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Light front formalism for composite systems is presented. Derivation of equations for bound state and scattering problems are given. Methods of constructing of elastic form factors and scattering amplitudes of composite particles are reviewed. Elastic form factors in the impulse approximation are calculated. Scattering amplitudes for relativistic bound states are constructed. Some model cases for transition amplitudes are considered. Deep inelastic form factors (structure functions) are expressed through light front wave functions. It is shown that taking into account of transverse motion of partons leads to the violation of Bjorken scaling and structure functions become square of transverse momentum dependent. Possible explanation of the EMC-effect is given. Problem of light front relativization of wave functions of lightest nuclei is considered. Scaling properties of deuteron, ${}^3He$ and ${}^4He$ light front wave functions are checked in a rather wide energy range.

I present a concise review of where we stand in particle physics today. First, I will discuss the status of the Standard Model, its open problems and the expected answers from the LHC. Then I will briefly review the avenues for New Physics that can be revealed by the LHC.

In this article we will overview several aspects of the string landscape, namely intersecting D-brane models and their statistics, possible model independent LHC signatures of intersecting brane models, flux compactification, moduli stabilization in type II compactifications, domain wall solutions and brane inflation.

In this work we provide a possible geometrical interpretation of the spin of elementary particles. In particular, it is investigated how the wave equations of matter are altered by the addition of an antisymmetric contribution to the metric tensor. In this scenario the explicit form of the matter wave equations is investigated in a general curved space-time, and then the equations are particularized to the flat case. Unlike traditional approaches of NGT, in which the gravitational field is responsible for breaking the symmetry of the flat Minkowski metric, we find more natural to consider that, in general, the metric of the space-time could be nonsymmetric even in the flat case. The physical consequences of this assumption are explored in detail. Interestingly enough, it is found that the metric tensor splits into a bosonic and a fermionic; the antisymmetric part of the metric is very sensitive to the spin and turns out to be undetectable for spinless scalar particles. However, fermions couple to it in a non-trivial way (only when there are interactions). In addition, the Pauli coupling is derived automatically as a consequence of the nonsymmetric nature of the metric

The state of our understanding of cosmology is reviewed from an astrophysical cosmologist point of view with a particular emphasis given to recent observations and their impact. Discussion is then presented on the implications for particle physics.

This paper documents package for the particle level fast simulation. The package is designed to complete the AcerMC generator framework with the easy-to-use simulation and reconstruction algorithms. The package provides, starting from list of particles in the event, the list of reconstructed jets, isolated electrons, muons and photons and reconstructed missing transverse energy. The AcerDET represents a simplified version of the package called ATLFAST, used since several years within ATLAS Collaboration. In the AcerDET version some functionalities of the former one have been removed, only the most crucial detector effects are implemented and the parametrisations are largely simplified. Therefore it is not representing in details neither ATLAS nor CMS detectors. Nevertheless, we believe that the package can be well adequate for some feasibility studies of the high pT physics at LHC and in future, after some adjustments, of other detectors as well.

This paper documents package for the particle level fast simulation. The package is designed to complete the AcerMC generator framework with the easy-to-use simulation and reconstruction algorithms. The package provides, starting from list of particles in the event, the list of reconstructed jets, isolated electrons, muons and photons and reconstructed missing transverse energy. The AcerDET represents a simplified version of the package called ATLFAST, used since several years within ATLAS Collaboration. In the AcerDET version some functionalities of the former one have been removed, only the most crucial detector effects are implemented and the parametrisations are largely simplified. Therefore it is not representing in details neither ATLAS nor CMS detectors. Nevertheless, we believe that the package can be well adequate for some feasibility studies of the high pT physics at LHC and in future, after some adjustments, of other detectors as well.

The orbital period of the binary pulsar PSR 1913+16 has been observed to decrease at the rate of $2.40\times 10^{-12}$ s/s which agrees with the prediction of the quadropole formula for gravitational radiation to within one percent. The decrease in orbital period may also occur by radiation of other massless particles like scalars and pseudoscalar Nambu-Goldstone bosons. Assuming that this energy loss is less than one percent of the gravitational radiation, we can establish bounds on couplings of these particles to nucleons. For a scalar nucleon coupling of the form $g_s~\phi~\bar\psi~\psi$ we find that $g_s < 3\times 10^{-19}$. From the radiation loss of massless Goldstone bosons we establish the upper bound $\theta /f < 7.5\times 10^{-16}$ GeV$^{-1}$ on the QCD vacuum angle $\theta$ and the scale $f$ at which the baryon number symmetry can be broken spontaneously.

We give a brief overview of 20 open theoretical questions in supersymmetric particle physics. The 20 questions we have chosen range from the GeV scale to the Planck scale, and include issues pertaining to the Minimal Supersymmetric Standard Model and its extensions, SUSY-breaking, cosmology, grand unified theories, and string theory. Throughout, our goal is to address those topics in which supersymmetry plays a fundamental role, and which are areas of active research in the field. This survey is written at an introductory level and is aimed at people who are not necessarily experts in the field. (To appear as an Overview Chapter in the review volume "Perspectives on Supersymmetry", edited by G. Kane, to be published by World Scientific.)

We present an extension of quantum field theory to the case when the spacetime topology fluctuates (spacetime foam). In this extension the number of bosonic fields becomes a variable and the ground state is characterized by a finite particle number density. It is shown that when the number of fields remains a constant, the standard field theory is restored. However, in the complete theory the ground state has a nontrivial properties. In particular, it produces an increase in the level of quantum fluctuations in the field potentials and an additional renormalization of masses of particles. We examine fluctuations of massless fields and show that in the presence of a temperature (thermal state) these fluctuations has 1/f spectrum. Thus, the main prediction of the theory is that our universe should be filled with a random electromagnetic field which should produce an additional 1/f - noise in electric circuits.

We present an extension of quantum field theory to the case when the spacetime topology fluctuates (spacetime foam). In this extension the number of bosonic fields becomes a variable and the ground state is characterized by a finite particle number density. It is shown that when the number of fields remains a constant, the standard field theory is restored. However, in the complete theory the ground state has a nontrivial properties. In particular, it produces an increase in the level of quantum fluctuations in the field potentials and an additional renormalization of masses of particles. We examine fluctuations of massless fields and show that in the presence of a temperature (thermal state) these fluctuations has 1/f spectrum. Thus, the main prediction of the theory is that our universe should be filled with a random electromagnetic field which should produce an additional 1/f - noise in electric circuits.

Bohr's dictum "Physical phenomena are observed relative to different experimental setups" is applied to a set of binary elements that represent the smallest units of information. A description relative to "macroscopic" setups of such elements is formulated. This requires the introduction of a Hilbert space formalism. It is shown, that the Hilbert space is symmetric with respect to the de Sitter group SO(3,2). For macroscopic setups SO(3,2) is approximated by the Poincare group. A space-time manifold is obtained that expresses the orientation of macroscopic setups relative to each other. Individual binary elements can then be given a "position" relative to macroscopic reference frames. To an observer binary elements will then exhibit properties of massive particles. This informational approach to particle physics determines a mass scale, delivers interaction terms for all four interactions and is, in principle, capable of fixing coupling constants and masses. Despite its simplicity it forms a promising basis for a theoretical model that leads beyond the standard model.

Introduction Theory of electromagnetic excitation and dissociation (Inelastic scattering at high energies: one-photon exchange, semiclassical approach and Glauber theory; Higher order electromagnetic effects, small xi-approximation) Discussion of experimental results for nuclear structure Coulomb dissociation as a tool to measure radiative capture processes relevant to nuclear astrophysics Antihydrogen production and electromagnetic processes at relativistic heavy ion colliders Conclusions

This two-part article considers certain fundamental symmetries of nature, namely the discrete symmetries of parity (P), charge conjugation (C) and time reversal (T), and their possible violation. Recent experimental results are discussed in some depth. In the first part of this article we present a general background and discuss parity violation.

Heretofore unrecognized (i.e., "hidden") Lorentz-invariant vector observables in the fermion sector (i.e., flavor-defining fermion "coordinates") are shown to indirectly explain most, if not all, of the so-called "accidental" (internal) symmetries associated with fundamental fermions (quarks and leptons), by explaining quark and lepton flavors, flavor doublets and families. Moreover, these new fermion coordinates lead to quantitative constraints on neutrino mixtures that are found to be in good agreement with current experimental observations.

We study the influence of boundaries on chiral effects in hot dense relativistic spinor matter in a strong magnetic field which is orthogonal to the boundaries. The most general set of boundary conditions ensuring the confinement of matter within the boundaries is employed. We find that the chiral magnetic effect disappears, whereas the chiral separation effect stays on, becoming dependent on temperature and on a choice of boundary conditions. As temperature increases from zero to large values, a stepped-shape behaviour of the chiral separation effect as a function of chemical potential is changed to a smooth one. A choice of the boundary condition can facilitate either amplification or diminution of the chiral separation effect; in particular, the effect can persist even at zero chemical potential, if temperature is finite. This points at a significant role of boundaries for physical systems with hot dense magnetized spinor matter, i.e. compact astrophysical objects (neutron stars and magnetars), relativistic heavy-ion collisions, novel materials known as the Dirac and Weyl semimetals.

We review lattice results relevant for pion and kaon physics with the aim of making them easily accessible to the particle physics community. Specifically, we review the determination of the light-quark masses, the form factor f_+(0), relevant for the semileptonic K -> pi transition at zero momentum transfer as well as the ratio f_K/f_pi of decay constants and discuss the consequences for the elements V_{us} and V_{ud} of the CKM matrix. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2)_LxSU(2)_R and SU(3)_LxSU(3)_R Chiral Perturbation Theory and review the determination of the B_K parameter of neutral kaon mixing. We introduce quality criteria and use these when forming averages. Although subjective and imperfect, these criteria may help the reader to judge different aspects of current lattice computations. Our main results are summarized in section 1.2, but we stress the importance of the detailed discussion that underlies these results and constitutes the bulk of the present review.

Topological media are gapped or gapless fermionic systems, whose properties are protected by topology, and thus are robust to deformations of parameters of the system and generic. We discuss the class of gapless topological media, which contains the quantum vacuum of Standard Model in its symmetric phase, and condensed matter systems with zeroes in the energy spectrum, which form Fermi surfaces, Weyl and Dirac points, Dirac lines, Khodel-Shaginyan flat bands, etc. Some zeroes are topologically protected, being characterized by topological invariants, expressed in terms of Green's function. For stability of the others the ${\bf p}$-space topology must be accompanied by symmetry. Vacua with Weyl points serve as a source of effective relativistic quantum fields emerging at low energy: chiral fermions, effective gauge fields and tetrad gravity emerge together in the vicinity of a Weyl point. The accompanying effects, such as chiral anomaly, electroweak baryo-production and chiral vortical effect, are expressed via the symmetry protected ${\bf p}$-space invariants. The gapless topological media exhibit the bulk-surface and bulk-vortex correspondence: which in particular may lead to the flat band on the surface of the system or in the core of topological defects. The materials with flat band in bulk, on the surface or within the dislocations have singular density of states, which crucially influences the critical temperature of the superconducting transition in such media. While in all the known superconductors the transition temperature is exponentially suppressed as a function of the pairing interaction, in the flat band the transition temperature is proportional to the pairing interaction, and can be essentially higher. The ${\bf p}$-space topology may give us the general recipe for search or artificial fabrication of the room-temperature superconductors.

A personal perspective on the future challenges of research in particle physics is presented with emphasis on the role of DIS physics in this endeavour.

Extending the scalar sector helps in studying the Higgs mechanism and some Standard Model problems. We implement the correspondence between the gauge-dependent elementary states and the non-perturbative non-abelian gauge-invariant asymptotic states, necessary to study the non-perturbative phenomenology of two-Higgs-doublet models. The Flavour and CP violation in experimental data follows a hierarchical pattern, accounted by the Standard Model. We define the Minimal Flavour Violation condition with six spurions in effective field theories, implying Flavour and CP violation entirely dependent on the fermion mixing matrices but independent of the fermion masses hierarchy; it is renormalization-group invariant. We study the phenomenology of renormalizable two-Higgs-doublet models which verify the defined condition as consequence of a symmetry; new light physical scalars, mediating Flavour Changing Neutral Currents, are allowed by flavour data without flavour coefficients beyond the Standard Model; we tested the models with C++ libraries linked by the symbolic skills of the GiNaC library and we propose more libraries supporting a systematic search for Flavour Changing Neutral Currents. We also map the complex to the real Poincare group representations, derive the free Dirac equation requiring covariant localizability of the representations and study Localization and gauge symmetries in Quantum Field Theory.

We present the first results on 3-particle $\Delta\eta$-$\Delta\eta$ correlations in minimum bias $d$+Au, peripheral and central Au+Au collisions at $\sqrt{{\it s}_{NN}}$ = 200 GeV measured by the STAR experiment. The analysis technique is described in detail. The ridge particles, observed at large $\Delta\eta$ in dihadron correlations in central Au+Au collisions, appear to be uniformly distributed over the measured $\Delta\eta$-$\Delta\eta$ region in 3-particle correlation. The results, together with theoretical models, should help further our understanding of the underlying physics of the ridge.

The inclusion of running coupling effects in the BK-JIMWLK evolution equations considerably reduces the energy dependence of the saturation scale with respect to previous estimates based on fits to HERA data. We discuss how such slowdown affects the expectations for particle multiplicities in Pb-Pb collisions at LHC energies. Our prediction is based on the use of k_t-factorization and on the use of unintegrated gluon distributions taken from the numerical solutions of the BK equation with running coupling. We obtain a central value dN/d\eta(sqrt{s}=5.5 TeV)(\eta=0)~1390.

We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

#OTD 1964: Murray Gell-Mann, Yuval Ne'eman and Richard Feynman discussed particle physics on Horizon https://t.co/6T6I7dsmoQ Source: https://twitter.com/BBCArchive/status/757612959560458240 Uploader: BBC Archive

#OTD 1964: Murray Gell-Mann, Yuval Ne'eman and Richard Feynman discussed particle physics on Horizon https://t.co/6T6I7dsmoQ Source: https://twitter.com/BBCArchive/status/757612959560458240 Uploader: BBC Archive

#OTD 1964: Murray Gell-Mann, Yuval Ne'eman and Richard Feynman discussed particle physics on Horizon https://t.co/6T6I7dsmoQ Source: https://twitter.com/BBCArchive/status/757612959560458240 Uploader: BBC Archive

Includes bibliographies and indexes

Includes bibliographies and indexes

Includes bibliographies and indexes

This first open access volume of the handbook series contains articles on the standard model of particle physics, both from the theoretical and experimental perspective. It also covers related topics, such as heavy-ion physics, neutrino physics and searches for new physics beyond the standard model. A joint CERN-Springer initiative, the “Particle Physics Reference Library” provides revised and updated contributions based on previously published material in the well-known Landolt-Boernstein series on particle physics, accelerators and detectors (volumes 21A,B1,B2,C), which took stock of the field approximately one decade ago. Central to this new initiative is publication under full open access.

This first open access volume of the handbook series contains articles on the standard model of particle physics, both from the theoretical and experimental perspective. It also covers related topics, such as heavy-ion physics, neutrino physics and searches for new physics beyond the standard model. A joint CERN-Springer initiative, the “Particle Physics Reference Library” provides revised and updated contributions based on previously published material in the well-known Landolt-Boernstein series on particle physics, accelerators and detectors (volumes 21A,B1,B2,C), which took stock of the field approximately one decade ago. Central to this new initiative is publication under full open access.

This first open access volume of the handbook series contains articles on the standard model of particle physics, both from the theoretical and experimental perspective. It also covers related topics, such as heavy-ion physics, neutrino physics and searches for new physics beyond the standard model. A joint CERN-Springer initiative, the “Particle Physics Reference Library” provides revised and updated contributions based on previously published material in the well-known Landolt-Boernstein series on particle physics, accelerators and detectors (volumes 21A,B1,B2,C), which took stock of the field approximately one decade ago. Central to this new initiative is publication under full open access.

On some equations concerning the Ramanujan unpublished papers and four-dimensional pseudo-particle. New possible mathematical connections with various parameters of Theoretical Physics, String Theory, Supersymmetry Breaking and Number Theory

Progress in Particle and Nuclear Physics 1991: Volume 26 , Issue CONTENTS. Digitized from IA1646622-03 . Previous issue: sim_progress-in-particle-and-nuclear-physics_1988-1990_20-24_contents . Next issue: sim_progress-in-particle-and-nuclear-physics_1991_26_0 .

Progress in Particle and Nuclear Physics 1991: Volume 27 , Issue CONTENTS. Digitized from IA1646622-03 . Previous issue: sim_progress-in-particle-and-nuclear-physics_1991_26_0 . Next issue: sim_progress-in-particle-and-nuclear-physics_1991_27_0 .

Progress in Particle and Nuclear Physics 1992: Volume 29 , Issue CONTENTS. Digitized from IA1652712-02 . Previous issue: sim_progress-in-particle-and-nuclear-physics_1992_28 . Next issue: sim_progress-in-particle-and-nuclear-physics_1992_29 .

Progress in Particle and Nuclear Physics 1993: Volume 30 , Issue CONTENTS. Digitized from IA1646622-03 . Previous issue: sim_progress-in-particle-and-nuclear-physics_1990-1991_24-27_contents . Next issue: sim_progress-in-particle-and-nuclear-physics_1993_30_0 .

Nuclear Physics B Particle Physics 1986 - 1987: Volume B271-B280 , Issue CUMULATIVE INDEX. Digitized from IA1653434-07 . Previous issue: sim_nuclear-physics-b_1987-12-21_b294_4 .

Nuclear Physics B Particle Physics 1986 - 1987: Volume B271-B280 , Issue CUMULATIVE INDEX. Digitized from IA1653434-07 . Previous issue: sim_nuclear-physics-b_1987-12-21_b294_4 .

I discuss topics in Particle Physics applying the novel ontological formulation of Relativistic Quantum Field Theory due to David Bohm. I argument that particle physicists might too benefit from this truly novel way of thinking Physics.

Recently we’ve read that there is an excellent Cold Fusion experiment performed by Prof Arata, showing that the promise of CF/LENR (Low Energy Nuclear Reaction) is rekindled.