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Accounting for the effects of local parity nonconservation in a strongly interacting medium is implemented within the framework of the Monte Carlo model. Predictions are obtained for the distributions of the invariant masses of di-muons and di-electrons from the decays of light vector mesons in Pb–Pb collisions at the LHC energy, taking into account the resolution of the detecting systems. The influence of fluctuations of the axial chemical potential is estimated. [ABSTRACT FROM AUTHOR]

Hindering of inversion transitions and a violation of mirror symmetry of the right- and left-handed configurations of diazabizyclooctane (dabco, N2C6H12) enantiomers has been studied with lowtemperature adiabatic calorimetry. The dabco molecules were sandwiched in a high-porous layered structure of a metal organic framework (MOF) compound. We show from the data of low-temperature adiabatic calorimetry and ¹H NMR spin relaxation method that hindering of inversion transitions of dabco molecules cannot be associated with the influence of the intracrystalline self-consistent molecular field as a continuously monitoring environment within the quantum Zeno effect. In addition, lack of another manifestation of this effect associated with the collisional suppression of the inversion transitions in MOF samples impregnated by helium has been shown. These results lead to the conclusion that chiral polarization is related to the fundamental effect of parity nonconservation. [ABSTRACT FROM AUTHOR]

We employ triple-resonance vibrational overtone excitation to access quasibound states of water from several fully characterized bound states of the molecule. Comparison of the measured dissociation spectra allows a rigorous assignment of rotational quantum numbers J, nuclear spin and parity, and a tentative vibrational characterization of the observed resonances. Their asymmetrical shapes (Fano profiles) reflect interference of dipole moments for transitions to these resonances with that to the dissociative continuum. The assignments and Fano profile parameters of the resonances stand as a benchmark for the extension of accurate quantum-mechanical calculations to activated complexes of water. The narrow widths of some of these resonances indicate that water molecules may survive for as long as up to 60 ps in states above the dissociation threshold. We consider the possible implication of such long-lived states for the kinetics of water dissociation and the OH+H association reaction. [ABSTRACT FROM AUTHOR]

Parity violation (PV) effects for a series of chiral molecules of the type SeOXY (X,Y=H, F, Cl, Br, or I) are predicted from four-component relativistic Hartree–Fock and density functional theory. All optimized SeOXY structures are nonplanar with large inversion barriers ranging from 23 to 55 kcal/mol; thus, all SeOXY molecules remain enantiomeric stable on the laboratory time scale. The variation in PV between the different methods applied is small enough for each molecule to allow for an accurate prediction of these effects. At the respective equilibrium geometries the enantiomers exhibit parity violating energy shifts of up to 17 Hz. The Se–O stretching mode of all investigated SeOXY molecules lies in the experimentally favorable CO2 laser range of ∼1000 cm-1. We therefore investigated PV effects in vibrational transitions along a single normal mode using Dirac–Kohn–Sham theory. The PV energy differences in the fundamental Se–O stretching mode amount up to 110 mHz (largest for SeOClI) and are larger compared to the C–F stretching mode of CHFBrI previously investigated. Hence these SeOXY molecules are ideal candidates for the future experimental gas-phase detection of PV in vibrational spectra of chiral molecules. [ABSTRACT FROM AUTHOR]

The authors present the results of their calculation for the parity nonconserving 5p66s1/2→5p65d3/2 transition in Ba+ using the relativistic coupled-cluster theory in the singles, doubles, and partial triples approximation. The contributions from the leading intermediate states are explicitly considered. It is found that the largest contribution comes from the |5p66p1/2> state. Their results are in reasonable agreement with other calculations. [ABSTRACT FROM AUTHOR]

A systematic four-component relativistic study of the parity nonconservation (PNC) contribution to the (isotropic) NMR shielding constants of chiral molecules is presented for the P enantiomers of the series H2X2 (X=17O,33S,77Se,125Te,209Po). The PNC contributions are obtained within a linear response approach at the Hartree-Fock level. A careful design of the basis sets is necessary. The four-component relativistic results based on the Dirac-Coulomb Hamiltonian are compared with the nonrelativistic Lévy-Leblond results and those obtained by the spin-free modified Dirac Hamiltonian. The calculations confirm the nonrelativistic scaling law Z2.4 of the PNC contribution with respect to nuclear charge Z. However, the calculations also show that the overall scaling is significantly modified by relativistic effects. The scalar relativistic effect scales as Z4.7 for the selected set of molecules, whereas the spin-orbit effect, of opposite sign, scales better than Z6 and completely dominates the PNC contribution for the heaviest elements. This opens up the intriguing possibility of the experimental observation of PNC effects on NMR parameters of molecules containing heavy atoms. The presented formalism is expected to be valuable in assisting the search for suitable candidate molecules. [ABSTRACT FROM AUTHOR]

In this paper I will focus on the case of the discovery of parity nonconservation in weak interactions from the period spanning 1947–1957, and the lessons this episode provides for successful theory construction in HEP. I aim to (a) summarize the history into a coherent story for philosophers of science, and (b) use the history as a case study for the epistemological evolution of the understanding of weak interactions in HEP. Iconclude with some philosophical lessons regarding theory construction in physics. • Discovery of parity violation came despite the theoretical framework in 1950s physics. • Early theory construction thrived due to close contact between theory and experiment. • Modern fundamental physics should shift toward a focus on precision experiments. • Theoretical physics requires constant experimental checks in order to be confirmed. [ABSTRACT FROM AUTHOR]

We investigate the parity-violating pion–nucleon–nucleon coupling constant h π N N 1 , based on the chiral quark-soliton model. We employ an effective weak Hamiltonian that takes into account the next-to-leading order corrections from QCD to the weak interactions at the quark level. Using the gradient expansion, we derive the leading-order effective weak chiral Lagrangian with the low-energy constants determined. The effective weak chiral Lagrangian is incorporated in the chiral quark-soliton model to calculate the parity-violating πNN constant h π N N 1 . We obtain a value of about 10 − 7 at the leading order. The corrections from the next-to-leading order reduce the leading order result by about 20%. [ABSTRACT FROM AUTHOR]

This article introduced Prof. WU Jian-xiong's most prominent scientific achievements and her life story. No matter in middle school or university, the young Jian-xiong always is a most understanding student, she selected the nuclear physics as her major, and went on the road of experimental physics, and made the excellent contribution to the βdecay experiment research. The paper focuses on the parity nonconservation experiment with epoch-making significance made by Prof WU. At the end of this paper, Prof. WU herself reminiscence is expounded, and the praise and miss to her are narrated. [ABSTRACT FROM AUTHOR]

The observation in the title made earlier in association with the Pais-Uhlenbeck oscillator with equal frequencies is illustrated for an elementary matrix model. In the limit $N \to \infty $ ( N being the order of the exceptional point), an infinity of nontrivial states that do not change their norm during evolution appear. These states have real energies lying in a continuous interval. The norm of the 'precursors' of these states at large finite N is not conserved, but the characteristic time scale where this nonconservation shows up grows linearly with N. [ABSTRACT FROM AUTHOR]

Copyright of Technical Journal / Tehnički Glasnik is the property of Polytechnic of Varazdin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work builds on the Volterra series formalism presented in Dreisigmeyer and Young (J Phys A 36: 8297, ) to model nonconservative systems. Here we treat Lagrangians and actions as 'time dependent' Volterra series. We present a new family of kernels to be used in these Volterra series that allow us to derive a single retarded equation of motion using a variational principle. [ABSTRACT FROM AUTHOR]

New discoveries and theories are crucial for the development of science, but they are often initially resisted by the scientific community. This paper analyses resistance to scientific discoveries that supplement previous research results or conclusions with new phenomena, such as long chains in macromolecules, Alfvén waves, parity nonconservation in weak interactions and quasicrystals. Construal-level theory is used to explain that the probability of new discoveries may be underestimated because of psychological distance. Thus, the insufficiently examined scope of an accepted theory may lead to overstating the suitable scope and underestimating the probability of its undiscovered counter-examples. Therefore, psychological activity can result in people instinctively resisting new discoveries. Direct evidence can help people judge the validity of a hypothesis with rational thinking. The effects of authorities and textbooks on the resistance to discoveries are also discussed. From the results of our analysis, suggestions are provided to reduce resistance to real discoveries, which will benefit the development of science. [ABSTRACT FROM AUTHOR]

Recent results concerning negative-parity states in 16C are analyzed in terms of the shell model and a simple weak-coupling model. We suggest the state at 6.28 MeV is 2-, and the state near 6.1 MeV is not 3-, but probably 1- (0-). [ABSTRACT FROM AUTHOR]

In the framework of Friedmann-Lemaitre-Robertson-Walker cosmology modified by entropic issues, the sign change of the inhomogeneous term associated with the nonconservation energy equation for cosmic fluid is discussed; specifically, this is a bare/effective study of the equation of state for this fluid through a bare ( ω)/effective ( ω) description. In the bare case, where there is a nonconserved equation of state, the change in the sign of the inhomogeneous term at different times of the cosmic evolution is described. By redefining the adiabatic ω-parameter, the usual scheme for cosmic evolution can be recovered. In the effective case, if evolution is driven by dust or the cosmological constant, the universe evolves towards thermal equilibrium. However, by incorporating a quantum correction, only the cosmological constant can lead to thermal equilibrium. This correction avoids the future singularity that is present when it is not incorporated. [ABSTRACT FROM AUTHOR]

Abstract: The critical forces of massless conservative systems can be calculated using equilibrium conditions on the deformed systems. However, if non-trivial equilibrium conditions are absent (e.g., Beck's and Ziegler's column), then the equilibrium method is not applicable. Therefore, these systems were supplied with mass and calculations were performed dynamically. This manuscript demonstrates that the static stability of massless non-conservative systems can be calculated using the energetic stability criterion. [Copyright &y& Elsevier]

Abstract: The history and phenomenology of hadronic parity nonconservation (PNC) is reviewed. We discuss the current status of the experimental tests and theory. We describe a reanalysis of the asymmetry for that, when combined with other experimental constraints and with a recent lattice QCD calculation of the weak pion–nucleon coupling , reveals a much more consistent pattern of PNC couplings. In particular, isoscalar coupling strengths are similar to but somewhat larger than the “best value” estimate of Donoghue, Desplanques, and Holstein, while both lattice QCD and experiment indicate a suppressed . We discuss the relationship between meson-exchange models of hadronic PNC and formulations based on effective theory, stressing their general compatibility as well as the challenge presented to theory by experiment, as several of the most precise measurements involve significant momentum scales. Future directions are proposed. [Copyright &y& Elsevier]

Three pion-dominated observables of the parity-nonconserving interactions between the cold neutrons and parahydrogen are calculated. The transversely polarized neutron spin rotation, unpolarized neutron longitudinal polarization, and photon asymmetry of the radiative polarized neutron capture are considered. For the numerical evaluation of the observables, the strong interactions are taken into account by the Reid93 potential and the parity-nonconserving interactions by the DDH and EFT models including two different EFT parity-nonconserving two-pion exchange potentials. [ABSTRACT FROM AUTHOR]

We apply the sum-over-states approach to calculate partial contributions to parity nonconservation (PNC) in cesium [Porsev, Beloy, and Drevianko, Phys. Rev. Lett. 102,181601 (2009)]. We find significant corrections to two nondominating terms coming from the contribution of the core and highly excited states (n > 9, the so called tail). When these differences are taken into account the result of Porsev et at., EPNC = 0.8906(24) × 10-11i(-Qw/N) changes to 0.8977 (40), coming into good agreement with our previous calculations, 0.8980 (45). The interpretation of the PNC measurements in cesium still indicates reasonable agreement with the standard model (1.5σ); however, it gives new constraints on physics beyond it. [ABSTRACT FROM AUTHOR]

We review the current status of the study of parity and time invariance violation in atoms, nuclei and molecules. We focus on parity nonconservation (PNC) in cesium (CS) and three of the most promising areas of research: (i) PNC in a chain of isotopes, (ii) search for nuclear anapole moments, and (iii) search for permanent electric dipole moments (EDMs) of atoms and molecules, which in turn are caused by either an electron EDM or nuclear T, P-odd moments such as a nuclear EDM or nuclear Schiff moment. [ABSTRACT FROM AUTHOR]

This paper presents the dynamic stability analysis of a spinning, thick, annular disk loaded by a circumferentially distributed frictional traction. Considering the automotive/aircraft disc brake as a representative system for this study, the brake rotor is modeled as a spinning annular disk in the context of the Mindlin's thick plate theory to ensure a more accurate estimation of the eigenvalues when the disk involves high circumferential vibration modes that are often observed in unstable disc brake rotors. The frictional traction is decomposed into in-plane and transverse components. The in-plane component is equilibrated by membrane stresses while the transverse component is a nonconservative follower-type force that is the source of the dynamic instability of the disk. The corresponding nonconservative eigenvalue problem is formulated based on the modal expansion theory for traveling waves and direct discretization technique. The brake pad or stator is modeled as a second order viscoelastic subgrade that reacts to both transverse and shearing motion of the disc brake rotor. The instability behavior of the disk is investigated by examining the resulting complex eigenvalues under various combinations of the system para-meters such as frictional traction, geometry of the disk, and viscoelastic properties of the pad lining. In order to assess the effects of shear deformations and rotary inertia of the disk model under such loading conditions, results are compared with those from the classical Kirch-hoff--Love's thin disk model. Based on the phase angle information of the eigenvalues, it is found that there exists a critical value of friction, slenderness ratio of the disk, and the size of pad lining at which the transverse amplitude growth rates of high circumferential vibration modes drastically increase. Unless damping is present in the disc brake rotor or pad lining, vibration modes with repeated eigenvalues are found to be always unstable either by means of divergence or flutter even for a very small nonconservative traction load. [ABSTRACT FROM AUTHOR]

CP symmetry is defined and examined. The failure of CP symmetry in the kaon, D and B systems is outlined and discussed. The discussion is extended to leptons. [ABSTRACT FROM AUTHOR]

We study the design of network codes for M-source N-relay (M - N - \1) wireless networks over slow-fading channels. Binary frame-wise network coding (BFNC) based on cyclic-shifting matrices is developed to achieve full diversity and good coding gain. We develop a criterion in the context of BFNC that if satisfied guarantees to achieve full diversity gain. Based on this criterion, we propose an algorithm to design low-complexity encoders for a BFNC scheme by exploiting quasi-cyclic low-density parity-check (LDPC) code structures. We also design practical decoders based on the belief propagation decoding principle with a focus on large block lengths. Numerical results demonstrate that our BFNC schemes have substantial benefits over previous complex field and Galois field network coding schemes in the sense that our BFNC schemes can achieve full diversity gain and high coding gain for arbitrary block lengths with low encoding/decoding complexity. [ABSTRACT FROM PUBLISHER]

Nonlinear piezoelectric effects in flexural energy harvesters have recently been demonstrated for drive amplitudes well within the scope of anticipated vibration environments for power generation. In addition to strong softening effects, steady-state oscillations are highly damped as well. Nonlinear fluid damping was previously employed to successfully model drive dependent decreases in frequency response due to the high-velocity oscillations, but this article instead harmonizes with a body of literature concerning weakly excited piezoelectric actuators by modeling nonlinear damping with nonconservative piezoelectric constitutive relations. Thus, material damping is presumed dominant over losses due to fluid-structure interactions. Cantilevers consisted of lead zirconate titanate (PZT)-5A and PZT-5H are studied, and the addition of successively larger proof masses is shown to precipitate nonlinear resonances at much lower base excitation thresholds while increasing the influence of higher-order nonlinearities. Parameter identification results using a multiple scales perturbation solution suggest that empirical trends are primarily due to higher-order elastic and dissipation nonlinearities and that modeling linear electromechanical coupling is sufficient. This article concludes with the guidelines for which utilization of a nonlinear model is preferred. [ABSTRACT FROM PUBLISHER]

Abstract: Theoretical concepts for the production, preservation and control of polarized highly charged ion beams in storage rings are investigated. It is argued that hydrogen-like ions can be polarized efficiently by optical pumping of the Zeeman sublevels of ground state hyperfine levels and that the maximum achievable nuclear polarization exceeds 90%. In order to study the preservation of the polarization during the ion motion through the magnetic system of the ring, the concept of the instantaneous quantization axis is introduced. It is suggested that the employment of “Siberian snakes” may help to preserve the ion beam polarization in the ring. The control of the beam polarization can be achieved by different methods: by measuring the Stokes parameters for the emitted photons or by observing the angular dependence of the transition rates for polarized ions. The important motivation for the production of polarized ion beams is the possibility to observe parity nonconservation effects in the hyperfine-quenched transitions in helium-like highly charged ions, where these effects can reach an unprecedented high value for atomic physics. The possible observation of parity nonconservation effects connected with the nuclear anapole moment is also discussed. A method for the observation of the electric dipole moment of an electron in a storage ring with a polarized highly charged ion beam is proposed. This method allows, in principle, to improve the existing boundaries for the electric dipole moment of an electron. However, the requirements of the corresponding experiment are very stringent. [Copyright &y& Elsevier]

Abstract: This paper presents a comparative study on locally mass-conservative numerical methods for Darcy''s flows. The classical mixed finite element method (MFEM) is compared with the newly developed discontinuous finite volume method (DFVM) with and without weak over-penalization (WOP). These numerical methods are tested on three representative problems in porous media flows. In particular, locality, accuracy of numerical solutions, computational costs, and implementation issues are examined. The study indicates that the discontinuous finite volume methods could be viable alternatives to the classical mixed finite element method for Darcy''s flows. [Copyright &y& Elsevier]

We discuss the prospects for parity violation experiments in atomic hydrogen and deuterium to contribute to testing the Standard Model (SM). We find that, if parity experiments in hydrogen can be done, they remain highly desirable because there is negligible atomic-physics uncertainty and low energy tests of weak neutral current interactions are needed to probe for new physics beyond the SM. Analysis of a generic APV experiment in deuterium indicates that a 0.3% measurement of C requires development of a slow (77K) metastable beam of ≈ 5×10D(2S) s per hyperfine component. The advent of UV radiation from free electron laser (FEL) technology could allow production of such a beam. [ABSTRACT FROM AUTHOR]

Accurate theoretical knowledge of the (1s2p)3P1-(1s2s)1S0 splitting in He-like ions is demanded for future experimental studies of the nuclear spin-dependent part of the weak interaction. In this paper we perform a calculation of the hyperfine structure of (1s2p)3P1-(1s2s)1S0 within 3 ≤ Z ≤ 35, Z being the atomic number. In this Z range parity nonconservation (PNC) effects are amplified by the close energy proximity of the opposite parity levels (1s2p)3P1 and (1s2s)1S0. We find that the hyperfine structure is relevant for Z > 12, and produces splitting among the hyperfine sublevels as large as 150 meV for medium Z He-like ions (Z ~ 35). Nous avons besoin de connaissances théoriques précises concernant la séparation en énergie du (1s2p) 3P1-(1s2s) 1S0 dans les ions de type He pour pouvoir étudier dans l'avenir la partie de l'interaction faible qui dépend du spin nucléaire. Ici, nous complétons un calcul théorique de la structure hyperfine de (1s2p) 3P1-(1s2s) 1S0 pour des valeurs du nombre atomique Z dans le domaine 3 ≤ Z ≤ 35. Dans ce domaine, les effets de non conservation de la parité (PNC) sont amplifiés par la proximité des niveaux de parité opposée (1s2p) 3P1 et (1s2s) 1S0. Nous trouvons que la structure hyperfine est intéressante pour Z > 12 et produit des séparations parmi les sous-niveaux hyperfins aussi larges que 150 meV pour des ions de type He de Z intermédiaires (Z ~ 35). [ABSTRACT FROM AUTHOR]

Copyright of European Journal of Population is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A hierarchy of new nonlinear evolution equations associated with a 3×3 matrix spectral problem with two potentials is derived and its Hamiltonian structures are established with the aid of trace identity. The negative flow of the hierarchy is then discussed. A reduction of this hierarchy and its Hamiltonian structures are constructed. An infinite sequence of conserved quantities of several new soliton equations is obtained. [ABSTRACT FROM AUTHOR]

The presence of error floor in low density parity check (LDPC) codes is of great concern for potential applications of LDPC codes to data storage channels, which require the code to maintain the near capacity error correcting performance down to frame error rates of 10-12. In order to investigate the error floor of LDPC codes under magnetic recording channels used in data storage systems, we extended the trapping set based estimation method to predict the error floor under magnetic recording channels. The goal is to accurately estimate the error rates in the error floor region for certain types of LDPC codes under the partial response channel. First, we use field-programmable gate array (FPGA) hardware simulation to find the trapping sets that cause the decoding failure in the error floor region. For each trapping set, we extract the parameters that are key to the decoding failure caused by this trapping set. Then we use a much simpler in situ simulation with these parameters to obtain the conditional decoding failure rate. By considering all the trapping sets, we obtain the overall frame error rate in the error floor region. The estimation results under the magnetic recording channel are within 0.3 dB of the direct simulation results. [ABSTRACT FROM AUTHOR]

Recently, 32 k-bit sector size for hard disk drives is being investigated to take advantage of the superior performance of long error correcting codes. Meanwhile, low-density parity-check (LDPC) codes have been actively investigated for obtaining coding gains over conventional Reed-Solomon (RS) codes mainly for 4 k-bit sectors. In this paper, the coding gain of a 32 k-bit LDPC code over a 4 k-bit LDPC code, a 32 k-bit RS code, and a 4 k-bit RS code in magnetic recording channels is investigated. The decoding complexity of 32 k-bit LDPC codes and 4 k-bit LDPC codes is also discussed. It is important to evaluate whether the coding gains are enough to justify the increased complexity. Using the 32 k-bit LDPC code, 0.8-dB gain over the 32 k-bit RS code or the 4 k-bit LDPC code (the two schemes coincidentally showed similar performance) at 32 k-bit block error rate (BLER)10-3, and 1.6-dB gain over the 4 k-bit RS code were obtained. It is shown that 32 k-bit LDPC codes require a larger number of iterations than the 4 k-bit LDPC codes. It is also shown that there is much room to improve the design of 32 k-bit LDPC codes than the code used in the simulation. To illustrate the potential, quasicyclic LDPC codes with column weights up to 13 with girth 6 are investigated. [ABSTRACT FROM AUTHOR]

In this paper, we investigate RS plus LDPC concatenated architectures for perpendicular magnetic recording channels. Using simulations, we find the optimal code rate and iterative scheme for the concatenated codes, compare their performance in both random noise and media defects, and show that those whose inner LDPC codes have lower column weights exhibit better performance. In addition, we estimate the performance of the concatenated codes with inner LDPC codes of column weight two, at very high signal-to-noise ratios, and find their error floors. [ABSTRACT FROM AUTHOR]

Two-dimensional magnetic recording (TDMR) is a new magnetic recording paradigm that aims to record one bit of information in one or a few grains, with the goal of achieving a recording density of nearly 10 Tbit/in². In addition to the usual noise, a TDMR channel experiences the problem that some bits are never recorded because of the randomness of grain size and location. Thus, it is believed that a key component of a TDMR channel is two-dimensional (2-D) signal processing along with a strong error correction code. In this study, the TDMR channel is investigated based on a random Voronoi grain model and a signal processing architecture is proposed. Here, a 2-D linear minimum mean squared error (LMMSE) equalizer and a low-density parity-check (LDPC) code are employed and the effects of unwritten bits are modeled by a Gaussian mixture model. In numerical simulations, the proposed architecture shows the feasibility of user bit densities near 10 Tbit/in² for media with a 20 Tgrains/in² grain density. [ABSTRACT FROM AUTHOR]

We discuss the asymptotic structure of null infinity in five dimensional space-times. Since it is known that the conformal infinity is not useful for odd higher dimensions, we shall employ the coordinate based method such as the Bondi coordinate first introduced in four dimensions. Then we will define the null infinity and identify the asymptotic symmetry. We will also derive the Bondi mass expression and show its conservation law. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new implementation of the Extended Min-Sum (EMS) decoder for non-binary LDPC codes. A particularity of the new algorithm is that it takes into accounts the memory problem of the non-binary LDPC decoders, together with a significant complexity reduction per decoding iteration. The key feature of our decoder is to truncate the vector messages of the decoder to a limited number nm of values in order to reduce the memory requirements. Using the truncated messages, we propose an efficient implementation of the EMS decoder which reduces the order of complexity to O(nm log2 nm). This complexity starts to be reasonable enough to compete with binary decoders. The performance of the low complexity algorithm with proper compensation is quite good with respect to the important complexity reduction, which is shown both with a simulated density evolution approach and actual simulations. [ABSTRACT FROM AUTHOR]

In a recent paper, Calkin et al. [N. Calkin, N. Drake, K. James, S. Law, P. Lee, D. Penniston and J. Radder, 'Divisibility properties of the 5-regular and 13-regular partition functions', Integers 8 (2008), #A60] used the theory of modular forms to examine 5-regular partitions modulo 2 and 13-regular partitions modulo 2 and 3; they obtained and conjectured various results. In this note, we use nothing more than Jacobi's triple product identity to obtain results for 5-regular partitions that are stronger than those obtained by Calkin and his collaborators. We find infinitely many Ramanujan-type congruences for b5.n/, and we prove the striking result that the number of 5-regular partitions of the number n is even for at least 75% of the positive integers n. [ABSTRACT FROM AUTHOR]

Abstract: We show that R-parity violating decay of Wino dark matter of mass about 3 TeV can naturally account for the flux and spectral shape of the cosmic-ray electrons and positrons observed by the PAMELA and Fermi satellites. To provide a theoretical basis for the scenario, we present a model in which trilinear R-parity breaking appears with a coefficient suppressed by powers of the gravitino mass, which naturally leads to the Wino lifetime of . [Copyright &y& Elsevier]

Abstract: Glozman has proposed that highly excited mesons and baryons fall into parity doublets, and that the on the leading Regge trajectory should have a nearly degenerate partner. A re-analysis of Crystal Barrel data does not support this idea. A likely explanation is that centrifugal barriers on the leading trajectory allow formation of the states, but are too strong to allow states. Two new polarisation experiments have the potential for major progress in meson spectroscopy. [Copyright &y& Elsevier]

It is well-known that the domains of static stability and dynamic stability (even for a linear approach) do not match each other when the system is no more conservative and the dynamic approach is usually privileged, meaning that the dynamic stability domain is included in the static one. Following previous works proposing a new criterion of static stability of nonconservative systems and prolonging a paper of Gallina devoted to linear dynamic instability (flutter), we show in this paper some remarkable relations between the two approaches: contrary to the common thought, the new static stability criterion implies partially the dynamic one. [ABSTRACT FROM AUTHOR]

In this paper low-density parity-check (LDPC) codes are designed for burst erasure channels. Firstly, lower bounds for the maximum length erasure burst that can always he corrected with message-passing decoding are derived as a function of the parity-check matrix properties. We then show how parity-cheek matrices for burst erasure correcting LDPC codes can be constructed using superposition, where the burst erasure correcting performance of the resulting codes is derived as a property of the stopping set size of the base matrices and the choice of permutation matrices for the superposition. This result is then used to design both single burst erasure correcting LDPC codes which are also resilient to the presence of random erasures in the received hits and LDPC codes which can correct multiple erasure bursts in the same codeword. [ABSTRACT FROM AUTHOR]

In this paper, we present a novel pragmatic approach, referred to as detection b multiple trellises, to perform trellis-based detection over realistic channels. More precisely, we consider channels with unknown parameters and apply the concept of detection by multiple trellises to forward-backward (FB) algorithms. The key idea of our approach consists, first, of property quantizing the channel parameters and, then, considering replication of coherent FB algorithms operating on parallel trellises, one per hypothetical quantized value. In order to make the receiver robust against a possibly time-varying channel parameters, the proposed soft-output algorithms perform a proper "manipulation" of the forward sod backward metrics computed by the parallel FB algorithms at regularly spaced trellis steps. We consider two significant examples of application: detection over (i) phase-uncertain channels and (ii) fading channels. The performance of the proposed algorithm is investigated considering differentially encoded (DE) quaternary phase shift keying (QPSK) and iterative detection schemes based on tow-density parity-check (LDPC) codes. Besides having a too complexity, the proposed soft-output algorithms turn out to be robust, flexible, blind, in the sense that no knowledge of the channel parameter statistics is required, and highly parallelizable, as it is desirable in high-throughput future wireless communication systems. [ABSTRACT FROM AUTHOR]

In this letter, a tow complexity decoding algorithm for binary linear block codes is applied to low-density parity-check (LDPC) codes and improvements are described, namely an extension to soft-decision decoding and a loop detection mechanism. For soft decoding, only one real-valued addition per code symbol is needed, while the remaining operations are only binary as in the hard decision case. The decoding performance is considerably increased by the loop detection. Simulation results are used to compare the performance with other known decoding strategies for LDPC codes, with the result that the presented algorithms offer excellent performances at smaller complexity. [ABSTRACT FROM AUTHOR]

We present a detailed study on the possibility of manipulating quantum information encoded in the 'radial' modes of arrays of trapped ions (i.e. in the ions' oscillations orthogonal to the trap's main axis). In such systems, because of the tightness of transverse confinement, the radial modes pertaining to different ions can be addressed individually. In the first part of the paper we show that, if local control of the radial trapping frequencies is available, any linear optical and squeezing operation on the locally defined modes—on single as well as on many modes—can be reproduced by manipulating the frequencies. Then, we proceed to describe schemes apt to generate unprecedented degrees of bipartite and multipartite continuous variable (CV) entanglement under realistic noisy working conditions and even restricting only to a global control of the trapping frequencies. Furthermore, we consider the transmission of the quantum information encoded in the radial modes along the array of ions, and show it to be possible to a remarkable degree of accuracy, for both finite-dimensional and CV quantum states. Finally, as an application, we show that the states which can be generated in this setting allow for the violation of multipartite non-locality tests, by feasible displaced parity measurements. Such a demonstration would be a first test of quantum non-locality for 'massive' degrees of freedom (i.e. for degrees of freedom describing the motion of massive particles). [ABSTRACT FROM AUTHOR]

The number of known elementary particles is now very large, and to redude their diverse properties to order it is useful to look for symmetries between them. Symmetry properties of various kinds, and the conservation laws associated with them, are discussed here. After giving a brief survey of the general types of particle encountered in nature, we discuss first the symmetries related to space and time, and associated with the conservation laws of momentum, energy momentum, and parity. Later we discuss the so-called internal symmetries, in which different particles are regarded as different states of a single basic entity. Theories of this type - particularly the 'eightfold way' - have had considerable success in systematizing the properties of the known particles. [ABSTRACT FROM AUTHOR]

The role of the band quantum number K in influencing the character of allowed $ \beta$ transitions in heavy deformed nuclei is examined. The conditions for the occurrence of K -forbidden decays in this region are explored. Specific cases of “allowed” $ \beta$ decays proceeding via $ \Delta$ K = 2 to $ \Delta$ K = 6 channels are presented to illustrate the phenomenon. The listed $ \Delta$ K = 2 transitions, which by themselves contribute over 10% of all the presently known allowed transitions for A $ \geq$ 228 nuclei, are seen to have an average $\ensuremath\log ft \geq 9.0$ , which is clearly outside the normal range for allowed transitions. It is concluded that, wherever the $ \beta$ -connected states can be confidently labelled using the $\ensuremath I^{\pi}K$ quantum numbers, the K -forbiddenness is in general as significant as that involving the other two (spin and parity) quantum numbers. [ABSTRACT FROM AUTHOR]

We study polarization variables in the photoproduction of $ \omega$ -mesons with subsequent $ \omega$ → $ \gamma$ $ \pi^{0}_{}$ decay. Single and double polarization observables are calculated as a function of different final-state angles. Reaction models include pomeron (natural parity) and $ \pi^{0}_{}$ (unnatural parity) exchange in the t -channel. In addition, the contribution of s -channel resonances is considered. The sensitivity of the polarization observables to the reaction dynamics is discussed. [ABSTRACT FROM AUTHOR]

For a compact charged medium interacting with an intrinsic electromagnetic field, the local and integral conservation laws along trajectories are investigated. Properties of a stationary compact beam torus are discussed. [ABSTRACT FROM AUTHOR]

Abstract: We show that a precise measurement of the single-top production cross section at the Tevatron and the LHC can strongly constrain the model parameters of the Littlest Higgs model with T-parity. A reduction in the single-top production rate from the Standard Model prediction implies new physics phenomena generated by the heavy T-parity partners of the top quark. We show that the degree of polarization of the top quark produced from the decay of its heavy T-odd partner () can be utilized to determine the new physics energy scale, and the mass of can be measured from the missing transverse momentum distribution in the event. [Copyright &y& Elsevier]

Abstract: We study the cosmology of two versions of supersymmetric Left–Right symmetric model. The scale of the symmetry breaking in these models is naturally low, . Spontaneous breakdown of parity is accompanied by a first order phase transition. We simulate the domain walls of the phase transition and show that they provide requisite conditions, specifically, CP violating phase needed for leptogenesis. Additionally soft resonant leptogenesis is conditionally viable in the two models considered. Some of the parameters in the soft supersymmetry breaking terms are shown to be constrained from these considerations. It is argued that the models may be testable in upcoming collider and cosmology experiments. [Copyright &y& Elsevier]