativistic nuclear matter
International Nuclear Information System (INIS)
Tezuka, Hirokazu.
1979-11-01
The stability of the Fermi gas state in the nuclear matter which satisfies the saturation property is considered relativistically. It is shown that the Fermi gas state is stable at very low density and at high density, but it is unstable for density fluctuation in the intermediate density region including the normal density. (author)
Cyberinfrastructure for Computational Relativistic Astrophysics
Ott, Christian
2012-01-01
Poster presented at the NSF Office of Cyberinfrastructure CyberBridges CAREER PI workshop. This poster discusses the computational challenges involved in the modeling of complex relativistic astrophysical systems. The Einstein Toolkit is introduced. It is an open-source community infrastructure for numerical relativity and computational astrophysics.
Future relativistic heavy ion experiments
International Nuclear Information System (INIS)
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
A relativistic radiation transfer benchmark
International Nuclear Information System (INIS)
Munier, A.
1988-01-01
We use the integral form of the radiation transfer equation in an one dimensional slab to determine the time-dependent propagation of the radiation energy, flux and pressure in a collisionless homogeneous medium. First order v/c relativistic terms are included and the solution is given in the fluid frame and the laboratory frame
Relativistic models of nuclear structure
International Nuclear Information System (INIS)
Gillet, V.; Kim, E.J.; Cauvin, M.; Kohmura, T.; Ohnaka, S.
1991-01-01
The introduction of the relativistic field formalism for the description of nuclear structure has improved our understanding of fundamental nuclear mechanisms such as saturation or many body forces. We discuss some of these progresses, both in the semi-classical mean field approximation and in a quantized meson field approach. (author)
Fundamental length and relativistic length
International Nuclear Information System (INIS)
Strel'tsov, V.N.
1988-01-01
It si noted that the introduction of fundamental length contradicts the conventional representations concerning the contraction of the longitudinal size of fast-moving objects. The use of the concept of relativistic length and the following ''elongation formula'' permits one to solve this problem
Universality of fragment shapes.
Domokos, Gábor; Kun, Ferenc; Sipos, András Árpád; Szabó, Tímea
2015-03-16
The shape of fragments generated by the breakup of solids is central to a wide variety of problems ranging from the geomorphic evolution of boulders to the accumulation of space debris orbiting Earth. Although the statistics of the mass of fragments has been found to show a universal scaling behavior, the comprehensive characterization of fragment shapes still remained a fundamental challenge. We performed a thorough experimental study of the problem fragmenting various types of materials by slowly proceeding weathering and by rapid breakup due to explosion and hammering. We demonstrate that the shape of fragments obeys an astonishing universality having the same generic evolution with the fragment size irrespective of materials details and loading conditions. There exists a cutoff size below which fragments have an isotropic shape, however, as the size increases an exponential convergence is obtained to a unique elongated form. We show that a discrete stochastic model of fragmentation reproduces both the size and shape of fragments tuning only a single parameter which strengthens the general validity of the scaling laws. The dependence of the probability of the crack plan orientation on the linear extension of fragments proved to be essential for the shape selection mechanism.
Fragmentation in DNA double-strand breaks
International Nuclear Information System (INIS)
Wei Zhiyong; Suzhou Univ., Suzhou; Zhang Lihui; Li Ming; Fan Wo; Xu Yujie
2005-01-01
DNA double strand breaks are important lesions induced by irradiations. Random breakage model or quantification supported by this concept is suitable to analyze DNA double strand break data induced by low LET radiation, but deviation from random breakage model is more evident in high LET radiation data analysis. In this work we develop a new method, statistical fragmentation model, to analyze the fragmentation process of DNA double strand breaks. After charged particles enter the biological cell, they produce ionizations along their tracks, and transfer their energies to the cells and break the cellular DNA strands into fragments. The probable distribution of the fragments is obtained under the condition in which the entropy is maximum. Under the approximation E≅E 0 + E 1 l + E 2 l 2 , the distribution functions are obtained as exp(αl + βl 2 ). There are two components, the one proportional to exp(βl 2 ), mainly contributes to the low mass fragment yields, the other component, proportional to exp(αl), decreases slowly as the mass of the fragments increases. Numerical solution of the constraint equations provides parameters α and β. Experimental data, especially when the energy deposition is higher, support the statistical fragmentation model. (authors)
Scaling of charged particle multiplicity distributions in relativistic nuclear collisions
International Nuclear Information System (INIS)
Ahamd, N.; Hushnud; Azmi, M.D.; Zafar, M.; Irfan, M.; Khan, M.M.; Tufail, A.
2011-01-01
Validity of KNO scaling in hadron-hadron and hadron-nucleus collisions has been tested by several workers. Multiplicity distributions for p-emulsion interactions are found to be consistent with the KNO scaling hypothesis for pp collisions. The applicability of the scaling law was extended to FNAL energies by earlier workers. Slattery has shown that KNO scaling hypothesis is in fine agreement with the data for pp interactions over a wide range of incident energies. An attempt, is, therefore, made to examine the scaling hypothesis using multiplicity distributions of particles produced in 3.7A GeV/c 16 O-, 4.5A GeV/c and 14.5A GeV/c 28 Si - nucleus interactions
Relativistic Descriptions of Few-Body Systems
International Nuclear Information System (INIS)
Karmanov, V. A.
2011-01-01
A brief review of relativistic effects in few-body systems, of theoretical approaches, recent developments and applications is given. Manifestations of relativistic effects in the binding energies, in the electromagnetic form factors and in three-body observables are demonstrated. The three-body forces of relativistic origin are also discussed. We conclude that relativistic effects in nuclei can be important in spite of small binding energy. At high momenta they clearly manifest themselves and are necessary to describe the deuteron e.m. form factors. At the same time, there is still a discrepancy in three-body observables which might be a result of less clarity in understanding the corresponding relativistic effects, the relativistic NN kernel and the three-body forces. Relativistic few-body physics remains to be a field of very intensive and fruitful researches. (author)
International Nuclear Information System (INIS)
Karmanov, V.A.
1983-01-01
Experimental data are given, the status of anomalon problem is discussed, theoretical approaches to this problem are outlined. Anomalons are exotic objects formed following fragmentation of nuclei-targets under the effect of nuclei - a beam at the energy of several GeV/nucleon. These nuclear fragments have an anomalously large cross section of interaction and respectively, small free path, considerably shorter than primary nuclei have. The experimental daa are obtained in accelerators following irradiation of nuclear emulsions by 16 O, 56 Fe, 40 Ar beams, as well as propane by 12 C beams. The experimental data testify to dependence of fragment free path on the distance L from the point of the fragment formation. A decrease in the fragment free path is established more reliably than its dependence on L. The problem of the anomalon existence cannot be yet considered resolved. Theoretical models suggested for explanation of anomalously large cross sections of nuclear fragment interaction are variable and rather speculative
Recent development of relativistic molecular theory
International Nuclear Information System (INIS)
Takahito, Nakajima; Kimihiko, Hirao
2005-01-01
Today it is common knowledge that relativistic effects are important in the heavy-element chemistry. The continuing development of the relativistic molecular theory is opening up rows of the periodic table that are impossible to treat with the non-relativistic approach. The most straightforward way to treat relativistic effects on heavy-element systems is to use the four-component Dirac-Hartree-Fock approach and its electron-correlation methods based on the Dirac-Coulomb(-Breit) Hamiltonian. The Dirac-Hartree-Fock (DHF) or Dirac-Kohn-Sham (DKS) equation with the four-component spinors composed of the large- and small-components demands severe computational efforts to solve, and its applications to molecules including heavy elements have been limited to small- to medium-size systems. Recently, we have developed a very efficient algorithm for the four-component DHF and DKS approaches. As an alternative approach, several quasi-relativistic approximations have also been proposed instead of explicitly solving the four-component relativistic equation. We have developed the relativistic elimination of small components (RESC) and higher-order Douglas-Kroll (DK) Hamiltonians within the framework of the two-component quasi-relativistic approach. The developing four-component relativistic and approximate quasi-relativistic methods have been implemented into a program suite named REL4D. In this article, we will introduce the efficient relativistic molecular theories to treat heavy-atomic molecular systems accurately via the four-component relativistic and the two-component quasi-relativistic approaches. We will also show several chemical applications including heavy-element systems with our relativistic molecular approaches. (author)
Effective stopping of relativistic structural heavy ions at collisions with atoms
International Nuclear Information System (INIS)
Matveev, V.I.
2002-01-01
One develops the unperturbed theory of energy losses at collision of atoms with structural high-charged heavy ions moving with relativistic velocity. One derived a simple formula for efficient braking. The structural ions in terms of this paper are considered to mean partially ionized ions of heavy elements compressing ion nucleus and some bound electrons compensating partially for ion nucleus charge. Account of ion charge magnitude is determined to result in essential increase of efficient braking of ion in contrast to braking of point nucleus of Z* charge [ru
Lepton-pair production by bremsstrahlung in central relativistic heavy ion collisions
International Nuclear Information System (INIS)
Lippert, T.; Becker, U.; Gruen, N.; Scheid, W.; Soff, G.
1988-03-01
We study the production of lepton-pairs by classical bremsstrahlung in central relativistic heavy-ion collisions. For the stopping of the nuclei we assume a simple model of point charges and a deceleration time. Pair creation probabilities are calculated in first order perturbation theory. (orig.)
Three-parameter relativistic dynamics. 1. Equation of motion, energy conservation
International Nuclear Information System (INIS)
Rogachevskii, A.G.
1995-01-01
A formally geometric analog of the relativistic dynamics of a point charged particle is constructed. Time as a function of the spatial coordinates is taken as the trajectory equation, i.e., the trajectory is a hypersurface in Minkowski space. The dynamics is presented. The law of open-quotes energyclose quotes conservation is examined
Relativistic Equations for Spin Particles: What can We Learn from Noncommutativity?
International Nuclear Information System (INIS)
Dvoeglazov, V. V.
2009-01-01
We derive relativistic equations for charged and neutral spin particles. The approach for higher-spin particles is based on generalizations of the Bargmann-Wigner formalism. Next, we study, what new physical information can give the introduction of non-commutativity. Additional non-commutative parameters can provide a suitable basis for explanation of the origin of mass.
Relativistic electron beam source with an air-core step-up transformer
International Nuclear Information System (INIS)
Mohri, Akihiro; Ikuta, Kazunari; Masuzaki, Masaru; Tsuzuki, Tetsuya; Fujiwaka, Setsuya.
1975-04-01
An air-core step-up transformer with a high coupling factor has been developed to generate a high voltage pulse for charging the pulse forming line of a relativistic electron beam source. A beam source using the transformer was constructed and well operated for the beam injection into a toroidal system. (auth.)
International Nuclear Information System (INIS)
Lee, E.P.
1977-01-01
In a recent report (UCID 17346, ''Relativistic Particle Beam in a Semi-Infinite Axially Symmetric conducting channel extending from a perfectly conducting plane,'' Dec. 13, 1976) Cooper and Neil demonstrate that the net charge transported by a beam pulse injected into a channel of finite conductivity equals the charge of the beam itself. The channel is taken to be infinite in the positive z direction, has finite radius and is terminated by a conducting ground plane at z =0. This result is not an obvious one, and it is restricted in its applicability by the special model assumed for the channel. It is the purpose to explain the result of Cooper and Neil in more qualitative terms and to make similar calculations using several other channel models. It must be emphasized that these calculations are not concerned with the fate of the transported charge after the pulse has stopped, but rather with how much charge leaves the ground plane assuming the pulse does not stop
Relativistic heavy ion research
International Nuclear Information System (INIS)
1992-01-01
Experimental work is reported on the following topics: transverse energy production in 10.7-GeV/c/u Au on Au collisions; first results on delta ray production and charged particle multiplicities with the Au beam at 10.7 GeV/c/A; preliminary studies on the feasibility of flow measurement with the E814 participant calorimeter; preliminary results from the E877 telescope; and low-p t baryon distribution in Si+Al, Pb collisions at the AGS. Then the status of the Hadronic Calorimeter project of AGS Experiment E864 (ECOS--Exotic Composite Object Spectrometer) is reviewed. Next, the same is done for work of the STAR RHIC collaboration (Silicon Vertex Tracker (SVT) project evolution and development in FY92, SVT software results from 1992, SVT instrumentation, FY93 SVT pion test beam). The instrumentation section deals with the design and installation of a target rapidity telescope for BNL experiment 814/877 and a repair scheme for the E814/E877 participant calorimeter. Finally, the theory part addresses bosonic kinetics: thermalization of mesons and the pion p perpendicular spectrum in ultrarelativistic heavy-ion collisions and non-equilibrium properties of hadronic mixtures
Modeling nuclear weak-interaction processes with relativistic energy density functionals
International Nuclear Information System (INIS)
Paar, N.; Marketin, T.; Vale, D.; Vretenar, D.
2015-01-01
Relativistic energy density functionals have become a standard framework for nuclear structure studies of ground state properties and collective excitations over the entire nuclide chart. In this paper, we review recent developments in modeling nuclear weak-interaction processes: Charge-exchange excitations and the role of isoscalar proton–neutron pairing, charged-current neutrino–nucleus reactions relevant for supernova evolution and neutrino detectors and calculation of β-decay rates for r-process nucleosynthesis. (author)
Relativistic quantum mechanics an introduction to relativistic quantum fields
Maiani, Luciano
2016-01-01
Written by two of the world's leading experts on particle physics and the standard model - including an award-winning former Director General of CERN - this textbook provides a completely up-to-date account of relativistic quantum mechanics and quantum field theory. It describes the formal and phenomenological aspects of the standard model of particle physics, and is suitable for advanced undergraduate and graduate students studying both theoretical and experimental physics.
Central depression of nuclear charge density distribution
International Nuclear Information System (INIS)
Chu Yanyun; Ren Zhongzhou; Wang Zaijun; Dong Tiekuang
2010-01-01
The center-depressed nuclear charge distributions are investigated with the parametrized distribution and the relativistic mean-field theory, and their corresponding charge form factors are worked out with the phase shift analysis method. The central depression of nuclear charge distribution of 46 Ar and 44 S is supported by the relativistic mean-field calculation. According to the calculation, the valence protons in 46 Ar and 44 S prefer to occupy the 1d 3/2 state rather than the 2s 1/2 state, which is different from that in the less neutron-rich argon and sulfur isotopes. As a result, the central proton densities of 46 Ar and 44 S are highly depressed, and so are their central charge densities. The charge form factors of some argon and sulfur isotopes are presented, and the minima of the charge form factors shift upward and inward when the central nuclear charge distributions are more depressed. Besides, the effect of the central depression on the charge form factors is studied with a parametrized distribution, when the root-mean-square charge radii remain constant.
Revisiting the even-odd staggering in fission-fragment yields
International Nuclear Information System (INIS)
Caamano, M.; Rejmund, F.; Schmidt, K. H.
2010-01-01
The even-odd staggering observed in the experimental fission-fragment nuclear-charge yields is investigated over a wide systematics of fission fragments measured at Lohengrin in direct kinematics and at GSI in inverse kinematics. The general increase of the even-odd staggering in the fission-fragment charge yields towards asymmetric charge splits is explained by the absorption of the unpaired nucleons by the heavy fragment. As a consequence, the well established trend of even-odd staggering in the fission fragment charge yields to decrease with the fissility is attributed in part to the asymmetry evolution of the charge distribution. This interpretation is strongly supported by the data measured at GSI, which cover the complete charge distribution and include precise yields at symmetry. They reveal that the even-odd effect around symmetry remains constant over a large range of fissility. (authors)
Slowly rotating general relativistic superfluid neutron stars with relativistic entrainment
International Nuclear Information System (INIS)
Comer, G.L.
2004-01-01
Neutron stars that are cold enough should have two or more superfluids or supercondutors in their inner crusts and cores. The implication of superfluidity or superconductivity for equilibrium and dynamical neutron star states is that each individual particle species that forms a condensate must have its own, independent number density current and equation of motion that determines that current. An important consequence of the quasiparticle nature of each condensate is the so-called entrainment effect; i.e., the momentum of a condensate is a linear combination of its own current and those of the other condensates. We present here the first fully relativistic modeling of slowly rotating superfluid neutron stars with entrainment that is accurate to the second-order in the rotation rates. The stars consist of superfluid neutrons, superconducting protons, and a highly degenerate, relativistic gas of electrons. We use a relativistic σ-ω mean field model for the equation of state of the matter and the entrainment. We determine the effect of a relative rotation between the neutrons and protons on a star's total mass, shape, and Kepler, mass-shedding limit
The Los Alamos suite of relativistic atomic physics codes
International Nuclear Information System (INIS)
Fontes, C J; Zhang, H L; Jr, J Abdallah; Clark, R E H; Kilcrease, D P; Colgan, J; Cunningham, R T; Hakel, P; Magee, N H; Sherrill, M E
2015-01-01
The Los Alamos suite of relativistic atomic physics codes is a robust, mature platform that has been used to model highly charged ions in a variety of ways. The suite includes capabilities for calculating data related to fundamental atomic structure, as well as the processes of photoexcitation, electron-impact excitation and ionization, photoionization and autoionization within a consistent framework. These data can be of a basic nature, such as cross sections and collision strengths, which are useful in making predictions that can be compared with experiments to test fundamental theories of highly charged ions, such as quantum electrodynamics. The suite can also be used to generate detailed models of energy levels and rate coefficients, and to apply them in the collisional-radiative modeling of plasmas over a wide range of conditions. Such modeling is useful, for example, in the interpretation of spectra generated by a variety of plasmas. In this work, we provide a brief overview of the capabilities within the Los Alamos relativistic suite along with some examples of its application to the modeling of highly charged ions. (paper)
Beyond ideal magnetohydrodynamics: resistive, reactive and relativistic plasmas
International Nuclear Information System (INIS)
Andersson, N; Dionysopoulou, K; Hawke, I; Comer, G L
2017-01-01
We develop a new framework for the modelling of charged fluid dynamics in general relativity. The model, which builds on a recently developed variational multi-fluid framework for dissipative fluids, accounts for relevant effects like the inertia of both charge currents and heat and, for mature systems, the decoupling of superfluid components. We discuss how the model compares to standard relativistic magnetohydronamics and consider the connection between the fluid dynamics, the microphysics and the underlying equation of state. As illustrations of the formalism, we consider three distinct two-fluid models describing (i) an Ohm’s law for resistive charged flows, (ii) a relativistic heat equation, and (iii) an equation representing the momentum of a decoupled superfluid component. As a more complex example, we also formulate a three-fluid model which demonstrates the thermo-electric effect. The new framework allows us to model neutron stars (and related systems) at a hierarchy of increasingly complex levels, and should enable us to make progress on a range of exciting problems in astrophysics and cosmology. (paper)
Fission fragment angular momentum
International Nuclear Information System (INIS)
Frenne, D. De
1991-01-01
Most of the energy released in fission is converted into translational kinetic energy of the fragments. The remaining excitation energy will be distributed among neutrons and gammas. An important parameter characterizing the scission configuration is the primary angular momentum of the nascent fragments. Neutron emission is not expected to decrease the spin of the fragments by more than one unit of angular momentum and is as such of less importance in the determination of the initial fragment spins. Gamma emission is a suitable tool in studying initial fragment spins because the emission time, number, energy, and multipolarity of the gammas strongly depend on the value of the primary angular momentum. The main conclusions of experiments on gamma emission were that the initial angular momentum of the fragments is large compared to the ground state spin and oriented perpendicular to the fission axis. Most of the recent information concerning initial fragment spin distributions comes from the measurement of isomeric ratios for isomeric pairs produced in fission. Although in nearly every mass chain isomers are known, only a small number are suitable for initial fission fragment spin studies. Yield and half-life considerations strongly limit the number of candidates. This has the advantage that the behavior of a specific isomeric pair can be investigated for a number of fissioning systems at different excitation energies of the fragments and fissioning nuclei. Because most of the recent information on primary angular momenta comes from measurements of isomeric ratios, the global deexcitation process of the fragments and the calculation of the initial fragment spin distribution from measured isomeric ratios are discussed here. The most important results on primary angular momentum determinations are reviewed and some theoretical approaches are given. 45 refs., 7 figs., 2 tabs
Relativistic electron diffraction at the UCLA Pegasus photoinjector laboratory
Energy Technology Data Exchange (ETDEWEB)
Musumeci, P. [UCLA Department of Physics and Astronomy, 475 Portola Plaza, Los Angeles, CA 90095-1547 (United States)], E-mail: musumeci@physics.ucla.edu; Moody, J.T.; Scoby, C.M. [UCLA Department of Physics and Astronomy, 475 Portola Plaza, Los Angeles, CA 90095-1547 (United States)
2008-10-15
Electron diffraction holds the promise to yield real-time resolution of atomic motion in an easily accessible environment like a university laboratory at a fraction of the cost of fourth-generation X-ray sources. Currently the limit in time-resolution for conventional electron diffraction is set by how short an electron pulse can be made. A very promising solution to maintain the highest possible beam intensity without excessive pulse broadening from space charge effects is to increase the electron energy to the MeV level where relativistic effects significantly reduce the space charge forces. Rf photoinjectors can in principle deliver up to 10{sup 7}-10{sup 8} electrons packed in bunches of {approx}100-fs length, allowing an unprecedented time resolution and enabling the study of irreversible phenomena by single-shot diffraction patterns. The use of rf photoinjectors as sources for ultrafast electron diffraction has been recently at the center of various theoretical and experimental studies. The UCLA Pegasus laboratory, commissioned in early 2007 as an advanced photoinjector facility, is the only operating system in the country, which has recently demonstrated electron diffraction using a relativistic beam from an rf photoinjector. Due to the use of a state-of-the-art ultrashort photoinjector driver laser system, the beam has been measured to be sub-100-fs long, at least a factor of 5 better than what measured in previous relativistic electron diffraction setups. Moreover, diffraction patterns from various metal targets (titanium and aluminum) have been obtained using the Pegasus beam. One of the main laboratory goals in the near future is to fully develop the rf photoinjector-based ultrafast electron diffraction technique with particular attention to the optimization of the working point of the photoinjector in a low-charge ultrashort pulse regime, and to the development of suitable beam diagnostics.
Relativistic electron diffraction at the UCLA Pegasus photoinjector laboratory
International Nuclear Information System (INIS)
Musumeci, P.; Moody, J.T.; Scoby, C.M.
2008-01-01
Electron diffraction holds the promise to yield real-time resolution of atomic motion in an easily accessible environment like a university laboratory at a fraction of the cost of fourth-generation X-ray sources. Currently the limit in time-resolution for conventional electron diffraction is set by how short an electron pulse can be made. A very promising solution to maintain the highest possible beam intensity without excessive pulse broadening from space charge effects is to increase the electron energy to the MeV level where relativistic effects significantly reduce the space charge forces. Rf photoinjectors can in principle deliver up to 10 7 -10 8 electrons packed in bunches of ∼100-fs length, allowing an unprecedented time resolution and enabling the study of irreversible phenomena by single-shot diffraction patterns. The use of rf photoinjectors as sources for ultrafast electron diffraction has been recently at the center of various theoretical and experimental studies. The UCLA Pegasus laboratory, commissioned in early 2007 as an advanced photoinjector facility, is the only operating system in the country, which has recently demonstrated electron diffraction using a relativistic beam from an rf photoinjector. Due to the use of a state-of-the-art ultrashort photoinjector driver laser system, the beam has been measured to be sub-100-fs long, at least a factor of 5 better than what measured in previous relativistic electron diffraction setups. Moreover, diffraction patterns from various metal targets (titanium and aluminum) have been obtained using the Pegasus beam. One of the main laboratory goals in the near future is to fully develop the rf photoinjector-based ultrafast electron diffraction technique with particular attention to the optimization of the working point of the photoinjector in a low-charge ultrashort pulse regime, and to the development of suitable beam diagnostics
Relativistic electron diffraction at the UCLA Pegasus photoinjector laboratory.
Musumeci, P; Moody, J T; Scoby, C M
2008-10-01
Electron diffraction holds the promise to yield real-time resolution of atomic motion in an easily accessible environment like a university laboratory at a fraction of the cost of fourth-generation X-ray sources. Currently the limit in time-resolution for conventional electron diffraction is set by how short an electron pulse can be made. A very promising solution to maintain the highest possible beam intensity without excessive pulse broadening from space charge effects is to increase the electron energy to the MeV level where relativistic effects significantly reduce the space charge forces. Rf photoinjectors can in principle deliver up to 10(7)-10(8) electrons packed in bunches of approximately 100-fs length, allowing an unprecedented time resolution and enabling the study of irreversible phenomena by single-shot diffraction patterns. The use of rf photoinjectors as sources for ultrafast electron diffraction has been recently at the center of various theoretical and experimental studies. The UCLA Pegasus laboratory, commissioned in early 2007 as an advanced photoinjector facility, is the only operating system in the country, which has recently demonstrated electron diffraction using a relativistic beam from an rf photoinjector. Due to the use of a state-of-the-art ultrashort photoinjector driver laser system, the beam has been measured to be sub-100-fs long, at least a factor of 5 better than what measured in previous relativistic electron diffraction setups. Moreover, diffraction patterns from various metal targets (titanium and aluminum) have been obtained using the Pegasus beam. One of the main laboratory goals in the near future is to fully develop the rf photoinjector-based ultrafast electron diffraction technique with particular attention to the optimization of the working point of the photoinjector in a low-charge ultrashort pulse regime, and to the development of suitable beam diagnostics.
Fully relativistic free-electron laser in a completely filled waveguide
International Nuclear Information System (INIS)
Farokhi, B.; Abdykian, A.
2005-01-01
An analysis of the azimuthally symmetrical, high frequency eigenmodes of a cylindrical metallic waveguide completely filled with a relativistic magnetized plasma is presented. A relativistic nonlinear wave equation is derived in a form which includes the coupling of EH and HE modes due to the finite axial magnetic field. Relativistic equations that permit calculation of the dispersion curves for four families of electromagnetic and electrostatic modes are derived. Numerical analysis is conducted to study the relativistic dispersion curves of various modes as a function of axial magnetic field B 0 . This treatment is shown that the dispersion curves dependent to γ in low frequency which is ignored in previous work. It is found that in drawn figures shown difference between relativistic and non-relativistic cases. The former each figure is treated for two orbit groups. This study is benefiting to facilities the development of devices for generation of high-power electromagnetic radiation, charged particle acceleration, and other applications of plasma waveguide. (author)
Fragmentation in 28Si-emulsion interactions at 3.7A GeV
International Nuclear Information System (INIS)
Singh, B.K.; Tuli, S.K.
1999-01-01
The results on fragmentation of a 3.7A GeV 28 Si projectile in interactions with different target nuclei in nuclear emulsion are presented. Limiting fragmentation behaviour of the projectile fragments is achieved at this energy. It is shown that the factorization principle for fragmentation cross-sections holds for light fragments only. A bond percolation prescription is able to reproduce the experimental observations for fragments with charge 4≤Z≤10. A rise in the production of helium fragments is also predicted by bond percolation
Solitary waves in dusty plasmas with weak relativistic effects in electrons and ions
Energy Technology Data Exchange (ETDEWEB)
Kalita, B. C., E-mail: bckalita123@gmail.com [Gauhati University, Department of Mathematics (India); Choudhury, M., E-mail: choudhurymamani@gmail.com [Handique Girls’ College, Department of Mathematics (India)
2016-10-15
Two distinct classes of dust ion acoustic (DIA) solitary waves based on relativistic ions and electrons, dust charge Z{sub d} and ion-to-dust mass ratio Q’ = m{sub i}/m{sub d} are established in this model of multicomponent plasmas. At the increase of mass ratio Q’ due to increase of relativistic ion mass and accumulation of more negative dust charges into the plasma causing decrease of dust mass, relativistic DIA solitons of negative potentials are abundantly observed. Of course, relativistic compressive DIA solitons are also found to exist simultaneously. Further, the decrease of temperature inherent in the speed of light c causes the nonlinear term to be more active that increases the amplitude of the rarefactive solitons and dampens the growth of compressive solitons for relatively low and high mass ratio Q’, respectively. The impact of higher initial streaming of the massive ions is observed to identify the point of maximum dust density N{sub d} to yield rarefactive relativistic solitons of maximum amplitude.
Relativistic quantum mechanics of bosons
International Nuclear Information System (INIS)
Ghose, P.; Home, D.; Sinha Roy, M.N.
1993-01-01
We show that it is possible to use the Klein-Gordon, Proca and Maxwell formulations to construct multi-component relativistic configuration space wavefunctions of spin-0 and spin-1 bosons in an external field. These wavefunctions satisfy the first-order Kemmer-Duffin equation. The crucial ingredient is the use of the future-causal normal n μ (n μ n μ =1, n 0 >0) to the space-like hypersurfaces foliating space-time, inherent in the concept of a relativistic wavefunction, to construct a conserved future-causal probability current four-vector from the second-rank energy-momentum tensor, following Holland's prescription. The existence of a Hermitian position operator, localized solutions, compatibility with the second quantized theories and the question of interpretation are discussed. (orig.)
Kinetic approach to relativistic dissipation
Gabbana, A.; Mendoza, M.; Succi, S.; Tripiccione, R.
2017-08-01
Despite a long record of intense effort, the basic mechanisms by which dissipation emerges from the microscopic dynamics of a relativistic fluid still elude complete understanding. In particular, several details must still be finalized in the pathway from kinetic theory to hydrodynamics mainly in the derivation of the values of the transport coefficients. In this paper, we approach the problem by matching data from lattice-kinetic simulations with analytical predictions. Our numerical results provide neat evidence in favor of the Chapman-Enskog [The Mathematical Theory of Non-Uniform Gases, 3rd ed. (Cambridge University Press, Cambridge, U.K., 1970)] procedure as suggested by recent theoretical analyses along with qualitative hints at the basic reasons why the Chapman-Enskog expansion might be better suited than Grad's method [Commun. Pure Appl. Math. 2, 331 (1949), 10.1002/cpa.3160020403] to capture the emergence of dissipative effects in relativistic fluids.
The relativistic electron wave equation
International Nuclear Information System (INIS)
Dirac, P.A.M.
1977-08-01
The paper was presented at the European Conference on Particle Physics held in Budapest between the 4th and 9th July of 1977. A short review is given on the birth of the relativistic electron wave equation. After Schroedinger has shown the equivalence of his wave mechanics and the matrix mechanics of Heisenberg, a general transformation theory was developed by the author. This theory required a relativistic wave equation linear in delta/delta t. As the Klein--Gordon equation available at this time did not satisfy this condition the development of a new equation became necessary. The equation which was found gave the value of the electron spin and magnetic moment automatically. (D.P.)
Volatility smile as relativistic effect
Kakushadze, Zura
2017-06-01
We give an explicit formula for the probability distribution based on a relativistic extension of Brownian motion. The distribution (1) is properly normalized and (2) obeys the tower law (semigroup property), so we can construct martingales and self-financing hedging strategies and price claims (options). This model is a 1-constant-parameter extension of the Black-Scholes-Merton model. The new parameter is the analog of the speed of light in Special Relativity. However, in the financial context there is no ;speed limit; and the new parameter has the meaning of a characteristic diffusion speed at which relativistic effects become important and lead to a much softer asymptotic behavior, i.e., fat tails, giving rise to volatility smiles. We argue that a nonlocal stochastic description of such (Lévy) processes is inadequate and discuss a local description from physics. The presentation is intended to be pedagogical.
Double Relativistic Electron Accelerating Mirror
Directory of Open Access Journals (Sweden)
Saltanat Sadykova
2013-02-01
Full Text Available In the present paper, the possibility of generation of thin dense relativistic electron layers is shown using the analytical and numerical modeling of laser pulse interaction with ultra-thin layers. It was shown that the maximum electron energy can be gained by optimal tuning between the target width, intensity and laser pulse duration. The optimal parameters were obtained from a self-consistent system of Maxwell equations and the equation of motion of electron layer. For thin relativistic electron layers, the gaining of maximum electron energies requires a second additional overdense plasma layer, thus cutting the laser radiation off the plasma screen at the instant of gaining the maximum energy (DREAM-schema.