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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 principal new point is that ultra-high spin of the elementary particles makes Einstein's gravity so strong, that its influence to metric is shifted from Planck to the Compton scale! Compatibility of the Kerr-Newman (KN) gravity with quantum theory is achieved by implementation of the supersymmetric Higgs model without modification of the Einstein-Maxwell gravity. We consider the nonperturbative bag-like solution to supersymmetric generalized LG field model, which creates a flat and supersymmetric vacuum state inside the bag, forming the Compton zone for consistent work of quantum theory. The bag is deformable, and its shape is controlled by BPS bound, providing compatibility of the bag boundary with external gravitational and electromagnetic (EM) field. In particular, for the spinning KN gravity the bag takes the form of oblate disk with a circular string placed on the disk border. Excitations of the KN EM field create circular traveling waves. The super-bag solution is naturally upgraded to the Wess-Zumino supersymmetric QED model, indicating a bridge from the nonperturbative super-bag to perturbative formalism of the conventional QED.

This report reviews methods of pattern recognition and event reconstruction used in modern high energy physics experiments. After a brief introduction into general concepts of particle detectors and statistical evaluation, different approaches in global and local methods of track pattern recognition are reviewed with their typical strengths and shortcomings. The emphasis is then moved to methods which estimate the particle properties from the signals which pattern recognition has associated. Finally, the global reconstruction of the event is briefly addressed.

A review of recent experimental measurements of the lifetime and mixing parameters of neutral D and B hadrons is presented. In particular, focus is given to measurements of D mixing and the Lambda_B lifetime.

I report on some scenarios where the gravitino is the dark matter and the supersymmetry breaking mediated by a gauge sector.

These reports present the results of the 2013 Community Summer Study of the APS Division of Particles and Fields ("Snowmass 2013") on the future program of particle physics in the U.S. Chapter 8, on the Instrumentation Frontier, discusses the instrumentation needs of future experiments in the Energy, Intensity, and Cosmic Frontiers, promising new technologies for particle physics research, and issues of gathering resources for long-term research in this area.

These reports present the results of the 2013 Community Summer Study of the APS Division of Particles and Fields ("Snowmass 2013") on the future program of particle physics in the U.S. Chapter 8, on the Instrumentation Frontier, discusses the instrumentation needs of future experiments in the Energy, Intensity, and Cosmic Frontiers, promising new technologies for particle physics research, and issues of gathering resources for long-term research in this area.

In this paper we describe ideas about the string landscape, and how to relate it to the physics of the Standard Model of particle physics. First, we give a short status report about heterotic string compactifications. Then we focus on the statistics of D-brane models, on the problem of moduli stabilization, and finally on some attempts to derive a probability wave function in moduli space, which goes beyond the purely statistical count of string vacua.

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.

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.

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.

Includes bibliographies and indexes

Includes bibliographies and indexes

The answer to the question in the title is: in search of new physics beyond the Standard Model, for which there are many motivations, including the likely instability of the electroweak vacuum, dark matter, the origin of matter, the masses of neutrinos, the naturalness of the hierarchy of mass scales, cosmological inflation and the search for quantum gravity. So far, however, there are no clear indications about the theoretical solutions to these problems, nor the experimental strategies to resolve them. It makes sense now to prepare various projects for possible future accelerators, so as to be ready for decisions when the physics outlook becomes clearer. Paraphrasing George Harrison, "If you don't yet know where you're going, any road may take you there."

A discussion is given on possible realization of the Single State Dominance (SSD) hypothesis in the case of the two-neutrino double beta decay(2nbb-decay) of 150Nd with 1^- ground state of the intermediate nucleus. We conclude that the SSD hypothesis is expected to be ruled out by precision measurement of differential characteristics of this process in running NEMO 3 or planed SuperNEMO experiments unlike some unknown low-lying 1^+ state of 150Pm does exist. This problem can be solved via (d,2He) charge-exchange experiment on 150Sm. Further, we address the question about possible violation of the Pauli exclusion principle for neutrinos and its consequences for the energy distributions of the 2nbb-decay of 150Nd. This phenomenon might be a subject of interest of NEMO 3 and SuperNEMO experiments as well.

Particle Physics best and some rare books from beginner to advanced.

Particle Physics best and some rare books from beginner to advanced.

$\mu-e$ conversion is the experimentally most interesting lepton flavor violating process. From a theoretical point of view it is an interesting interplay of particle and nuclear physics. The effective transition operator, depending on the gauge model, is in general described in terms of a combination of four terms of transition operators (isoscalar and isovector, Fermi-like as well as axial vector-like). The experimentally most interesting ground state to ground state transition is adequately described in terms of the usual proton and neutron form factors. These were computed in both the shell model and RPA. Since it is of interest to know the portion of the strength exhausted by the coherent (ground state to ground state) transition, the total transition rate to all final states must also be computed. This was done i) in RPA by explicitly summing over all final states ii) in the context of the closure approximation (using shell model and RPA for constructing the initial state) and iii) in the context of nuclear matter mapped into nuclei via a local density approximation. We found that, apart from small local oscillations, the conversion rate keeps increasing from light to heavy nuclear elements. We also find that the coherent mode is dominant (it exhausts more than 90\% of the sum rule). Various gauge models are discussed. In general the predicted branching ratio is much smaller compared to the present experimental limit.

$\mu-e$ conversion is the experimentally most interesting lepton flavor violating process. From a theoretical point of view it is an interesting interplay of particle and nuclear physics. The effective transition operator, depending on the gauge model, is in general described in terms of a combination of four terms of transition operators (isoscalar and isovector, Fermi-like as well as axial vector-like). The experimentally most interesting ground state to ground state transition is adequately described in terms of the usual proton and neutron form factors. These were computed in both the shell model and RPA. Since it is of interest to know the portion of the strength exhausted by the coherent (ground state to ground state) transition, the total transition rate to all final states must also be computed. This was done i) in RPA by explicitly summing over all final states ii) in the context of the closure approximation (using shell model and RPA for constructing the initial state) and iii) in the context of nuclear matter mapped into nuclei via a local density approximation. We found that, apart from small local oscillations, the conversion rate keeps increasing from light to heavy nuclear elements. We also find that the coherent mode is dominant (it exhausts more than 90\% of the sum rule). Various gauge models are discussed. In general the predicted branching ratio is much smaller compared to the present experimental limit.

Many of the classic problems of particle physics appear in a very different light when viewed from the perspective of the multiverse. Most importantly the two great ``fine tuning'' problems that motivate the field are far less serious when one accounts for the required anthropic constraints which exist in a multiverse. However, the challenge then becomes to construct a realistic physical theory of the multiverse and test it. I describe some phenomenology of the quark and lepton masses that may provide a window to the theory that underlies the multiverse.

The work in this thesis uses the formalism of thermal field theory. The major problem considered by us is the gravitational interaction of charged leptons in a medium. Working in the context of the linearized theory of gravity, we have deduced general expressions for the matter-induced $O(\alpha)$ corrections to the gravitational mass in normal matter background which contains electrons but not the other charged leptons. Explicit formulas are then given for the corrections in terms of the macroscopic parameters of the medium for a few special cases of the background gases. In the last part of the thesis, we have considered high-temperature, massless QED at zero chemical potential. We have investigated the gauge independence of the one-loop electron dispersion relation, taking subleading temperature dependence into account.

The early Universe inflation is well known as a promising theory to explain the origin of large scale structure of the Universe, a causal theory for the origin of primordial density fluctuations which may explain the observed density inhomogeneities and cosmic microwave fluctuations in the very early Universe, and to solve the early universe pressing problems for the standard hot big bang theory. For a resonable inflation model, the potential during inflation must be very flat in, at least, the direction of the inflaton. To construct a resonable inflation model, or the inflaton potential, all the known related astrophysics observations should be included. For a general tree-level hybrid inflation potential, which is not discussed fully so far for the quartic term, the parameters in it are shown how to be constrained via the astrophysics data observed and to be obtained to the expected accuracy by the soon lauched MAP and PLANCK satellite missions, as well as the consistent cosmology requirements. We find the effective inflaton mass parameter is in the TeV range, and the quartic term's self-coupling constant tiny, needs fine-tunning.

We review the hypothesis of the conserved vector current (CVC) within the Standard Model. In addition to the classic tests, such as pion beta decay and neutrino scattering, we mention recent tests involving LEP data. As well as providing a clear indication that the isovector current is not conserved, rho-omega mixing offers a fascinating opportunity to study CP violation at B-factories and we outline these ideas. Finally we briefly touch on a new approach to mass generation in the Standard Model which, for example, leads to the up-down mass difference which breaks CVC.

Neutrino oscillations occur only if it is impossible to determine $\nu$ mass by using conservation laws on measurements of nucleon-lepton system absorbing $\nu$. No oscillations if $\nu$ detector is mass spectrometer. Beam is split into components with different masses entering different counters. For each event only one counter will click and determine $\nu$ mass. Condensed matter physics needed to describe the $\nu$ detector, show it is not a mass spectrometer and identify which properties of the incident $\nu$ are unobservable. Relativistic quantum field theory can only describe $\nu$ wave function entering detector but not large uncertain momentum transfers to detector nor associated energy-momentum asymmetry. Absorption of incident $\nu$'s with different momenta but same energy leaves no trace of initial $\nu$ momentum difference in finite-size $\nu$ detector with effectively infinite mass at rest in laboratory. Undetectable recoil-free momentum is transferred to the detector with negligible energy transfer. The Debye-Waller factor common in X-ray diffraction by crystals gives probability that absorbing $\nu$'s with different momenta produce same nucleon-charged-lepton final state. Oscillations in time described in textbooks as interference between $\nu$ states with different energies not observable in realistic experiments. Different energy $\nu$'s not coherent because energy can be determined by measurements on initial and final states. Experiments detecting $\nu$ produced by $\pi to \mu \nu$ decay observe no electrons even though $\nu$ mass eigenstates produce electrons. Electron amplitude canceled by interference between amplitudes from different $\nu$ mass eigenstates with same energy and different momenta entering massive detector.

I give a short review of the holographic approach to quantum gravity, with emphasis on its application to deriving the properties of elementary particles.

New acceleration technology is mandatory for the future elucidation of fundamental particles and their interactions. A promising approach is to exploit the properties of plasmas. Past research has focused on creating large-amplitude plasma waves by injecting an intense laser pulse or an electron bunch into the plasma. However, the maximum energy gain of electrons accelerated in a single plasma stage is limited by the energy of the driver. Proton bunches are the most promising drivers of wakefields to accelerate electrons to the TeV energy scale in a single stage. An experimental program at CERN -- the AWAKE experiment -- has been launched to study in detail the important physical processes and to demonstrate the power of proton-driven plasma wakefield acceleration. Here we review the physical principles and some experimental considerations for a future proton-driven plasma wakefield accelerator.

We review how some open issues on Astro Particle physics can be studied by space born experiments in a complementary way to what is being done at underground and accelerators facilities

Includes bibliographical references and index

Opening Lecture at the Second Rencontres du Vietnam, October 21-28, 1995.

Opening Lecture at the Second Rencontres du Vietnam, October 21-28, 1995.

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.

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.

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.

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.

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.

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

I briefly review the conceptual developments that led to the Standard Model and discuss some of its remarkable qualitative features. On the way, I draw attention to several puzzling aspects that are beyond the reach of our present understanding of the basic laws of physics.

These reports present the results of the 2013 Community Summer Study of the APS Division of Particles and Fields ("Snowmass 2013") on the future program of particle physics in the U.S. Chapter 7, on Underground Laboratory Capabilities, discusses the prospects and requirements for large underground experiments such as those for neutrino physics, proton decay, and dark matter.

These reports present the results of the 2013 Community Summer Study of the APS Division of Particles and Fields ("Snowmass 2013") on the future program of particle physics in the U.S. Chapter 7, on Underground Laboratory Capabilities, discusses the prospects and requirements for large underground experiments such as those for neutrino physics, proton decay, and dark matter.

The neutrino mass generation mechanism, the nature of dark matter and the origin of the baryon asymmetry of the Universe are three compelling questions that cannot be accounted for in the Standard Model of particle physics. In this thesis we focus on all these issues by providing a possible solution in terms of a minimal extension of the Standard Model, consisting in the addition of a set of sterile fermions to the field content of the theory. Sterile fermions are gauge singlet fields, that can interact via mixing with the active neutrinos. We focus on the Inverse Seesaw mechanism, which is characterised by a low (TeV or lower) new physics scale and that can be tested in current and future experimental facilities. We present the model building analysis that points towards the minimal realisations of the mechanism, and the phenomenological study in order to accommodate light neutrino masses and to impose all the relevant experimental constraints in the model, as well as the expected experimental signatures. We show the viability of the sterile neutrino hypothesis as dark matter component, together with the characteristic features of this scenario in the minimal Inverse Seesaw mechanism. The possibility of successfully accounting for the baryon asymmetry in a testable realisation of the leptogenesis mechanism is also addressed. On the other hand it is important to look for manifestations of sterile fermions in laboratory experiments. We address this point by making predictions for the expected rates of rare lepton number violating decays of vector bosons, that can be mediated by sterile fermions, as well as by studying the impact of sterile fermions on global fit of electroweak precision data.

The action for a $(3+1)$-dimensional particle in very special relativity is studied. It is proved that massless particles only travel in effective $(2+1)$-dimensional space-time. It is remarkable that this action can be written as an action for a relativistic particle in a background gauge field and it is shown that this field causes the dimensional reduction. A new symmetry for this system is found. Furthermore, a general action with restored Lorentz symmetry is proposed for this system. It is shown that this new action contains very special relativity and two-time physics.

Once weakly-interacting massive particles (WIMPs) are unambiguously detected in direct-detection experiments, the challenge will be to determine what one may infer from the data. Here, I examine the prospects for reconstructing the local speed distribution of WIMPs in addition to WIMP particle-physics properties (mass, cross sections) from next-generation cryogenic and liquid-noble direct-detection experiments. I find that the common method of fixing the form of the velocity distribution when estimating constraints on WIMP mass and cross sections means losing out on the information on the speed distribution contained in the data and may lead to biases in the inferred values of the particle-physics parameters. I show that using a more general, empirical form of the speed distribution can lead to good constraints on the speed distribution. Moreover, one can use Bayesian model-selection criteria to determine if a theoretically-inspired functional form for the speed distribution (such as a Maxwell-Boltzmann distribution) fits better than an empirical model. The shape of the degeneracy between WIMP mass and cross sections and their offset from the true values of those parameters depends on the hypothesis for the speed distribution, which has significant implications for consistency checks between direct-detection and collider data. In addition, I find that the uncertainties on theoretical parameters depends sensitively on the upper end of the energy range used for WIMP searches. Better constraints on the WIMP particle-physics parameters and speed distribution are obtained if the WIMP search is extended to higher energy (~ 1 MeV).

Progress in Particle and Nuclear Physics 1990: Volume 24 , Issue CONTENTS. Digitized from IA1652712-02 . Previous issue: sim_progress-in-particle-and-nuclear-physics_1987-1989_18-22_cumulative-contents . Next issue: sim_progress-in-particle-and-nuclear-physics_1990_24 .

Progress in Particle and Nuclear Physics 1990: Volume 24 , Issue CONTENTS. Digitized from IA1652712-02 . Previous issue: sim_progress-in-particle-and-nuclear-physics_1987-1989_18-22_cumulative-contents . Next issue: sim_progress-in-particle-and-nuclear-physics_1990_24 .

Nuclear double beta decay provides an extraordinarily broad potential to search for beyond Standard Model physics, probing already now the TeV scale, on which new physics should manifest itself. These possibilities are reviewed here. First, the results of present generation experiments are presented. The most sensitive one of them - the Heidelberg-Moscow experiment in the Gran Sasso - probes the electron mass now in the sub eV region and will reach a limit of $\sim$ 0.1 eV in a few years. Basing to a large extent on the theoretical work of the Heidelberg Double Beta Group in the last two years, results are obtained also for SUSY models (R-parity breaking, sneutrino mass), leptoquarks (leptoquark-Higgs coupling), compositeness, right-handed W boson mass, test of special relativity and equivalence principle in the neutrino sector and others. One of the enriched $^{76}$Ge detectors also yields the most stringent limits for cold dark matter (WIMPs) to date by using raw data. A new Heidelberg experimental proposal (GENIUS) is described which would allow to increase the sensitivity for Majorana neutrino masses from the present level of at best 0.1 eV down to 0.01 or even 0.001 eV. It would further, already in a first step using only 100 kg of natural Ge detectors, cover almost the full MSSM parameter space for prediction of neutralinos as cold dark matter.

Progress in Particle and Nuclear Physics 1980: Volume 4 , Issue Index. Digitized from IA1646622-03 . Previous issue: sim_progress-in-particle-and-nuclear-physics_1980_4_contents . Next issue: sim_progress-in-particle-and-nuclear-physics_1980_4_0 .

Progress in Particle and Nuclear Physics 1993: Volume 30 , Issue CONTENTS. Digitized from IA1652712-02 . Previous issue: sim_progress-in-particle-and-nuclear-physics_1990-1991_24-27_cumulative-contents . Next issue: sim_progress-in-particle-and-nuclear-physics_1993_30 .

Progress in Particle and Nuclear Physics 1993: Volume 31 , Issue CONTENTS. Digitized from IA1652712-02 . Previous issue: sim_progress-in-particle-and-nuclear-physics_1993_30 . Next issue: sim_progress-in-particle-and-nuclear-physics_1993_31 .

We review the interpretation of gauge invariance as a mathematical redundancy required in a relativistic description of forces mediated by massless spin-1 and spin-2 particles. In this context we also review the Weinberg-Witten theorem and its implications. This leads us to consider a class of models in which long-range interactions are mediated by Goldstone bosons of spontaneous Lorentz violation. Since the Lorentz symmetry is realized non-linearly in the Goldstones, these models could evade the Weinberg-Witten theorem and the need for gauge invariance. In the case of gravity, the broken symmetry would protect the theory from having non-zero cosmological constant, while the compositeness of the graviton could provide a solution to the perturbative non-renormalizability of gravity. We also consider the phenomenology of spontaneous Lorentz violation by a vector VEV and the experimental limits thereon. We find the general low-energy effective action of the Goldstones of this kind of symmetry breaking minimally coupled to gravity. We compare this to the ghost condensate that has been proposed as a model for gravity in a Higgs phase. We then summarize the cosmological constant problems and show that models in which a scalar field causes super-acceleration of the universe generally exhibit instabilities. We discuss how the equation of state evolves in a universe where the dark energy is caused by the ghost condensate. We comment on the anthropic argument for a small cosmological constant and how it is weakened if the inflaton self-coupling varies over the landscape of possible universes. Finally, we discuss the reverse sprinkler, a problem in elementary fluid mechanics that had eluded a definitive treatment for decades.