WorldWideScience

Sample records for chirality

  1. Chiral photochemistry

    CERN Document Server

    Inoue, Yoshihisa

    2004-01-01

    Direct Asymmetric Photochemistry with Circularly Polarized Light, H. RauCoherent Laser Control of the Handedness of Chiral Molecules, P. Brumer and M. ShapiroMagnetochiral Anisotropy in Asymmetric Photochemistry, G.L.J.A.RikkenEnantiodifferentiating Photosensitized Reactions, Y. InoueDiastereodifferentiating Photoreactions, N. Hoffmann and J.-P. PeteChirality in Photochromism, Y. Yokoyama and M. SaitoChiral Photochemistry with Transition Metal Complexes, S. Sakaki and T. HamadaTemplate-Induced Enantioselective Photochemical Reactions in S

  2. Chiral Electronics

    OpenAIRE

    Kharzeev, Dmitri E.; Yee, Ho-Ung

    2012-01-01

    We consider the properties of electric circuits involving Weyl semimetals. The existence of the anomaly-induced chiral magnetic current in a Weyl semimetal subjected to magnetic field causes an interesting and unusual behavior of such circuits. We consider two explicit examples: i) a circuit involving the "chiral battery" and ii) a circuit that can be used as a "quantum amplifier" of magnetic field. The unique properties of these circuits stem from the chiral anomaly and may be utilized for c...

  3. Chiral superconductors

    Science.gov (United States)

    Kallin, Catherine; Berlinsky, John

    2016-05-01

    Chiral superconductivity is a striking quantum phenomenon in which an unconventional superconductor spontaneously develops an angular momentum and lowers its free energy by eliminating nodes in the gap. It is a topologically non-trivial state and, as such, exhibits distinctive topological modes at surfaces and defects. In this paper we discuss the current theory and experimental results on chiral superconductors, focusing on two of the best-studied systems, Sr2RuO4, which is thought to be a chiral triplet p-wave superconductor, and UPt3, which has two low-temperature superconducting phases (in zero magnetic field), the lower of which is believed to be chiral triplet f-wave. Other systems that may exhibit chiral superconductivity are also discussed. Key signatures of chiral superconductivity are surface currents and chiral Majorana modes, Majorana states in vortex cores, and the possibility of half-flux quantum vortices in the case of triplet pairing. Experimental evidence for chiral superconductivity from μSR, NMR, strain, polar Kerr effect and Josephson tunneling experiments are discussed.

  4. Isotopic chirality

    Energy Technology Data Exchange (ETDEWEB)

    Floss, H.G. [Univ. of Washington, Seattle, WA (United States)

    1994-12-01

    This paper deals with compounds that are chiral-at least in part, due to isotope substitution-and their use in tracing the steric course of enzyme reaction in vitro and in vivo. There are other applications of isotopically chiral compounds (for example, in analyzing the steric course of nonenzymatic reactions and in probing the conformation of biomolecules) that are important but they will not be discussed in this context.

  5. Punctuated Chirality

    Science.gov (United States)

    Gleiser, Marcelo; Thorarinson, Joel; Walker, Sara Imari

    2008-12-01

    Most biomolecules occur in mirror, or chiral, images of each other. However, life is homochiral: proteins contain almost exclusively L-amino acids, while only D-sugars appear in RNA and DNA. The mechanism behind this fundamental asymmetry of life remains an open problem. Coupling the spatiotemporal evolution of a general autocatalytic polymerization reaction network to external environmental effects, we show through a detailed statistical analysis that high intensity and long duration events may drive achiral initial conditions towards chirality. We argue that life’s homochirality resulted from sequential chiral symmetry breaking triggered by environmental events, thus extending the theory of punctuated equilibrium to the prebiotic realm. Applying our arguments to other potentially life-bearing planetary platforms, we predict that a statistically representative sampling will be racemic on average.

  6. Punctuated Chirality

    CERN Document Server

    Gleiser, Marcelo; Walker, Sara Imari

    2008-01-01

    Most biomolecules occur in mirror, or chiral, images of each other. However, life is homochiral: proteins contain almost exclusively levorotatory (L) amino acids, while only dextrorotatory (R) sugars appear in RNA and DNA. The mechanism behind this fundamental asymmetry of life remains an open problem. Coupling the spatiotemporal evolution of a general autocatalytic polymerization reaction network to external environmental effects, we show through a detailed statistical analysis that high intensity and long duration events may drive achiral initial conditions towards chirality. We argue that life's homochirality resulted from sequential chiral symmetry breaking triggered by environmental events, thus extending the theory of punctuated equilibrium to the prebiotic realm. Applying our arguments to other potentially life-bearing planetary platforms, we predict that a statistically representative sampling will be racemic on average.

  7. Chiral morphing

    CERN Document Server

    Chang, N P

    1994-01-01

    Chiral symmetry undergoes a metamorphosis at T.sub(c). For T < T.sub(c), the usual Noether charge, \\Qa, is dynamically broken by the vacuum. Above T.sub(c), chiral symmetry undergoes a subtle change, and the Noether charge \\underline{{\\em morphs}} into \\Qbeta, with the thermal vacuum now becoming invariant under \\Qbeta. This vacuum is however not invariant under the old \\Qa transformations. As a result, the pion remains strictly massless at high T. The pion propagates in the early universe with a halo. New order parameters are proposed to probe the structure of the new thermal vacuum.

  8. Chiral transparency

    International Nuclear Information System (INIS)

    Color transparency is the vanishing of initial and final state interactions, predicted by QCD to occur in high momentum transfer quasielastic nuclear reactions. For specific reactions involving nucleons, the initial and final state interactions are expected to be dominated by exchanges of pions. We argue that these interactions are also suppressed in high momentum transfer nuclear quasielastic reactions; this is open-quotes chiral transparency.close quotes We show that studies of the e3He→e'Δ++nn reaction could reveal the influence of chiral transparency. copyright 1997 The American Physical Society

  9. Chiral Nanoscience and Nanotechnology

    OpenAIRE

    Dibyendu S. Bag; T.C. Shami; K.U. Bhasker Rao

    2008-01-01

    The paper reviews nanoscale science and technology of chiral molecules/macromolecules-under twosubtopics-chiral nanotechnology and nano-chiral technology. Chiral nanotechnology discusses thenanotechnology, where molecular chirality plays a role in the properties of materials, including molecularswitches, molecular motors, and other molecular devices; chiral supramolecules and self-assembled nanotubesand their functions are also highlighted. Nano-chiral technology  describes the nanoscale appr...

  10. Chiral symmetry

    International Nuclear Information System (INIS)

    We present many varied chiral symmetry models at the quark level which consistently describe strong interaction hadron dynamics. The pattern that emerges is a nonstrange current quark mass scale mcur ≅ (34-69) MeV and a current quark mass ratio (ms/m)cur ≅ 5-6 along with no strange quark content in nucleons. (orig./WL)

  11. Punctuated Chirality

    OpenAIRE

    Gleiser, Marcelo; Thorarinson, Joel; Walker, Sara Imari

    2008-01-01

    Most biomolecules occur in mirror, or chiral, images of each other. However, life is homochiral: proteins contain almost exclusively levorotatory (L) amino acids, while only dextrorotatory (R) sugars appear in RNA and DNA. The mechanism behind this fundamental asymmetry of life remains an open problem. Coupling the spatiotemporal evolution of a general autocatalytic polymerization reaction network to external environmental effects, we show through a detailed statistical analysis that high int...

  12. Chiral streamers

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Dandan; Cao, Xin [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Lu, Xinpei, E-mail: luxinpei@hotmail.com [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240 (China); Ostrikov, Kostya [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, Queensland 4000 (Australia); Comonwealth Scientific and Industrial Research Organization, P.O. Box 218, Sydney, New South Wales 2070 (Australia)

    2015-10-15

    The interaction of time-varying electromagnetic fields and solid, liquid, and gaseous matter may lead to electrical breakdown phenomena through the excitation of ionization waves or streamers that control the dynamics of localized plasma propagation through the media. The streamers usually propagate along straight lines, either between random points in space or along a certain direction in a guided mode. Here, we report on a new type of plasma discharges with the regular helical propagation pattern driven by a pulsed dc voltage in nitrogen at sub-atmospheric-pressure conditions. The helical guided streamers, named chiral streamers or chi-streamers, are excited without any external magnetic fields, which commonly cause helical plasma motions. We also demonstrate a hybrid propagation mode involving the interchangeable chiral streamers and the straight-line propagating plasmas. High-speed, time-resolved optical imaging reveals that the chiral streamers and the hybrid patterns are made of spatially localized discrete plasma bullets, similar to the straight-line guided streamers. These results may enable effective control of propagation of confined plasmas and electromagnetic energy along pre-determined, potentially deterministic paths, which have important implications for the development of next-generation plasma-based radiation sources, communication devices, and medical treatments.

  13. Chiral streamers

    Science.gov (United States)

    Zou, Dandan; Cao, Xin; Lu, Xinpei; Ostrikov, Kostya Ken

    2015-10-01

    The interaction of time-varying electromagnetic fields and solid, liquid, and gaseous matter may lead to electrical breakdown phenomena through the excitation of ionization waves or streamers that control the dynamics of localized plasma propagation through the media. The streamers usually propagate along straight lines, either between random points in space or along a certain direction in a guided mode. Here, we report on a new type of plasma discharges with the regular helical propagation pattern driven by a pulsed dc voltage in nitrogen at sub-atmospheric-pressure conditions. The helical guided streamers, named chiral streamers or chi-streamers, are excited without any external magnetic fields, which commonly cause helical plasma motions. We also demonstrate a hybrid propagation mode involving the interchangeable chiral streamers and the straight-line propagating plasmas. High-speed, time-resolved optical imaging reveals that the chiral streamers and the hybrid patterns are made of spatially localized discrete plasma bullets, similar to the straight-line guided streamers. These results may enable effective control of propagation of confined plasmas and electromagnetic energy along pre-determined, potentially deterministic paths, which have important implications for the development of next-generation plasma-based radiation sources, communication devices, and medical treatments.

  14. Chiral geometry in multiple chiral doublet bands

    CERN Document Server

    Zhang, Hao

    2015-01-01

    The chiral geometry of the multiple chiral doublet bands with identical configuration is discussed for different triaxial deformation parameters $\\gamma$ in the particle rotor model with $\\pi h_{11/2}\\otimes \

  15. Chiral symmetry and chiral-symmetry breaking

    International Nuclear Information System (INIS)

    These lectures concern the dynamics of fermions in strong interaction with gauge fields. Systems of fermions coupled by gauge forces have a very rich structure of global symmetries, which are called chiral symmetries. These lectures will focus on the realization of chiral symmetries and the causes and consequences of thier spontaneous breaking. A brief introduction to the basic formalism and concepts of chiral symmetry breaking is given, then some explicit calculations of chiral symmetry breaking in gauge theories are given, treating first parity-invariant and then chiral models. These calculations are meant to be illustrative rather than accurate; they make use of unjustified mathematical approximations which serve to make the physics more clear. Some formal constraints on chiral symmetry breaking are discussed which illuminate and extend the results of our more explicit analysis. Finally, a brief review of the phenomenological theory of chiral symmetry breaking is presented, and some applications of this theory to problems in weak-interaction physics are discussed

  16. Chiral mirrors

    Energy Technology Data Exchange (ETDEWEB)

    Plum, Eric, E-mail: erp@orc.soton.ac.uk [Optoelectronics Research Centre and Centre for Photonic Metamaterials, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Zheludev, Nikolay I., E-mail: niz@orc.soton.ac.uk [Optoelectronics Research Centre and Centre for Photonic Metamaterials, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); The Photonics Institute and Centre for Disruptive Photonic Technologies, Nanyang Technological University, Singapore 637378 (Singapore)

    2015-06-01

    Mirrors are used in telescopes, microscopes, photo cameras, lasers, satellite dishes, and everywhere else, where redirection of electromagnetic radiation is required making them arguably the most important optical component. While conventional isotropic mirrors will reflect linear polarizations without change, the handedness of circularly polarized waves is reversed upon reflection. Here, we demonstrate a type of mirror reflecting one circular polarization without changing its handedness, while absorbing the other. The polarization-preserving mirror consists of a planar metasurface with a subwavelength pattern that cannot be superimposed with its mirror image without being lifted out of its plane, and a conventional mirror spaced by a fraction of the wavelength from the metasurface. Such mirrors enable circularly polarized lasers and Fabry-Pérot cavities with enhanced tunability, gyroscopic applications, polarization-sensitive detectors of electromagnetic waves, and can be used to enhance spectroscopies of chiral media.

  17. Chiral Gravitational Waves from Chiral Fermions

    CERN Document Server

    Anber, Mohamed M

    2016-01-01

    We report on a new mechanism that leads to the generation of primordial chiral gravitational waves, and hence, the violation of the parity symmetry in the Universe. We show that nonperturbative production of fermions with a definite helicity is accompanied by the generation of chiral gravitational waves. This is a generic and model-independent phenomenon that can occur during inflation, reheating and radiation eras, and can leave imprints in the cosmic microwave background polarization and may be observed in future ground- and space-based interferometers. We also discuss a specific model where chiral gravitational waves are generated via the production of light chiral fermions during pseudoscalar inflation.

  18. Anomalous Chiral Superfluidity

    OpenAIRE

    Lublinsky, Michael(Physics Department, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel); Zahed, Ismail

    2009-01-01

    We discuss both the anomalous Cartan currents and the energy-momentum tensor in a left chiral theory with flavour anomalies as an effective theory for flavored chiral phonons in a chiral superfluid with the gauged Wess-Zumino-Witten term. In the mean-field (leading tadpole) approximation the anomalous Cartan currents and the energy momentum tensor take the form of constitutive currents in the chiral superfluid state. The pertinence of higher order corrections and the Adler-Bardeen theorem is ...

  19. Introduction to chiral symmetry

    International Nuclear Information System (INIS)

    These lectures are an attempt to a pedagogical introduction into the elementary concepts of chiral symmetry in nuclear physics. Effective chiral models such as the linear and nonlinear sigma model will be discussed as well as the essential ideas of chiral perturbation theory. Some applications to the physics of ultrarelativistic heavy ion collisions will be presented

  20. Baryons and Chiral Symmetry

    CERN Document Server

    Liu, Keh-Fei

    2016-01-01

    The relevance of chiral symmetry in baryons is highlighted in three examples in the nucleon spectroscopy and structure. The first one is the importance of chiral dynamics in understanding the Roper resonance. The second one is the role of chiral symmetry in the lattice calculation of $\\pi N \\sigma$ term and strangeness. The third one is the role of chiral $U(1)$ anomaly in the anomalous Ward identity in evaluating the quark spin and the quark orbital angular momentum. Finally, the chiral effective theory for baryons is discussed.

  1. Chirality in Nonlinear Optics

    Science.gov (United States)

    Haupert, Levi M.; Simpson, Garth J.

    2009-05-01

    The past decade has witnessed the emergence of new measurement approaches and applications for chiral thin films and materials enabled by the observations of the high sensitivity of second-order nonlinear optical measurements to chirality. In thin films, the chiral response to second harmonic generation and sum frequency generation (SFG) from a single molecular monolayer is often comparable with the achiral response. The chiral specificity also allows for symmetry-allowed SFG in isotropic chiral media, confirming predictions made ˜50 years ago. With these experimental demonstrations in hand, an important challenge is the construction of intuitive predictive models that allow the measured chiral response to be meaningfully related back to molecular and macromolecular structure. This review defines and considers three distinct mechanisms for chiral effects in uniaxially oriented assemblies: orientational chirality, intrinsic chirality, and isotropic chirality. The role of each is discussed in experimental and computational studies of bacteriorhodopsin films, binaphthol, and collagen. Collectively, these three model systems support a remarkably simple framework for quantitatively recovering the measured chiral-specific activity.

  2. Chiral Rotational Spectroscopy

    CERN Document Server

    Cameron, Robert P; Barnett, Stephen M

    2015-01-01

    We introduce chiral rotational spectroscopy: a new technique that enables the determination of the individual optical activity polarisability components $G_{XX}'$, $G_{YY}'$, $G_{ZZ}'$, $A_{X,YZ}$, $A_{Y,ZX}$ and $A_{Z,XY}$ of chiral molecules, in a manner that reveals the enantiomeric constitution of a sample whilst yielding an incisive signal even for a racemate. Chiral rotational spectroscopy could find particular use in the analysis of molecules that are chiral by virtue of their isotopic constitution and molecules with multiple chiral centres. The principles that underpin chiral rotational spectroscopy can also be exploited in the search for molecular chirality in space, which, if found, may add weight to hypotheses that biological homochirality and indeed life itself are of cosmic origin.

  3. On chiral and non chiral 1D supermultiplets

    Energy Technology Data Exchange (ETDEWEB)

    Toppan, Francesco, E-mail: toppan@cbpf.b [Centro Brasileiro de Pesquisas Fisicas (TEO/CBPF), Rio de Janeiro, RJ (Brazil). Coordenacao de Fisica Teorica

    2011-07-01

    In this talk I discuss and clarify some issues concerning chiral and non chiral properties of the one-dimensional supermultiplets of the N-extended supersymmetry. Quaternionic chirality can be defined for N = 4, 5, 6, 7, 8. Octonionic chirality for N = 8 and beyond. Inequivalent chiralities only arise when considering several copies of N = 4 or N = 8 supermultiplets. (author)

  4. Chiral symmetry and chiral-symmetry breaking

    Energy Technology Data Exchange (ETDEWEB)

    Peskin, M.E.

    1982-12-01

    These lectures concern the dynamics of fermions in strong interaction with gauge fields. Systems of fermions coupled by gauge forces have a very rich structure of global symmetries, which are called chiral symmetries. These lectures will focus on the realization of chiral symmetries and the causes and consequences of thier spontaneous breaking. A brief introduction to the basic formalism and concepts of chiral symmetry breaking is given, then some explicit calculations of chiral symmetry breaking in gauge theories are given, treating first parity-invariant and then chiral models. These calculations are meant to be illustrative rather than accurate; they make use of unjustified mathematical approximations which serve to make the physics more clear. Some formal constraints on chiral symmetry breaking are discussed which illuminate and extend the results of our more explicit analysis. Finally, a brief review of the phenomenological theory of chiral symmetry breaking is presented, and some applications of this theory to problems in weak-interaction physics are discussed. (WHK)

  5. Understanding complex chiral plasmonics

    Science.gov (United States)

    Duan, Xiaoyang; Yue, Song; Liu, Na

    2015-10-01

    Chiral nanoplasmonics exhibits great potential for novel nanooptical devices due to the generation of a strong chiroptical response within nanoscale metallic structures. Recently, a number of different approaches have been utilized to create chiral nanoplasmonic structures. However, particularly for tailoring nanooptical chiral sensing devices, the understanding of the resulting chiroptical response when coupling chiral and achiral structures together is crucial and has not been completely understood to date. Here, we present a thorough and step-by-step experimental study to understand the intriguing chiral-achiral coupling scheme. We set up a hybrid plasmonic system, which bears resemblance to the `host-guest' system in supramolecular chemistry to analyze and explain the complex chiral response both at the chiral and achiral plasmonic resonances. We also provide an elegant and simple analytical model, which can describe, predict, and comprehend the chiroptical spectra in detail. Our study will shed light on designing well-controlled chiral-achiral coupling platforms for reliable chiral sensing.Chiral nanoplasmonics exhibits great potential for novel nanooptical devices due to the generation of a strong chiroptical response within nanoscale metallic structures. Recently, a number of different approaches have been utilized to create chiral nanoplasmonic structures. However, particularly for tailoring nanooptical chiral sensing devices, the understanding of the resulting chiroptical response when coupling chiral and achiral structures together is crucial and has not been completely understood to date. Here, we present a thorough and step-by-step experimental study to understand the intriguing chiral-achiral coupling scheme. We set up a hybrid plasmonic system, which bears resemblance to the `host-guest' system in supramolecular chemistry to analyze and explain the complex chiral response both at the chiral and achiral plasmonic resonances. We also provide an elegant

  6. Chiral Superfluidity for QCD

    CERN Document Server

    Kalaydzhyan, Tigran

    2014-01-01

    We argue that the strongly coupled quark-gluon plasma formed at LHC and RHIC can be considered as a chiral superfluid. The "normal" component of the fluid is the thermalized matter in common sense, while the "superfluid" part consists of long wavelength (chiral) fermionic states moving independently. We use the bosonization procedure with a finite cut-off and obtain a dynamical axion-like field out of the chiral fermionic modes. Then we use relativistic hydrodynamics for macroscopic description of the effective theory obtained after the bosonization. Finally, solving the hydrodynamic equations in gradient expansion, we find that in the presence of external electromagnetic fields or rotation the motion of the "superfluid" component gives rise to the chiral magnetic, chiral vortical, chiral electric and dipole wave effects. Latter two effects are specific for a two-component fluid, which provides us with crucial experimental tests of the model.

  7. Mechanical separation of chiral dipoles by chiral light

    CERN Document Server

    Canaguier-Durand, Antoine; Genet, Cyriaque; Ebbesen, Thomas W

    2013-01-01

    Optical forces take on a specific form when involving chiral light fields interacting with chiral objects. We show that optical chirality density and flow can have mechanical effects through reactive and dissipative components of chiral forces exerted on chiral dipoles. Remarkably, these force components are directly related to standard observables: optical rotation and circular dichroism, respectively. As a consequence, resulting forces and torques are dependent on the enantiomeric form of the chiral dipole. This leads to promising strategies for the mechanical separation of chiral objects using chiral light forces.

  8. Doped Chiral Polymer Metamaterials Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Doped Chiral Polymer Metamaterials (DCPM) with tunable resonance frequencies have been developed by adding plasmonic inclusions into chiral polymers with variable...

  9. Chiral geometry in multiple chiral doublet bands

    Science.gov (United States)

    Zhang, Hao; Chen, Qibo

    2016-02-01

    The chiral geometry of multiple chiral doublet bands with identical configuration is discussed for different triaxial deformation parameters γ in the particle rotor model with . The energy spectra, electromagnetic transition probabilities B(M1) and B(E2), angular momenta, and K-distributions are studied. It is demonstrated that the chirality still remains not only in the yrast and yrare bands, but also in the two higher excited bands when γ deviates from 30°. The chiral geometry relies significantly on γ, and the chiral geometry of the two higher excited partner bands is not as good as that of the yrast and yrare doublet bands. Supported by Plan Project of Beijing College Students’ Scientific Research and Entrepreneurial Action, Major State 973 Program of China (2013CB834400), National Natural Science Foundation of China (11175002, 11335002, 11375015, 11461141002), National Fund for Fostering Talents of Basic Science (NFFTBS) (J1103206), Research Fund for Doctoral Program of Higher Education (20110001110087) and China Postdoctoral Science Foundation (2015M580007)

  10. Wormholes from Chiral Fields

    International Nuclear Information System (INIS)

    In this paper, Lorentzian wormholes with a phantom field and chiral matter fields have been obtained. In addition, it is shown that for different values of the gravitational coupling of the chiral fields, the wormhole geometry changes. Finally, the stability of the corresponding wormholes is studied and it is shown that are unstable (eg. Ellis's wormhole instability)

  11. Spectral signatures of chirality

    DEFF Research Database (Denmark)

    Pedersen, Jesper Goor; Mortensen, Asger

    2009-01-01

    We present a new way of measuring chirality, via the spectral shift of photonic band gaps in one-dimensional structures. We derive an explicit mapping of the problem of oblique incidence of circularly polarized light on a chiral one-dimensional photonic crystal with negligible index contrast to the...

  12. Chiral Magnetic "Superfluidity"

    CERN Document Server

    Sadofyev, Andrey V

    2015-01-01

    We study a heavy impurity moving longitudinal with the direction of an external magnetic field in an anomalous chiral medium. Such system would carry a non-dissipative current of chiral magnetic effect associated with the anomaly. We show, by generalizing Landau's criterion for superfluidity, that the "anomalous component" which gives rise to the anomalous transport will {\\it not} contribute to the drag experienced by an impurity. We argue on very general basis that those systems with a strong magnetic field would exhibit the behavior of 'superfluidity" -- the motion of the heavy impurity is frictionless, in analog to the case of a superfluid. However, this "superfluidity" exists even for chiral media at finite temperature and only in the directional longitudinal with the magnetic field, in contrast to the ordinary superfluid. We will call this novel phenomenon as the Chiral Magnetic "Superfluidity". We demonstrate and confirm our general results with two complementary examples: weakly coupled chiral fermion ...

  13. Chiral Magnetic Effect and Chiral Phase Transition

    Institute of Scientific and Technical Information of China (English)

    FU Wei-Jie; LIU Yu-Xin; WU Yue-Liang

    2011-01-01

    We study the influence of the chiral phase transition on the chiral magnetic effect.The azimuthal chargeparticle correlations as functions of the temperature are calculated.It is found that there is a pronounced cusp in the correlations as the temperature reaches its critical value for the QCD phase transition.It is predicted that there will be a drastic suppression of the charge-particle correlations as the collision energy in RHIC decreases to below a critical value.We show then the azimuthal charge-particle correlations can be the signal to identify the occurrence of the QCD phase transitions in RHIC energy scan experiments.

  14. Chiral String-Soliton Model for the light chiral baryons

    CERN Document Server

    Pavlovsky, Oleg

    2010-01-01

    The Chiral String-Soliton Model is a joining of the two notions about the light chiral baryons: the chiral soliton models (like the Skyrme model) and the Quark-Gluon String models. The ChSS model is based on the Effective Chiral Lagrangian which was proposed in [arXiv:hep-ph/0306216]. We have studied the physical properties of the light chiral baryon within the framework of this ChSS model.

  15. Applications of chiral symmetry

    International Nuclear Information System (INIS)

    The author discusses several topics in the applications of chiral symmetry at nonzero temperature. First, where does the rho go? The answer: up. The restoration of chiral symmetry at a temperature Tχ implies that the ρ and a1 vector mesons are degenerate in mass. In a gauged linear sigma model the ρ mass increases with temperature, mρ(Tχ) > mρ(0). The author conjectures that at Tχ the thermal ρ - a1, peak is relatively high, at about ∼1 GeV, with a width approximately that at zero temperature (up to standard kinematic factors). The ω meson also increases in mass, nearly degenerate with the ρ, but its width grows dramatically with temperature, increasing to at least ∼100 MeV by Tχ. The author also stresses how utterly remarkable the principle of vector meson dominance is, when viewed from the modern perspective of the renormalization group. Secondly, he discusses the possible appearance of disoriented chiral condensates from open-quotes quenchedclose quotes heavy ion collisions. It appears difficult to obtain large domains of disoriented chiral condensates in the standard two flavor model. This leads to the last topic, which is the phase diagram for QCD with three flavors, and its proximity to the chiral critical point. QCD may be very near this chiral critical point, and one might thereby generated large domains of disoriented chiral condensates

  16. Chiral supergravity and anomalies

    CERN Document Server

    Mielke, E W; Macias, Alfredo; Mielke, Eckehard W.

    1999-01-01

    Similarily as in the Ashtekar approach, the translational Chern-Simons term is, as a generating function, instrumental for a chiral reformulation of simple (N=1) supergravity. After applying the algebraic Cartan relation between spin and torsion, the resulting canonical transformation induces not only decomposition of the gravitational fields into selfdual and antiselfdual modes, but also a splitting of the Rarita-Schwinger fields into their chiral parts in a natural way. In some detail, we also analyze the consequences for axial and chiral anomalies.

  17. Synthesis of Chiral Cyclopentenones.

    Science.gov (United States)

    Simeonov, Svilen P; Nunes, João P M; Guerra, Krassimira; Kurteva, Vanya B; Afonso, Carlos A M

    2016-05-25

    The cyclopentenone unit is a very powerful synthon for the synthesis of a variety of bioactive target molecules. This is due to the broad diversity of chemical modifications available for the enone structural motif. In particular, chiral cyclopentenones are important precursors in the asymmetric synthesis of target chiral molecules. This Review provides an overview of reported methods for enantioselective and asymmetric syntheses of cyclopentenones, including chemical and enzymatic resolution, asymmetric synthesis via Pauson-Khand reaction, Nazarov cyclization and organocatalyzed reactions, asymmetric functionalization of the existing cyclopentenone unit, and functionalization of chiral building blocks. PMID:27101336

  18. Catalysis of Dynamical Chiral Symmetry Breaking by Chiral Chemical Potential

    CERN Document Server

    Braguta, V V

    2016-01-01

    In this paper we study the properties of media with chiral imbalance parameterized by chiral chemical potential. It is shown that depending on the strength of interaction between constituents in the media the chiral chemical potential either creates or enhances dynamical chiral symmetry breaking. Thus the chiral chemical potential plays a role of the catalyst of dynamical chiral symmetry breaking. Physically this effect results from the appearance of the Fermi surface and additional fermion states on this surface which take part in dynamical chiral symmetry breaking. An interesting conclusion which can be drawn is that at sufficiently small temperature chiral plasma is unstable with respect to condensation of Cooper pairs and dynamical chiral symmetry breaking even for vanishingly small interactions between constituents.

  19. The quest for chirality

    Energy Technology Data Exchange (ETDEWEB)

    Bonner, W.A. [Department of Chemistry Stanford University, Stanford, California 94305 (United States)

    1996-07-01

    The indispensable role played by homochirality and chiral homogeneity in the self-replication of crucial biomolecules is stressed, with the conclusion that life could neither exist nor originate without these chiral molecular attributes. Hypotheses historically proposed for the origin of chiral molecules on Earth are reviewed, including biogenic theories as well as abiotic theories embracing both indeterminate and determinate mechanisms. Indeterminate mechanisms, including autocatalytic symmetry breaking, asymmetric adsorption on quartz and clay minerals, and asymmetric syntheses in chiral crystals, are discussed and evaluated in the context of the prebiotic environment. Abiotic determinate mechanisms based on electric, magnetic and gravitational fields, on circularly polarized light (CPL), and on parity violation effects are summarized, with the emphasis that only CPL has proved practicable experimentally, but that it would be implausible on the primitive Earth. Mechanisms for the amplification of small, indigenous enantiomeric excesses are discussed, with one involving the partial polymerization of amino acids and the partial hydrolysis of polypeptides suggested as potentially viable prebiotically. Aspects of the turbulent, chirality-destructive primeval environment are described, with the conclusion that all of the above mechanisms for the {ital terrestrial} prebiotic origin of chirality would be non-viable, and that an alternative extraterrestrial source for the accumulation of chiral molecules on primitive Earth must have been operative. A scenario for this is outlined, in which we postulate that asymmetric photolysis of the organic mantles on interstellar grains in molecular clouds by circularly polarized ultraviolet synchrotron radiation from the neutron star remnants of supernovae produces chiral molecules in the grain mantles. (Abstract Truncated)

  20. Chiral separation in microflows

    OpenAIRE

    Kostur, Marcin; Schindler, Michael; Talkner, Peter; Hänggi, Peter

    2005-01-01

    Molecules that only differ by their chirality, so called enantiomers, often possess different properties with respect to their biological function. Therefore, the separation of enantiomers presents a prominent challenge in molecular biology and belongs to the ``Holy Grail'' of organic chemistry. We suggest a new separation technique for chiral molecules that is based on the transport properties in a microfluidic flow with spatially variable vorticity. Because of their size the thermal fluctua...

  1. Chiral Odd GPDs

    Directory of Open Access Journals (Sweden)

    Goldstein Gary R.

    2015-01-01

    Full Text Available Nucleon spin structure, transversity and the tensor charge are of central importance to understanding the role of QCD in hadronic physics. A new approach to measuring orbital angular momenta of quarks in the proton via twist 3 GPDs is shown. The “flexible parametrization” of chiral even GPDs is reviewed and its transformation into the chiral odd sector is discussed. The resulting parametrization is applied to recent data on π0 and η electroproduction.

  2. Dirac brackets for the chiral Schwinger model with chiral constraint

    International Nuclear Information System (INIS)

    Dirac brackets for the chiral Schwinger model with chiral constraint are derived perturbatively from the correlation function by the BJL limit method. The results show that the Poissons brackets are not consistent in this theory. (author)

  3. Dynamic Chirality in Nuclei

    International Nuclear Information System (INIS)

    Chirality has recently been proposed as a novel feature of rotating nuclei [1]. Because the chiral symmetry is dichotomic, its spontaneous breaking by the axial angular momentum vector leads to doublets of closely lying rotational bands of the same parity. To investigate nuclear chirality, next to establish the existence of almost degenerate rotational bands, it is necessary to measure also other observables and compare them to the model predictions. The crucial test for the suggested nuclei as candidates to express chirality is based on precise lifetime measurements. Two lifetime experiments and theoretical approaches for the description of the experimental results will be presented. Lifetimes of exited states in 134Pr were measured [2,3] by means of the recoil distance Doppler-shift and Doppler-shift attenuation techniques. The branching ratios and the electric or magnetic character of the transitions were also investigated [3]. The experiments were performed at IReS, Strasbourg, using the EUROBALL IV spectrometer, in conjunction with the inner bismuth germanate ball and the Cologne coincidence plunger apparatus. Exited states in 134Pr were populated in the fusion-evaporation reaction 119Sn(19F, 4n)134Pr. The possible chiral interpretation of twin bands was investigated in the two-quasiparticle triaxial rotor [1] and interacting boson-fermion-fermion models [4]. Both theoretical approaches can describe the level-scheme of 134Pr. The analysis of the wave functions has shown that the possibility for the angular momenta of the proton, neutron, and core to find themselves in the favorable, almost orthogonal geometry, is present but is far from being dominant [3,5]. The structure is characterized by large β and γ fluctuations. The existence of doublets of bands in 134Pr can be attributed to weak chirality dominated by shape fluctuations. In a second experiment branching ratios and lifetimes in 136Pm were measured by means of the recoil distance Doppler-shift and

  4. Chiral anomalies and differential geometry

    Energy Technology Data Exchange (ETDEWEB)

    Zumino, B.

    1983-10-01

    Some properties of chiral anomalies are described from a geometric point of view. Topics include chiral anomalies and differential forms, transformation properties of the anomalies, identification and use of the anomalies, and normalization of the anomalies. 22 references. (WHK)

  5. Quarkyonic Chiral Spirals

    CERN Document Server

    Kojo, Toru; McLerran, Larry; Pisarski, Robert D

    2009-01-01

    We consider the formation of chiral density waves in Quarkyonic matter, which is a phase where cold, dense quarks experience confining forces. We model confinement following Gribov and Zwanziger, taking the gluon propagator, in Coulomb gauge and momentum space, as 1/(p^2)^2. We assume that the number of colors, N, is large, and that the quark chemical potential, mu, is much larger than renormalization mass scale, Lambda_QCD. To leading order in 1/N and Lambda_QCD, a gauge theory with Nf flavors of massless quarks in 3+1 dimensions naturally reduces to a gauge theory in 1+1 dimensions, with an enlarged flavor symmetry of SU(2Nf). Through an anomalous chiral rotation, in two dimensions a Fermi sea of massless quarks maps directly onto the corresponding theory in vacuum. A chiral condensate forms locally, and varies with the spatial position, z, as . Following Schon and Thies, we term this two dimensional pion condensate a (Quarkyonic) chiral spiral. Massive quarks also exhibit chiral spirals, with the magnitude...

  6. Chiral Quirkonium Decays

    CERN Document Server

    Fok, R

    2011-01-01

    We calculate the two-body decay rates of "quirkonium" states formed from quirks that acquire mass solely through electroweak symmetry breaking. We consider SU(N)_ic infracolor with two flavors of quirks transforming under the electroweak group (but not QCD) of the Standard Model. In one case, the quirks are in a chiral representation of the electroweak group, while in the other case, a vector-like representation. The differences in the dominant decay channels between "chiral quirkonia" versus "vector-like quirkonia" are striking. Several chiral quirkonia states can decay into the unique two-body resonance channels WH, ZH, t\\bar{t}, t\\bar{b} / b\\bar{t}, and gamma+H, which never dominate for vector-like quirkonia. Additionally, the channels WW, WZ, ZZ, and W+gamma, are shared among both chiral and vector-like quirkonia. Resonances of dileptons or light quarks (dijets) can dominate for some vector-like quirkonia states throughout their mass range, while these modes never dominate for chiral quirkonia unless the ...

  7. Chiral quirkonium decays

    International Nuclear Information System (INIS)

    We calculate the two-body decay rates of quirkonium states formed from quirks that acquire mass solely through electroweak symmetry breaking. We consider SU(N)ic infracolor with two flavors of quirks transforming under the electroweak group (but not QCD) of the standard model. In one case, the quirks are in a chiral representation of the electroweak group, while in the other case, a vectorlike representation. The differences in the dominant decay channels between 'chiral quirkonia' versus 'vectorlike quirkonia' are striking. Several chiral quirkonia states can decay into the unique two-body resonance channels WH, ZH, tt, tb/bt, and γH, which never dominate for vectorlike quirkonia. Additionally, the channels WW, WZ, ZZ, and Wγ, are shared among both chiral and vectorlike quirkonia. Resonances of dileptons or light quarks (dijets) can dominate for some vectorlike quirkonia states throughout their mass range, while these modes never dominate for chiral quirkonia unless the decays into pairs of gauge or Higgs bosons are kinematically forbidden.

  8. Chiral Invariance of Massive Fermions

    OpenAIRE

    Das, A.(University of Arizona, Tucson, AZ, 85721, USA); Hott, M

    1994-01-01

    We show that a massive fermion theory, while not invariant under the conventional chiral transformation, is invariant under a $m$-deformed chiral transformation. These transformations and the associated conserved charges are nonlocal but reduce to the usual transformations and charges when $m=0$. The $m$-deformed charges commute with helicity and satisfy the conventional chiral algebra.

  9. Chiral Synthons in Pesticide Syntheses

    NARCIS (Netherlands)

    Feringa, Bernard

    1988-01-01

    The use of chiral synthons in the preparation of enantiomerically pure pesticides is described in this chapter. Several routes to chiral synthons based on asymmetric synthesis or on natural products are illustrated. Important sources of chiral building blocks are reviewed. Furthermore the implicatio

  10. Chiral Electroweak Currents in Nuclei

    CERN Document Server

    Riska, D O

    2016-01-01

    The development of the chiral dynamics based description of nuclear electroweak currents is reviewed. Gerald E. (Gerry) Brown's role in basing theoretical nuclear physics on chiral Lagrangians is emphasized. Illustrative examples of the successful description of electroweak observables of light nuclei obtained from chiral effective field theory are presented.

  11. Holographic Chiral Magnetic Spiral

    International Nuclear Information System (INIS)

    We study the ground state of baryonic/axial matter at zero temperature chiral-symmetry broken phase under a large magnetic field, in the framework of holographic QCD by Sakai-Sugimoto. Our study is motivated by a recent proposal of chiral magnetic spiral phase that has been argued to be favored against previously studied phase of homogeneous distribution of axial/baryonic currents in terms of meson super-currents dictated by triangle anomalies in QCD. Our results provide an existence proof of chiral magnetic spiral in strong coupling regime via holography, at least for large axial chemical potentials, whereas we don't find the phenomenon in the case of purely baryonic chemical potential. (author)

  12. Chiral Quantum Optics

    CERN Document Server

    Lodahl, Peter; Stobbe, Søren; Schneeweiss, Philipp; Volz, Jürgen; Rauschenbeutel, Arno; Pichler, Hannes; Zoller, Peter

    2016-01-01

    At the most fundamental level, the interaction between light and matter is manifested by the emission and absorption of single photons by single quantum emitters. Controlling light--matter interaction is the basis for diverse applications ranging from light technology to quantum--information processing. Many of these applications are nowadays based on photonic nanostructures strongly benefitting from their scalability and integrability. The confinement of light in such nanostructures imposes an inherent link between the local polarization and propagation direction of light. This leads to {\\em chiral light--matter interaction}, i.e., the emission and absorption of photons depend on the propagation direction and local polarization of light as well as the polarization of the emitter transition. The burgeoning research field of {\\em chiral quantum optics} offers fundamentally new functionalities and applications both for single emitters and ensembles thereof. For instance, a chiral light--matter interface enables...

  13. Baryon chiral perturbation theory

    International Nuclear Information System (INIS)

    We provide a short introduction to the one-nucleon sector of chiral perturbation theory and address the issue of power counting and renormalization. We discuss the infrared regularization and the extended on-mass-shell scheme. Both allow for the inclusion of further degrees of freedom beyond pions and nucleons and the application to higher-loop calculations. As applications we consider the chiral expansion of the nucleon mass to order O(q6) and the inclusion of vector and axial-vector mesons in the calculation of nucleon form factors. Finally, we address the complex-mass scheme for describing unstable particles in effective field theory.

  14. Baryon chiral perturbation theory

    CERN Document Server

    Scherer, Stefan

    2011-01-01

    We provide a short introduction to the one-nucleon sector of chiral perturbation theory and address the issue of power counting and renormalization. We discuss the infrared regularization and the extended on-mass-shell scheme. Both allow for the inclusion of further degrees of freedom beyond pions and nucleons and the application to higher-loop calculations. As applications we consider the chiral expansion of the nucleon mass to order ${\\cal O}(q^6)$ and the inclusion of vector and axial-vector mesons in the calculation of nucleon form factors. Finally, we address the complex-mass scheme for describing unstable particles in effective field theory.

  15. Chiral quark model

    Indian Academy of Sciences (India)

    H Weigel

    2003-11-01

    In this talk I review studies of hadron properties in bosonized chiral quark models for the quark flavor dynamics. Mesons are constructed from Bethe–Salpeter equations and baryons emerge as chiral solitons. Such models require regularization and I show that the two-fold Pauli–Villars regularization scheme not only fully regularizes the effective action but also leads the scaling laws for structure functions. For the nucleon structure functions the present approach serves to determine the regularization prescription for structure functions whose leading moments are not given by matrix elements of local operators. Some numerical results are presented for the spin structure functions.

  16. Baryon chiral perturbation theory

    Science.gov (United States)

    Scherer, S.

    2012-03-01

    We provide a short introduction to the one-nucleon sector of chiral perturbation theory and address the issue of power counting and renormalization. We discuss the infrared regularization and the extended on-mass-shell scheme. Both allow for the inclusion of further degrees of freedom beyond pions and nucleons and the application to higher-loop calculations. As applications we consider the chiral expansion of the nucleon mass to order Script O(q6) and the inclusion of vector and axial-vector mesons in the calculation of nucleon form factors. Finally, we address the complex-mass scheme for describing unstable particles in effective field theory.

  17. Chiral perturbation theory

    International Nuclear Information System (INIS)

    After a general introduction to the structure of effective field theories, the main ingredients of chiral perturbation theory are reviewed. Applications include the light quark mass ratios and pion-pion scattering to two-loop accuracy. In the pion-nucleon system, the linear σ model is contrasted with chiral perturbation theory. The heavy-nucleon expansion is used to construct the effective pion-nucleon Lagrangian to third order in the low-energy expansion, with applications to nucleon Compton scattering. (author)

  18. Chiral Heat Wave and wave mixing in chiral media

    CERN Document Server

    Chernodub, M N

    2016-01-01

    We show that a hot rotating fluid of relativistic chiral fermions possesses a new gapless collective excitation associated with coherent propagation of energy density and chiral density waves along the axis of rotation. This excitation, which we call the Chiral Heat Wave, emerges due to a mixed gauge-gravitational anomaly. At finite density the Chiral Heat Wave couples to the Chiral Vortical Wave while in the presence of an external magnetic field it mixes with the Chiral Magnetic Wave. We find that the coupled waves - which are coherent fluctuations of the vector, axial and energy currents - have generally different velocities compared to the velocities of the individual waves. We also demonstrate that rotating chiral systems subjected to external magnetic field possess non-propagating metastable thermal excitations, the Dense Hot Spots.

  19. Chiral forces and molecular dissymmetry

    International Nuclear Information System (INIS)

    Chiral molecules leading to helical macromolecules seem to preserve information and extend it better. In the biological world RNA is the very paradigm for self-replication, elongation and autocatalytic editing. The nucleic acid itself is not chiral. It acquires its chirality by association with D-sugars. Although the chiral information or selectivity put in by the unit monomer is no longer of much interest to the biologists - they tend to leave it to the Darwinian selection principle to take care of it as illustrated by Frank's model - it is vital to understand the origin of chirality. There are three different approaches for the chiral origin of life: (1) Phenomenological, (2) Electromagnetic molecular and Coriolis forces and (3) Atomic or nuclear force, the neutral weak current. The phenomenological approach involves spontaneous symmetry breaking fluctuations in far for equilibrium systems or nucleation and crystallization. Chance plays a major role in the chiral molecule selected

  20. Interweaving Chiral Spirals

    CERN Document Server

    Kojo, Toru; Fukushima, Kenji; McLerran, Larry; Pisarski, Robert D

    2011-01-01

    We elaborate how to construct the interweaving chiral spirals in (2+1) dimensions, that is defined as a superposition of differently oriented chiral spirals. We divide the two-dimensional Fermi sea into distinct wedges characterized by the opening angle 2 Theta and the depth Q \\simeq pF, where pF is the Fermi momentum. Each wedge earns an energy gain by forming a single chiral spiral. The optimal values for Theta and Q are chosen by the balance between this energy gain and the energy costs from the deformed Fermi surface (dominant at large Theta) and patch-patch interactions (dominant at small Theta). We estimate these energy gains and costs by means of the expansions in terms of 1/Nc, Lambda_QCD/Q, and Theta using a non-local four-Fermi interaction model: At small 1/Nc the mass gap (chiral condensate) is large enough and the interaction among quarks and the condensate is local in momentum space thanks to the form factor in our non-local model. The fact that patch-patch interactions lie only near the patch bo...

  1. Chiral Biomarkers in Meteorites

    Science.gov (United States)

    Hoover, Richard B.

    2010-01-01

    The chirality of organic molecules with the asymmetric location of group radicals was discovered in 1848 by Louis Pasteur during his investigations of the rotation of the plane of polarization of light by crystals of sodium ammonium paratartrate. It is well established that the amino acids in proteins are exclusively Levorotary (L-aminos) and the sugars in DNA and RNA are Dextrorotary (D-sugars). This phenomenon of homochirality of biological polymers is a fundamental property of all life known on Earth. Furthermore, abiotic production mechanisms typically yield recemic mixtures (i.e. equal amounts of the two enantiomers). When amino acids were first detected in carbonaceous meteorites, it was concluded that they were racemates. This conclusion was taken as evidence that they were extraterrestrial and produced by abiologically. Subsequent studies by numerous researchers have revealed that many of the amino acids in carbonaceous meteorites exhibit a significant L-excess. The observed chirality is much greater than that produced by any currently known abiotic processes (e.g. Linearly polarized light from neutron stars; Circularly polarized ultraviolet light from faint stars; optically active quartz powders; inclusion polymerization in clay minerals; Vester-Ulbricht hypothesis of parity violations, etc.). This paper compares the measured chirality detected in the amino acids of carbonaceous meteorites with the effect of these diverse abiotic processes. IT is concluded that the levels observed are inconsistent with post-arrival biological contamination or with any of the currently known abiotic production mechanisms. However, they are consistent with ancient biological processes on the meteorite parent body. This paper will consider these chiral biomarkers in view of the detection of possible microfossils found in the Orgueil and Murchison carbonaceous meteorites. Energy dispersive x-ray spectroscopy (EDS) data obtained on these morphological biomarkers will be

  2. A Chiral Granular Gas

    Science.gov (United States)

    Tsai, J.-C.; Ye, Fangfu; Rodriguez, Juan; Gollub, J. P.; Lubensky, T. C.

    2005-05-01

    Inspired by rattleback toys, we created small chiral wires that rotate in a preferred direction on a vertically oscillating platform and quantified their motion with experiment and simulation. We demonstrate experimentally that angular momentum of rotation about particle centers of mass is converted to collective angular momentum of center-of-mass motion in a granular gas of these wires, and we introduce a continuum model that explains our observations.

  3. Chiral Crystal Growth under Grinding

    OpenAIRE

    Saito, Yukio; Hyuga, Hiroyuki

    2008-01-01

    To study the establishment of homochirality observed in the crystal growth experiment of chiral molecules from a solution under grinding, we extend the lattice gas model of crystal growth as follows. A lattice site can be occupied by a chiral molecule in R or S form, or can be empty. Molecules form homoclusters by nearest neighbor bonds. They change their chirality if they are isolated monomers in the solution. Grinding is incorporated by cutting and shafling the system randomly. It is shown ...

  4. Chiral squaring and KLT relations

    OpenAIRE

    Schreiber, Anders

    2016-01-01

    We demonstrate that amplitudes based on matter supermultiplets can be combined to provide amplitudes of vector supermultiplets by means of KLT relations. In practice we do this by developing a procedure for removing supersymmetry supercharges from super Yang-Mills theory and supergravity supermultiplets, reducing them to vector and chiral supermultiplets respectively. This way, we reduce the super KLT relations to chiral KLT relations making chiral squaring of amplitudes manifest. We study th...

  5. Chiral dynamics and baryon resonances

    OpenAIRE

    Hyodo, Tetsuo

    2010-01-01

    The structure of baryon resonance in coupled-channel meson-baryon scattering is studied from the viewpoint of chiral dynamics. The meson-baryon scattering amplitude can be successfully described together with the properties of the resonance in the scattering, by implementing the unitarity condition for the amplitude whose low energy structure is constrained by chiral theorem. Recently, there have been a major progress in the study of the structure of the resonance in chiral dynamics. We revie...

  6. Chiral nuclear thermodynamics

    CERN Document Server

    Fiorilla, Salvatore; Weise, Wolfram

    2011-01-01

    We calculate the equation of state of nuclear matter for arbitrary isospin-asymmetry up to three loop order in the free energy density in the framework of in-medium chiral perturbation theory. In our approach 1\\pi- and 2\\pi-exchange dynamics with the inclusion of the \\Delta-isobar excitation as an explicit degree of freedom, corresponding to the long- and intermediate-range correlations, are treated explicitly. Few contact terms fixed to reproduce selected known properties of nuclear matter encode the short-distance physics. Two-body as well as three-body forces are systematically included. We find a critical temperature of about 15 MeV for symmetric nuclear matter. We investigate the dependence of the liquid-gas first-order phase transition on isospin-asymmetry. In the same chiral framework we calculate the chiral condensate of isospin-symmetric nuclear matter at finite temperatures. The contribution of the \\Delta-isobar excitation is essential for stabilizing the condensate. As a result, we find no indicati...

  7. Generalized simplicial chiral models

    CERN Document Server

    Alimohammadi, M

    2000-01-01

    Using the auxiliary field representation of the simplicial chiral models on a (d-1)-dimensional simplex, we generalize the simplicial chiral models by replacing the term Tr$(AA^{\\d})$ in the Lagrangian of these models, by an arbitrary class function of $AA^{\\d}; V(AA^{\\d})$. This is the same method that has been used in defining the generalized two-dimensional Yang-Mills theories (gYM_2) from ordinary YM_2. We call these models, the " generalized simplicial chiral models ". With the help of the results of one-link integral over a U(N) matrix, we compute the large-N saddle-point equations for eigenvalue density function $\\ro (z)$ in the weak ($\\b >\\b_c$) and strong ($\\b <\\b_c$) regions. In d=2, where the model somehow relates to gYM_2 theory, we solve the saddle-point equations and find $\\ro (z)$ in two region, and calculate the explicit value of critical point $\\b_c$ for $V(B)=TrB^n (B=AA^{\\d})$. For $V(B)=Tr B^2,Tr B^3$ and Tr$B^4$, we study the critical behaviour of the model at d=2, and by calculating t...

  8. Generalized simplicial chiral models

    International Nuclear Information System (INIS)

    Using the auxiliary field representation of the simplicial chiral models on a (d-1)-dimensional simplex, the simplicial chiral models are generalized through replacing the term Tr(AA†) in the Lagrangian of these models by an arbitrary class function of AA†; V(AA†). This is the same method used in defining the generalized two-dimensional Yang-Mills theories (gYM2) from ordinary YM2. We call these models the 'generalized simplicial chiral models'. Using the results of the one-link integral over a U(N) matrix, the large-N saddle-point equations for eigenvalue density function ρ(z) in the weak (β>βc) and strong (βc) regions are computed. In d=2, where the model is in some sense related to the gYM2 theory, the saddle-point equations are solved for ρ(z) in the two regions, and the explicit value of critical point βc is calculated for V(B)=Tr Bn (B=AA†). For V(B)=Tr B2,Tr B3, and TrB4, the critical behaviour of the model at d=2 is studied, and by calculating the internal energy, it is shown that these models have a third order phase transition

  9. Chirality and protein folding

    Energy Technology Data Exchange (ETDEWEB)

    Kwiecinska, Joanna I; Cieplak, Marek [Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, 02-668 Warsaw (Poland)

    2005-05-11

    There are several simple criteria of folding to a native state in model proteins. One of them involves crossing of a threshold value of the root mean square deviation distance away from the native state. Another checks whether all native contacts are established, i.e. whether the interacting amino acids come closer than some characteristic distance. We use Go-like models of proteins and show that such simple criteria may prompt one to declare folding even though fragments of the resulting conformations have a wrong sense of chirality. We propose that a better condition of folding should augment the simple criteria with the requirement that most of the local values of the chirality should be nearly native. The kinetic discrepancy between the simple and compound criteria can be substantially reduced in the Go-like models by providing the Hamiltonian with a term which favours native values of the local chirality. We study the effects of this term as a function of its amplitude and compare it to other models such as ones with side groups and ones with angle-dependent potentials.

  10. Chirality and protein folding

    Science.gov (United States)

    Kwiecinska, Joanna I.; Cieplak, Marek

    2005-05-01

    There are several simple criteria of folding to a native state in model proteins. One of them involves crossing of a threshold value of the root mean square deviation distance away from the native state. Another checks whether all native contacts are established, i.e. whether the interacting amino acids come closer than some characteristic distance. We use Go-like models of proteins and show that such simple criteria may prompt one to declare folding even though fragments of the resulting conformations have a wrong sense of chirality. We propose that a better condition of folding should augment the simple criteria with the requirement that most of the local values of the chirality should be nearly native. The kinetic discrepancy between the simple and compound criteria can be substantially reduced in the Go-like models by providing the Hamiltonian with a term which favours native values of the local chirality. We study the effects of this term as a function of its amplitude and compare it to other models such as ones with side groups and ones with angle-dependent potentials.

  11. Chiral squaring and KLT relations

    CERN Document Server

    Schreiber, Anders

    2016-01-01

    We demonstrate that amplitudes based on matter supermultiplets can be combined to provide amplitudes of vector supermultiplets by means of KLT relations. In practice we do this by developing a procedure for removing supersymmetry supercharges from super Yang-Mills theory and supergravity supermultiplets, reducing them to vector and chiral supermultiplets respectively. This way, we reduce the super KLT relations to chiral KLT relations making chiral squaring of amplitudes manifest. We study these chiral KLT relations, discussing permutation symmetry and vanishing relations. Finally some explicit calculations are done to show how the relations work in detail.

  12. The chiral magnetic effect in hydrodynamical approach

    OpenAIRE

    Sadofyev, A. V.; Isachenkov, M. V.

    2010-01-01

    In quark-gluon plasma nonzero chirality can be induced by the chiral anomaly. When a magnetic field is applied to a system with nonzero chirality an electromagnetic current is induced along the magnetic field. This phenomenon is called the chiral magnetic effect. In this paper appearance of the chiral magnetic effect in hydrodynamical approximation is shown. We consider a hydrodynamical model for chiral liquid with two independent currents of left and right handed particles in the presence of...

  13. CHIRAL SYMMETRIES IN NUCLEAR PHYSICS

    International Nuclear Information System (INIS)

    The theoretical concepts of a chirally symmetric meson field theory are reviewed and an overview of the most relevant applications in nuclear physics is given. This includes a unified description of the vacuum properties of hadrons, finite nuclei and hot, dense and strange nuclear matter in an extended chiral SU(3)L/SU(3)R σ-ω model

  14. Two-chiral component microemulsion EKC - chiral surfactant and chiral oil. Part 2: diethyl tartrate.

    Science.gov (United States)

    Kahle, Kimberly A; Foley, Joe P

    2007-08-01

    In this second study on dual-chirality microemulsions containing a chiral surfactant and a chiral oil, a less hydrophobic and lower interfacial tension chiral oil, diethyl tartrate, is employed (Part 1, Foley, J. P. et al.., Electrophoresis, DOI: 10.1002/elps.200600551). Six stereochemical combinations of dodecoxycarbonylvaline (DDCV: R, S, or racemic, 2.00% w/v), racemic 2-hexanol (1.65% v/v), and diethyl tartrate (D, L, or racemic, 0.88% v/v) were examined as pseudostationary phases (PSPs) for the enantioseparation of six chiral pharmaceutical compounds: pseudoephedrine, ephedrine, N-methyl ephedrine, metoprolol, synephrine, and atenolol. Average efficiencies increased with the addition of a chiral oil to R-DDCV PSP formulations. Modest improvements in resolution and enantioselectivity (alpha(enant)) were achieved with two-chiral-component systems over the one-chiral-component microemulsion. Slight enantioselective synergies were confirmed using a thermodynamic model. Results obtained in this study are compared to those obtained in Part 1 as well as those obtained with chiral MEEKC using an achiral, low-interfacial-tension oil (ethyl acetate). Dual-chirality microemulsions with the more hydrophobic oil dibutyl tartrate yielded, relative to diethyl tartrate, higher efficiencies (100,000-134,000 vs. 80,800-94,300), but lower resolution (1.64-1.91 vs. 2.08-2.21) due to lower enantioselectivities (1.060-1.067 vs. 1.078-1.081). Atenolol enantiomers could not be separated with the dibutyl tartrate-based microemulsions but were partially resolved using diethyl tartrate microemulsions. A comparable single-chirality microemulsion based on the achiral oil ethyl acetate yielded, relative to diethyl tartrate, lower efficiency (78 300 vs. 91 600), higher resolution (1.99 vs. 1.83), and similar enantioselectivities. PMID:17597467

  15. Mass-Selective Chiral Analysis.

    Science.gov (United States)

    Boesl, Ulrich; Kartouzian, Aras

    2016-06-12

    Three ways of realizing mass-selective chiral analysis are reviewed. The first is based on the formation of diastereomers that are of homo- and hetero- type with respect to the enantiomers of involved chiral molecules. This way is quite well-established with numerous applications. The other two ways are more recent developments, both based on circular dichroism (CD). In one, conventional or nonlinear electronic CD is linked to mass spectrometry (MS) by resonance-enhanced multiphoton ionization. The other is based on CD in the angular distribution of photoelectrons, which is measured in combination with MS via photoion photoelectron coincidence. Among the many important applications of mass-selective chiral analysis, this review focuses on its use as an analytical tool for the development of heterogeneous enantioselective chemical catalysis. There exist other approaches to combine chiral analysis and mass-selective detection, such as chiral chromatography MS, which are not discussed here. PMID:27070181

  16. Mass-Selective Chiral Analysis

    Science.gov (United States)

    Boesl, Ulrich; Kartouzian, Aras

    2016-06-01

    Three ways of realizing mass-selective chiral analysis are reviewed. The first is based on the formation of diastereomers that are of homo- and hetero- type with respect to the enantiomers of involved chiral molecules. This way is quite well-established with numerous applications. The other two ways are more recent developments, both based on circular dichroism (CD). In one, conventional or nonlinear electronic CD is linked to mass spectrometry (MS) by resonance-enhanced multiphoton ionization. The other is based on CD in the angular distribution of photoelectrons, which is measured in combination with MS via photoion photoelectron coincidence. Among the many important applications of mass-selective chiral analysis, this review focuses on its use as an analytical tool for the development of heterogeneous enantioselective chemical catalysis. There exist other approaches to combine chiral analysis and mass-selective detection, such as chiral chromatography MS, which are not discussed here.

  17. Chiral Nuclear Dynamics II

    CERN Document Server

    Rho, Mannque

    2008-01-01

    This is the sequel to the first volume to treat in one effective field theory framework the physics of strongly interacting matter under extreme conditions. This is vital for understanding the high temperature phenomena taking place in relativistic heavy ion collisions and in the early Universe, as well as the high-density matter predicted to be present in compact stars. The underlying thesis is that what governs hadronic properties in a heat bath and/or a dense medium is hidden local symmetry which emerges from chiral dynamics of light quark systems and from the duality between QCD in 4D and

  18. Entwicklung neuer chiraler Metathesekatalysatoren

    OpenAIRE

    Schlesiger, David Alexander

    2012-01-01

    Diese Arbeit befasst sich im ersten Teil mit der Synthese chiraler Rutenium-Metathesekatalysatoren. Diese zeichnen sich durch eine Monosubstitution im Rückgrat des N-heterocyclischen Carben-Liganden (NHC-Liganden) aus. Der Katalysator wurde hierbei ausgehend von L-Valin hergestellt. Der Weg verlief über eine Sulfamidat-Zwischenstufe und war bezüglich Ausbeute und Flexibilität dem ursprünglichen Syntheseweg überlegen. Die hoch flexible Route über das Sulfamidat ermöglichte die Herstellung des ...

  19. On Chiral and Nonchiral 1D Supermultiplets

    CERN Document Server

    Toppan, Francesco

    2011-01-01

    In this talk I discuss and clarify some issues concerning chiral and nonchiral properties of the one-dimensional supermultiplets of the N-Extended Supersymmetry. Quaternionic chirality can be defined for N=4,5,6,7,8. Octonionic chirality for N=8 and beyond. Inequivalent chiralities only arise when considering several copies of N=4 or N=8 supermultiplets.

  20. Constructing Self-Dual Chiral Polytopes

    OpenAIRE

    Cunningham, Gabe

    2011-01-01

    An abstract polytope is chiral if its automorphism group has two orbits on the flags, such that adjacent flags belong to distinct orbits. There are still few examples of chiral polytopes, and few constructions that can create chiral polytopes with specified properties. In this paper, we show how to build self-dual chiral polytopes using the mixing construction for polytopes.

  1. Repulsive Casimir Force in Chiral Metamaterials

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, R.; Zhou, J.; Koschny, Th.; Economou, E.N.; Soukoulis, C.M.

    2009-09-04

    We demonstrate theoretically that one can obtain repulsive Casimir forces and stable nanolevitations by using chiral metamaterials. By extending the Lifshitz theory to treat chiral metamaterials, we find that a repulsive force and a minimum of the interaction energy possibly exist for strong chirality, under realistic frequency dependencies and correct limiting values (for zero and infinite frequencies) of the permittivity, permeability, and chiral coefficients.

  2. Repulsive Casimir Force in Chiral Metamaterials

    OpenAIRE

    Zhao, R.; Zhou, J.; Koschny, Th.; Economou, E. N.; Soukoulis, C. M.

    2009-01-01

    We demonstrate theoretically that one can obtain repulsive Casimir forces and stable nanolevitations by using chiral metamaterials. By extending the Lifshitz theory to treat chiral metamaterials, we find that a repulsive force and a minimum of the interaction energy exist for strong chirality, under realistic frequency dependencies and correct limiting values (for zero and infinite frequencies) of the permittivity, permeability, and chiral coefficients.

  3. Chiral limit of QCD

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, R.

    1994-12-31

    This talk contains an analysis of quenched chiral perturbation theory and its consequences. The chiral behavior of a number of quantities such as the pion mass m{sub pi}{sup 2}, the Bernard-Golterman ratios R and {sub X}, the masses of nucleons, and the kaon B-parameter are examined to see if the singular terms induced by the additional Goldstone boson, {eta}{prime}, are visible in present data. The overall conclusion (different from that presented at the lattice meeting) of this analysis is that even though there are some caveats attached to the indications of the extra terms induced by {eta}{prime} loops, the standard expressions break down when extrapolating the quenched data with m{sub q} < m{sub s}/2 to physical light quarks. I then show that due to the single and double poles in the quenched {eta}{prime}, the axial charge of the proton cannot be calculated using the Adler-Bell-Jackiw anomaly condition. I conclude with a review of the status of the calculation of light quark masses from lattice QCD.

  4. Chiral symmetry and scalars

    International Nuclear Information System (INIS)

    The suggestion by Jaffe that if σ is a light q2q-bar2 state 0++ then even the fundamental chiral transformation properties of the σ becomes unclear, has stimulated much interest. Adler pointed out that in fact the seminal work on chiral symmetry via PCAC consistency, is really quite consistent with the σ being predominantly q2q-bar2. This interpretation was actually backed by subsequent work on effective Lagrangian methods for linear and non linear realizations. More recent work of Achasov suggests that intermediate four-quark states determine amplitudes involving other scalars a0(980) and f0(980) below 1 GeV, and the report by Ning Wu that study on σ meson in J/ψ → ωπ+π- continue to support a non qq-bar σ with mass as low as 390 MeV. It is also noted that more recent re-analysis of πK scattering by S. Ishida et al. together with the work of the E791 Collaboration, support the existence of the scalar κ particle with comparatively light mass as well

  5. Chiral fiber optical isolator

    Science.gov (United States)

    Kopp, Victor I.; Zhang, Guoyin; Zhang, Sheng; Genack, Azriel Z.; Neugroschl, Dan

    2009-02-01

    We propose an in-fiber chiral optical isolator based on chiral fiber polarizer technology and calculate its performance by incorporating the magnetic field into the scattering matrix. The design will be implemented in a special preform, which is passed through a miniature heat zone as it is drawn and twisted. The birefringence of the fiber is controlled by adjusted the diameter of a dual-core optical fiber. By adjusting the twist, the fiber can convert linear to circular polarization and reject one component of circular polarization. In the novel central portion of the isolator, the fiber diameter is large. The effective birefringence of the circular central core with high Verdet constant embedded in an outer core of slightly smaller index of refraction is small. The central potion is a non-reciprocal polarization converter which passes forward traveling left circularly polarized (LCP) light as LCP, while converting backward propagating LCP to right circularly polarized (RCP) light. Both polarizations of light traveling backwards are scattered out of the isolator. Since it is an all-glass structure, we anticipate that the isolator will be able to handle several watts of power and will be environmentally robust.

  6. Chiral perturbation theory with nucleons

    International Nuclear Information System (INIS)

    I review the constraints posed on the interactions of pions, nucleons and photons by the spontaneously broken chiral symmetry of QCD. The framework to perform these calculations, chiral perturbation theory, is briefly discussed in the meson sector. The method is a simultaneous expansion of the Greens functions in powers of external moments and quark masses around the massless case, the chiral limit. To perform this expansion, use is made of a phenomenological Lagrangian which encodes the Ward-identities and pertinent symmetries of QCD. The concept of chiral power counting is introduced. The main part of the lectures of consists in describing how to include baryons (nucleons) and how the chiral structure is modified by the fact that the nucleon mass in the chiral limit does not vanish. Particular emphasis is put on working out applications to show the strengths and limitations of the methods. Some processes which are discussed are threshold photopion production, low-energy compton scattering off nucleons, πN scattering and the σ-term. The implications of the broken chiral symmetry on the nuclear forces are briefly described. An alternative approach, in which the baryons are treated as very heavy fields, is touched upon

  7. Quarks, baryons and chiral symmetry

    CERN Document Server

    Hosaka, Atsushi

    2001-01-01

    This book describes baryon models constructed from quarks, mesons and chiral symmetry. The role of chiral symmetry and of quark model structure with SU(6) spin-flavor symmetry are discussed in detail, starting from a pedagogic introduction. Emphasis is placed on symmetry aspects of the theories. As an application, the chiral bag model is studied for nucleon structure, where important methods of theoretical physics, mostly related to the semiclassical approach for a system of strong interactions, are demonstrated. The text is more practical than formal; tools and ideas are explained in detail w

  8. Front-Form Chiral Multiplets

    CERN Document Server

    Gómez-Rocha, María

    2012-01-01

    In this article we point out that the unitary transformation that relates the chiral basis $\\{R; I J^{PC}\\}$ and the $\\{I; ^{2S+1}L_J \\}$ basis, which was already derived for canonical spin in instant form, is also applicable in light-cone representations. From the most general expression for the Clebsch-Gordan coefficients of the Poincar\\'e group one can see that the chiral limit brings the angular momentum coupling into a simple form that permits a clear relation in terms of SU(2) Clebsch-Gordan coefficients. It provides a tool of measurement of chiral symmetry in relativistic composite systems.

  9. Chiral Fermions on the Lattice

    CERN Document Server

    Bietenholz, Wolfgang

    2010-01-01

    In the last century the non-perturbative regularization of chiral fermions was a long-standing problem. We review how this problem was finally overcome by the formulation of a modified but exact form of chiral symmetry on the lattice. This also provides a sound definition of the topological charge of lattice gauge configurations. We illustrate a variety of applications to QCD in the p-, the epsilon- and the delta-regime, where simulation results can now be related to Random Matrix Theory and Chiral Perturbation Theory. The latter contains Low Energy Constants as free parameters, and we comment on their evaluation from first principles of QCD.

  10. Field induced spin chirality and chirality switching in magnetic multilayers

    International Nuclear Information System (INIS)

    The physical origin of the field-induced spin chirality experimentally observed in rare earth multilayers is determined. It is shown that the effect is possible due to the interplay between solid-state exchange interactions (the Ruderman–Kittel–Kasuya–Yosida and the Dsyaloshinsky–Moriya interactions), the external magnetic field and a special confinement of magnetic constituents. The presented model describes a certain temperature dependence of the chirality factor in agreement with experimental data and opens a new way to design nanostructured objects with predicted handedness. - Highlights: • Field-induced spin chirality in magnetic multilayers is explained. • The roles of the RKKY, the DM and the Zeeman interactions are clarified. • Theoretical analysis of the chirality factor is in agreement with experimental data

  11. Chiral Relaxation Time at the Chiral Crossover of Quantum Chromodynamics

    CERN Document Server

    Ruggieri, M; Chernodub, M

    2016-01-01

    We study microscopic processes responsible for chirality flips in the thermal bath of Quantum Chromodynamics at finite temperature and zero baryon chemical potential. We focus on the temperature range where the crossover from chirally broken phase to quark-gluon plasma takes place, namely $T \\simeq (150, 200)$ MeV. The processes we consider are quark-quark scatterings mediated by collective excitations with the quantum number of pions and $\\sigma$-meson, hence we refer to these processes simply as \\sugg{to} one-pion (one-$\\sigma$) exchange\\sugg{s}. We use a Nambu-Jona-Lasinio model to compute equilibrium properties of the thermal bath, as well as the relevant scattering kernel to be used in the collision integral to estimate the chiral relaxation time $\\tau$. We find $\\tau\\simeq 0.1 \\div 1$ fm/c around the chiral crossover.

  12. Chiral allyl silane additions to chiral α-substituted aldehydes

    International Nuclear Information System (INIS)

    Chiral allyl silane 3 reacted with chiral α-methyl-β-siloxy-aldehydes to afford the corresponding 1,4-syn-products with good diastereo-selectivities independent of the absolute stereochemistry of these aldehydes. The best selectivities are observed when the reactions are carried out by trans metallation of the allyl silane 3 using Tin (IV) Chloride in CH2 CL2 at -78 deg C, before addition of the aldehydes. (author)

  13. Spectral study of a chiral limit without chiral condensate

    OpenAIRE

    Bietenholz, Wolfgang; Hip, Ivan

    2009-01-01

    Random Matrix Theory (RMT) has elaborated successful predictions for Dirac spectra in field theoretical models. However, a generic assumption by RMT has been a non-vanishing chiral condensate $\\Sigma$ in the chiral limit. Here we consider the 2-flavour Schwinger model, where this assumption does not hold. We simulated this model with dynamical overlap hypercube fermions, and entered terra incognita by analysing this Dirac spectrum. The usual RMT prediction for the unfolded level spacing distr...

  14. Chiral Induction with Chiral Conformational Switches in the Limit of Low "Sergeants to Soldiers" Ratio

    DEFF Research Database (Denmark)

    Nuermaimaiti, Ajiguli; Bombis, Christian; Knudsen, Martin Markvard;

    2014-01-01

    " mechanism for an oligo(phenylene ethynylene) based chiral conformational switch by coadsorbing it with an intrinsically chiral seed on Au(111). Through statistical analysis of scanning tunneling microscopy (STM) data we demonstrate successful chiral induction with a very low concentration of seeding...... molecules down to 3%. The microscopic mechanism for the observed chiral induction is suggested to involve nucleation of the intrinsically chiral seeds, allowing for effective transfer and amplification of chirality to large numbers of soldier target molecules....

  15. Life's chirality from prebiotic environments

    Science.gov (United States)

    Gleiser, Marcelo; Walker, Sara Imari

    2012-10-01

    A key open question in the study of life is the origin of biomolecular homochirality: almost every life-form on Earth has exclusively levorotary amino acids and dextrorotary sugars. Will the same handedness be preferred if life is found elsewhere? We review some of the pertinent literature and discuss recent results suggesting that life's homochirality resulted from sequential chiral symmetry breaking triggered by environmental events. In one scenario, autocatalytic prebiotic reactions undergo stochastic fluctuations due to environmental disturbances, in a mechanism reminiscent of evolutionary punctuated equilibrium: short-lived destructive events may lead to long-term enantiomeric excess. In another, chiral-selective polymerization reaction rates influenced by environmental effects lead to substantial chiral excess even in the absence of autocatalysis. Applying these arguments to other potentially life-bearing platforms has implications to the search for extraterrestrial life: we predict that a statistically representative sampling of extraterrestrial stereochemistry will be racemic (chirally neutral) on average.

  16. Review of chiral perturbation theory

    Indian Academy of Sciences (India)

    B Ananthanarayan

    2003-11-01

    A review of chiral perturbation theory and recent developments on the comparison of its predictions with experiment is presented. Some interesting topics with scope for further elaboration are touched upon.

  17. Chiral anomaly on a lattice

    CERN Document Server

    Mickelsson, J

    1996-01-01

    A calculation of the chiral anomaly on a finite lattice without fermion doubling is presented . The lattice gauge field is defined in the spirit of noncommutative geometry. Standard formulas for the continuum anomaly are obtained as a limit.

  18. Chiral thermodynamics of nuclear matter

    Energy Technology Data Exchange (ETDEWEB)

    Fiorilla, Salvatore

    2012-10-23

    The equation of state of nuclear matter is calculated at finite temperature in the framework of in-medium chiral perturbation theory up to three-loop order. The dependence of its thermodynamic properties on the isospin-asymmetry is investigated. The chiral quark condensate is evaluated for symmetric nuclear matter. Its behaviour as a function of density and temperature sets important nuclear physics constraints for the QCD phase diagram.

  19. Chiral thermodynamics of nuclear matter

    International Nuclear Information System (INIS)

    The equation of state of nuclear matter is calculated at finite temperature in the framework of in-medium chiral perturbation theory up to three-loop order. The dependence of its thermodynamic properties on the isospin-asymmetry is investigated. The chiral quark condensate is evaluated for symmetric nuclear matter. Its behaviour as a function of density and temperature sets important nuclear physics constraints for the QCD phase diagram.

  20. Chiral symmetry and lattice fermions

    CERN Document Server

    Creutz, Michael

    2013-01-01

    Lattice gauge theory and chiral perturbation theory are among the primary tools for understanding non-perturbative aspects of QCD. I review several subtle and sometimes controversial issues that arise when combining these techniques. Among these are one failure of partially quenched chiral perturbation theory when the valence quarks become lighter than the average sea quark mass and a potential ambiguity in comparisons of perturbative and lattice properties of non-degenerate quarks.

  1. Restoration of Chiral Symmetry in Excited Hadrons

    International Nuclear Information System (INIS)

    Physics of the low-lying and high-lying hadrons in the light flavor sector is reviewed. While the low-lying hadrons are strongly affected by the spontaneous breaking of chiral symmetry, in the high-lying hadrons the chiral symmetry is restored. A manifestation of the chiral symmetry restoration in excited hadrons is a persistence of the chiral multiplet structure in both baryon and meson spectra. Meson and baryon chiral multiplets are classified. A relation between the chiral symmetry restoration and the string picture of excited hadrons is discussed. (author)

  2. Using the Chiral Organophosphorus Derivatizing Agents for Determination of the Enantiomeric Composition of Chiral Carboxylic Acids by 31PNMR Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    Chao CHE; Zhong Ning ZHANG; Gui Lan HUANG; Xin Xing WANG; Zhao Hai QIN

    2004-01-01

    The use of chiral organophosphorus derivatizing agents prepared in situ from chiral tartrate or chiral diamine for the 31PNMR determination of the enantiomeric composition of chiral carboxylic acids is described. The method is accurate, reliable and convenient.

  3. Chiral symmetry in rotating systems

    Science.gov (United States)

    Malik, Sham S.

    2015-08-01

    The triaxial rotating system at critical angular momentum I ≥Iband exhibits two enatiomeric (the left- and right-handed) forms. These enatiomers are related to each other through dynamical chiral symmetry. The chiral symmetry in rotating system is defined by an operator χ ˆ =Rˆy (π) T ˆ, which involves the product of two distinct symmetries, namely, continuous and discrete. Therefore, new guidelines are required for testing its commutation with the system Hamiltonian. One of the primary objectives of this study is to lay down these guidelines. Further, the possible impact of chiral symmetry on the geometrical arrangement of angular momentum vectors and investigation of observables unique to nuclear chiral-twins is carried out. In our model, the angular momentum components (J1, J2, J3) occupy three mutually perpendicular axes of triaxial shape and represent a non-planar configuration. At certain threshold energy, the equation of motion in angular momentum develops a second order phase transition and as a result two distinct frames (i.e., the left- and right-handed) are formed. These left- and right-handed states correspond to a double well system and are related to each other through chiral operator. At this critical angular momentum, the centrifugal and Coriolis interactions lower the barrier in the double well system. The tunneling through the double well starts, which subsequently lifts the degeneracy among the rotational states. A detailed analysis of the behavior of rotational energies, spin-staggering, and the electromagnetic transition probabilities of the resulting twin-rotational bands is presented. The ensuing model results exhibit similarities with many observed features of the chiral-twins. An advantage of our formalism is that it is quite simple and it allows us to pinpoint the understanding of physical phenomenon which lead to chiral-twins in rotating systems.

  4. Chaos of chiral condensate

    CERN Document Server

    Hashimoto, Koji; Yoshida, Kentaroh

    2016-01-01

    Assigning a chaos index for vacua of generic quantum field theories is a challenging problem. We find chaotic behavior of chiral condensates of a quantum gauge theory at strong coupling limit, by using the AdS/CFT correspondence. We evaluate the time evolution of homogeneous quark condensates and in an N=2 supersymmetric QCD with the SU(N_c) gauge group at large N_c and at large 't Hooft coupling lambda. At an equivalent classical gravity picture, a Lyapunov exponent is readily defined. We show that the condensates exhibit chaotic behavior for energy density E > (6x10^2) (N_c/lambda^2) (m_q)^4 where m_q is the quark mass. The energy region of the chaotic vacua of the N=2 supersymmetric QCD increases for smaller N_c or larger lambda. The Lyapunov exponent is calculated as a function of the theory (N_c,lambda,E), showing that the N=2 supersymmetric QCD is more chaotic for smaller N_c.

  5. Chiral Thirring-Wess Model

    CERN Document Server

    Rahaman, Anisur

    2015-01-01

    The vector type of interaction of the Thirring-Wess model was replaced by the chiral type and a new model was presented which was termed as chiral Thirring-Wess model in \\cite{THAR}. The model was studied there with a Faddeevian class of regularization that contained few ambiguity parameters with the apprehension that unitarity might be threatened like the chiral generation of the Schwinger model. In the present work it has been shown that no counter term containing the regularization ambiguity is needed for this model to be physically sensible. So the chiral Thirring-Wess model is studied here without the presence of any ambiguity parameter and it has been found that the model not only remain exactly solvable but also does not loose the unitarity like the chiral generation of the Schwinger model. The phase space structure and the theoretical spectrum of this new model has been determined in the present scenario through Dirac's method of quantization of constraint system. The theoretical spectrum is found to ...

  6. Water-soluble chiral metallopeptoids.

    Science.gov (United States)

    Baskin, Maria; Maayan, Galia

    2015-09-01

    Metal ions play a significant role in the activity of biological systems including catalysis, recognition and folding. Therefore, introducing metal ions into peptidomimetic oligomers is a potential way for creating biomimetic metal complexes toward applications in sensing, recognition, drug design and catalysis. Herein we report the design, synthesis and characterization of water-soluble chiral N-substituted glycine oligomers, "peptoids," with one and two distinct intramolecular binding sites for metal ions such as copper and cobalt. We demonstrate for the first time the incorporation of the chiral hydrophilic group (S)-(+)-1-methoxy-2-propylamine (Nsmp) within peptoid sequences, which provides both chirality and water solubility. Two peptoids, a heptamer, and a dodecamer bearing two and four 8-hydroxyquinoline (HQ) groups respectively as metal-binding ligands, were synthesized on solid support using the submonomer approach. Using UV-titrations and ESI-MS analysis we demonstrate the creation of a novel metallopeptoid bearing two metal ions in distinct binding sites via intramolecular chelation. Exciton couplet circular dichroism (ECCD) demonstrated chiral induction from the chiral non-helical peptoids to the metal centers. PMID:25969151

  7. Chiral dynamics of baryons in the perturbative chiral quark model

    Energy Technology Data Exchange (ETDEWEB)

    Pumsa-ard, K.

    2006-07-01

    In this work we develop and apply variants of a perturbative chiral quark model (PCQM) to the study of baryonic properties dominantly in the low-energy region. In a first step we consider a noncovariant form of the PCQM, where confinement is modelled by a static, effective potential and chiral corrections are treated to second order, in line with similar chiral quark models. We apply the PCQM to the study of the electromagnetic form factors of the baryon octet. We focus in particular on the low-energy observables such as the magnetic moments, the charge and magnetic radii. In addition, the electromagnetic N-delta transition is also studied in the framework of the PCQM. In the chiral loop calculations we consider a quark propagator, which is restricted to the quark ground state, or in hadronic language to nucleon and delta intermediate states, for simplicity. We furthermore include the low-lying excited states to the quark propagator. In particular, the charge radius of the neutron and the transverse helicity amplitudes of the N-delta transition are considerably improved by this additional effect. In a next step we develop a manifestly Lorentz covariant version of the PCQM, where in addition higher order chiral corrections are included. The full chiral quark Lagrangian is motivated by and in analogy to the one of Chiral Perturbation Theory (ChPT). This Lagrangian contains a set of low energy constants (LECs), which are parameters encoding short distance effects and heavy degrees of freedom. We evaluate the chiral Lagrangian to order O(p{sup 4}) and to one loop to generate the dressing of the bare quark operators by pseudoscalar mesons. In addition we include the vector meson degrees of freedom in our study. Projection of the dressed quark operators on the baryonic level serves to calculate the relevant matrix elements. In a first application of this scheme, we resort to a parameterization of the valence quark form factors in the electromagnetic sector. Constraints

  8. Repulsive Casimir force in chiral metamaterials.

    Science.gov (United States)

    Zhao, R; Zhou, J; Koschny, Th; Economou, E N; Soukoulis, C M

    2009-09-01

    We demonstrate theoretically that one can obtain repulsive Casimir forces and stable nanolevitations by using chiral metamaterials. By extending the Lifshitz theory to treat chiral metamaterials, we find that a repulsive force and a minimum of the interaction energy possibly exist for strong chirality, under realistic frequency dependencies and correct limiting values (for zero and infinite frequencies) of the permittivity, permeability, and chiral coefficients. PMID:19792309

  9. Chiral gap effect in curved space

    CERN Document Server

    Flachi, Antonino

    2014-01-01

    We discuss a new type of QCD phenomenon induced in curved space. In the QCD vacuum a mass gap of Dirac fermions is attributed to the spontaneous breaking of chiral symmetry. If the curvature is positive large, the chiral condensate melts but a chiral invariant mass gap can still remain, which we name the chiral gap effect in curved space. This leads to decoupling of quark deconfinement which implies a view of black holes surrounded by a first-order QCD phase transition.

  10. Chiral measurements with the Fixed-Point Dirac operator and construction of chiral currents

    International Nuclear Information System (INIS)

    In this preliminary study, we examine the chiral properties of the parametrized Fixed-Point Dirac operator DFP, see how to improve its chirality via the Overlap construction, measure the renormalized quark condensate Σ-circumflex and the topological susceptibility χt, and investigate local chirality of near zero modes of the Dirac operator. We also give a general construction of chiral currents and densities for chiral lattice actions

  11. Shear Viscosity of Turbulent Chiral Plasma

    CERN Document Server

    Kumar, Avdhesh; Das, Amita; Kaw, P K

    2016-01-01

    It is well known that the difference between the chemical potentials of left-handed and right-handed particles in a parity violating (chiral) plasma can lead to an instability. We show that the chiral instability may drive turbulent transport. Further we estimate the anomalous viscosity of chiral plasma arising from the enhanced collisionality due to turbulence.

  12. Lattice QCD with dynamical chirally improved quarks

    International Nuclear Information System (INIS)

    Full text: We simulate lattice QCD with two flavors of chirally improved dynamical (sea) quarks. The chirally improved lattice action allows to address some of the questions concerning chiral symmetry in lattice QCD.We discuss the status and prospects of our simulations as well as recent results. (author)

  13. Quenched Chiral Perturbation Theory to one loop

    NARCIS (Netherlands)

    Colangelo, G.; Pallante, E.

    1998-01-01

    The divergences of the generating functional of quenched Chiral Perturbation theory (qCHPT) to one loop are computed in closed form. We show how the quenched chiral logarithms can be reabsorbed in the renormalization of the B0 parameter of the leading order Lagrangian. Finally, we do the chiral powe

  14. Neutrino Oscillation Induced by Chiral Phase Transition

    Institute of Scientific and Technical Information of China (English)

    MU Cheng-Fu; SUN Gao-Feng; ZHUANG Peng-Fei

    2009-01-01

    Electric charge neutrality provides a relationship between chiral dynamics and neutrino propagation in compact stars.Due to the sudden drop of the electron density at the first-order chiral phase transition,the oscillation for low energy neutrinos is significant and can be regarded as a signature of chiral symmetry restoration in the core of compact stars.

  15. Nonequilibrium Chiral Dynamics and Effective Lagrangians

    CERN Document Server

    Nicola, A G

    2001-01-01

    We review our recent work on Chiral Lagrangians out of thermal equilibrium, which are introduced to analyse the pion gas formed after a Relativistic Heavy Ion Collision. Chiral Perturbation Theory is extended by letting $\\fpi$ be time dependent and allows to describe explosive production of pions in parametric resonance. This mechanism could be relevant if hadronization occurs at the chiral phase transition.

  16. Solutions of ward's modified chiral model

    International Nuclear Information System (INIS)

    We discuss the adaptation of Uhlenbeck's method of solving the chiral model in 2 Euclidean dimensions to Ward's modified chiral model in (2+1) dimensions. We show that the method reduces the problem of solving the second-order partial differential equations for the chiral field to solving a sequence of first-order partial differential equations for time dependent projector valued fields

  17. Chiral interaction and biomolecular evolution

    International Nuclear Information System (INIS)

    Recent developments in the concept of chiral interaction open now new options and dynamical possibilities for biomolecules which have so far been overlooked. A few of these possibilities are mentioned, such as the control mechanism of enzymatic activity and the role played by non-ergodicity in evolutionary processes. It is shown that chiral interaction, being a surface phenomenon, does not obey Barron's symmetry constraints, which are suitable for force fields present in bulk interactions. In particular, the situation at the ocean-air surface in the prebiotic era is described, as well as the possible role played by chiral interaction in conjunction with the terrestrial magnetic field normal to the ocean surface, which could have lead to a process of deracernization at the ocean-air interface. (author)

  18. Chiral symmetry on the lattice

    International Nuclear Information System (INIS)

    The author reviews some of the difficulties associated with chiral symmetry in the context of a lattice regulator. The author discusses the structure of Wilson Fermions when the hopping parameter is in the vicinity of its critical value. Here one flavor contrasts sharply with the case of more, where a residual chiral symmetry survives anomalies. The author briefly discusses the surface mode approach, the use of mirror Fermions to cancel anomalies, and finally speculates on the problems with lattice versions of the standard model

  19. Chiral Baryon with Quantized Pions

    CERN Document Server

    McNeil, J A

    1993-01-01

    We study a hybrid chiral model for the nucleon based on the linear sigma model with explicit quarks. We solve the model using a Fock-space configuration consisting of three quarks plus three quarks and a pion as the ground state ansatz in place of the ``hedgehog'' ansatz. We minimize the expectation value of the chiral hamiltonian in this ground state configuration and solve the resulting equations for nucleon quantum numbers. We calculate the canonical set of nucleon observables and compare with previous work.

  20. Collisions in Chiral Kinetic Theory.

    Science.gov (United States)

    Chen, Jing-Yuan; Son, Dam T; Stephanov, Mikhail A

    2015-07-10

    Using a covariant formalism, we construct a chiral kinetic theory Lorentz invariant to order O(ℏ), which includes collisions. We find a new contribution to the particle number current due to the side jumps required by the conservation of angular momentum during collisions. We also find a conserved symmetric stress-energy tensor as well as the H function obeying Boltzmann's H theorem. We demonstrate their use by finding a general equilibrium solution and the values of the anomalous transport coefficients characterizing the chiral vortical effect. PMID:26207458

  1. Collisions in Chiral Kinetic Theory

    CERN Document Server

    Chen, Jing-Yuan; Stephanov, Mikhail A

    2015-01-01

    Using a covariant formalism, we construct a chiral kinetic theory Lorentz invariant to order $\\mathcal O(\\hbar)$ which includes collisions. We find a new contribution to the particle number current due to the side jumps required by the conservation of angular momentum during collisions. We also find a conserved symmetric stress-energy tensor as well as the $H$-function obeying Boltzmann's $H$-theorem. We demonstrate their use by finding a general equilibrium solution and the values of the anomalous transport coefficients characterizing chiral vortical effect.

  2. Holographic Chiral Electric Separation Effect

    OpenAIRE

    Pu, Shi; Wu, Shang-Yu; Yang, Di-Lun

    2014-01-01

    We investigate the chiral electric separation effect, where an axial current is induced by an electric field in the presence of both vector and axial chemical potentials, in a strongly coupled plasma via the Sakai-Sugimoto model with an $U(1)_R\\times U(1)_L$ symmetry. By introducing different chemical potentials in $U(1)_R$ and $U(1)_L$ sectors, we compute the axial direct current (DC) conductivity stemming from the chiral current and the normal DC conductivity. We find that the axial conduct...

  3. Chiral symmetry on the lattice

    Energy Technology Data Exchange (ETDEWEB)

    Creutz, M.

    1994-11-01

    The author reviews some of the difficulties associated with chiral symmetry in the context of a lattice regulator. The author discusses the structure of Wilson Fermions when the hopping parameter is in the vicinity of its critical value. Here one flavor contrasts sharply with the case of more, where a residual chiral symmetry survives anomalies. The author briefly discusses the surface mode approach, the use of mirror Fermions to cancel anomalies, and finally speculates on the problems with lattice versions of the standard model.

  4. Mechanical chirality: A chiral catalyst with a ring to it

    Science.gov (United States)

    Goldup, Stephen M.

    2016-05-01

    A chiral [2]rotaxane in which the asymmetry is derived from the way in which the two components are mechanically interlocked -- rather than being encoded in the covalent connectivity of the components themselves -- has been shown to act as an enantioselective organocatalyst.

  5. Scaling laws in chiral hydrodynamic turbulence

    CERN Document Server

    Yamamoto, Naoki

    2016-01-01

    We study the turbulent regime of chiral (magneto)hydrodynamics for charged and neutral matter with chirality imbalance. We find that the chiral magnetohydrodynamics for charged plasmas possesses a unique scaling symmetry only without fluid helicity under the local charge neutrality. We also find a different type of unique scaling symmetry in the chiral hydrodynamics for neutral matter with fluid helicity in the inertial range. We show that these symmetries dictate the self-similar inverse cascade of the magnetic and kinetic energies. Our results imply the possible inverse energy cascade in core-collapse supernovae due to the chiral transport of neutrinos.

  6. Chiral magnetic effect in the PNJL model

    CERN Document Server

    Fukushima, Kenji; Gatto, Raoul

    2010-01-01

    We study the two-flavor Nambu--Jona-Lasinio model with the Polyakov loop (PNJL model) in the presence of a strong magnetic field and a chiral chemical potential $\\mu_5$ which mimics the effect of imbalanced chirality due to QCD instanton and/or sphaleron transitions. Firstly we focus on the properties of chiral symmetry breaking and deconfinement crossover under the strong magnetic field. Then we discuss the role of $\\mu_5$ on the phase structure. Finally the chirality charge, electric current, and their susceptibility, which are relevant to the Chiral Magnetic Effect, are computed in the model.

  7. K stability and stability of chiral ring

    CERN Document Server

    Collins, Tristan C; Yau, Shing-Tung

    2016-01-01

    We define a notion of stability for chiral ring of four dimensional N=1 theory by introducing test chiral rings and generalized a maximization. We conjecture that a chiral ring is the chiral ring of a superconformal field theory if and only if it is stable. We then study N=1 field theory derived from D3 branes probing a three-fold singularity X, and show that the K stability which implies the existence of Ricci-flat conic metric on X is equivalent to the stability of chiral ring of the corresponding field theory.

  8. Scaling laws in chiral hydrodynamic turbulence

    Science.gov (United States)

    Yamamoto, Naoki

    2016-06-01

    We study the turbulent regime of chiral (magneto)hydrodynamics for charged and neutral matter with chirality imbalance. We find that the chiral magnetohydrodynamics for charged plasmas possesses a unique scaling symmetry, only without fluid helicity under the local charge neutrality. We also find a different type of unique scaling symmetry in the chiral hydrodynamics for neutral matter with fluid helicity in the inertial range. We show that these symmetries dictate the self-similar inverse cascade of the magnetic and kinetic energies. Our results imply the possible inverse energy cascade in core-collapse supernovae due to the chiral transport of neutrinos.

  9. Thermal chiral vortical and magnetic waves: new excitation modes in chiral fluids

    CERN Document Server

    Kalaydzhyan, Tigran

    2016-01-01

    In certain circumstances, chiral (parity-violating) medium can be described hydrodynamically as a chiral fluid with microscopic quantum anomalies. Possible examples of such systems include strongly coupled quark-gluon plasma, liquid helium 3He-A, neutron stars and the Early Universe. We study first-order hydrodynamics of a chiral fluid on a vortex background and in a external magnetic field. We show that there are two previously undiscovered modes describing heat waves propagating along the vortex and magnetic field. We call them the Thermal Chiral Vortical Wave and Thermal Chiral Magnetic Wave. We also identify known gapless excitations of density, the chiral vortical and chiral magnetic waves. We demonstrate that the velocity of the chiral vortical wave is zero, when the full hydrodynamic framework is applied, and hence the excitation reduces to a charge diffusion mode or is completely absent. We also correct the dispersion relation for the chiral magnetic wave.

  10. Casimir-Polder Forces between Chiral Objects

    CERN Document Server

    Butcher, David T; Scheel, Stefan

    2012-01-01

    The chiral component of the Casimir-Polder potential is derived within the framework of macroscopic quantum electrodynamics. It is shown to exist only if the particle and the medium are both chiral. Furthermore, the chiral component of the Casimir-Polder potential can be attractive or repulsive, depending on the chirality of the molecule and the medium. The theory is applied to a cavity geometry in the non-retarded limit with the intention of enantiomer separation. For a ground state molecule the chiral component is dominated by the electric component and thus no explicit separation will happen. If the molecule is initially in an excited state the electric component of the Casimir-Polder force can be suppressed by an appropriate choice of material and the chiral component can select the molecule based on its chirality, allowing enantiomeric separation to occur.

  11. Casimir–Polder forces between chiral objects

    International Nuclear Information System (INIS)

    The chiral component of the Casimir–Polder potential is derived within the framework of macroscopic quantum electrodynamics. It is shown to exist only if the particle and the medium are both chiral. Furthermore, the chiral component of the Casimir–Polder potential can be attractive or repulsive, depending on the chirality of the molecule and the medium. The theory is applied to a cavity geometry in the non-retarded limit with the intention of enantiomer separation. For a ground state molecule the chiral component is dominated by the electric component and thus no explicit separation will happen. If the molecule is initially in an excited state the electric component of the Casimir–Polder force can be suppressed by an appropriate choice of material and the chiral component can select the molecule based on its chirality, allowing enantiomeric separation to occur. (paper)

  12. Chiral Cosmological Models: Dark Sector Fields Description

    CERN Document Server

    Chervon, S V

    2014-01-01

    The present review is devoted to a Chiral Cosmological Model as the self-gravitating nonlinear sigma model with the potential of (self)interactions employed in cosmology. The chiral cosmological model has successive applications in descriptions of the inflationary epoch of the Universe evolution; the present accelerated expansion of the Universe also can be described by the chiral fields multiplet as the dark energy in wide sense. To be more illustrative we are often addressed to the two-component chiral cosmological model. Namely, the two-component chiral cosmological model describing the phantom field with interaction to a canonical scalar field is analyzed in details. New generalized model of quintom character is proposed and exact solutions are founded out. In the review we represented the perturbation theory for chiral cosmological model with the aim to describe the structure formation using the progress achieved in the inflation theory. It was shown that cosmological perturbations from chiral fields can...

  13. Chirality effect in disordered graphene ribbon junctions

    International Nuclear Information System (INIS)

    We investigate the influence of edge chirality on the electronic transport in clean or disordered graphene ribbon junctions. By using the tight-binding model and the Landauer-Büttiker formalism, the junction conductance is obtained. In the clean sample, the zero-magnetic-field junction conductance is strongly chirality-dependent in both unipolar and bipolar ribbons, whereas the high-magnetic-field conductance is either chirality-independent in the unipolar or chirality-dependent in the bipolar ribbon. Furthermore, we study the disordered sample in the presence of magnetic field and find that the junction conductance is always chirality-insensitive for both unipolar and bipolar ribbons with adequate disorders. In addition, the disorder-induced conductance plateaus can exist in all chiral bipolar ribbons provided the disorder strength is moderate. These results suggest that we can neglect the effect of edge chirality in fabricating electronic devices based on the magnetotransport in a disordered graphene ribbon. (paper)

  14. The chiral symplectic universality class

    OpenAIRE

    Asada, Yoichi; Slevin, Keith; Ohtsuki, Tomi

    2003-01-01

    We report a numerical investigation of localization in the SU(2) model without diagonal disorder. At the band center, chiral symmetry plays an important role. Our results indicate that states at the band center are critical. States away from the band center but not too close to the edge of the spectrum are metallic as expected for Hamiltonians with symplectic symmetry.

  15. Chiral symmetry in perturbative QCD

    International Nuclear Information System (INIS)

    The chiral symmetry of quantum chromodynamics with massless quarks is unbroken in perturbation theory. Dimensional regularization is used. The ratio of the vector and axial vector renormalization constante is shown to be independent of the renormalization mass. The general results are explicitly verified to fourth order in g, the QCD coupling constant

  16. Dynamics of the chiral transition

    International Nuclear Information System (INIS)

    Measurements of disoriented chiral condensates (DCC) in heavy ion collisions at RHIC can yield fundamental information on the nature of the QCD phase transition. I review theoretical efforts to understand DCC formation and present work in progress on possible experimental ramifications

  17. Instantons and chiral symmetry breaking

    International Nuclear Information System (INIS)

    A detailed investigation of chiral symmetry breaking due to instanton dynamics is carried out, within the framework of the dilute gas approximation, for quarks in both the fundamental and adjoint representations of SU(2). The momentum dependence of the dynamical mass is found to be very similar in each representation. (orig.)

  18. Algebraic study of chiral anomalies

    Indian Academy of Sciences (India)

    Juan Mañes; Raymond Stora; Bruno Zumino

    2012-06-01

    The algebraic structure of chiral anomalies is made globally valid on non-trivial bundles by the introduction of a fixed background connection. Some of the techniques used in the study of the anomaly are improved or generalized, including a systematic way of generating towers of ‘descent equations’.

  19. Asymmetric Synthesis via Chiral Aziridines

    DEFF Research Database (Denmark)

    Tanner, David Ackland; Harden, Adrian; Wyatt, Paul; Andersson, Pher G.; Johansson, Fredrik

    1996-01-01

    A series of chiral bis(aziridines) has been synthesised and evaluated as chelating ligands for a variety of asymmetric transformations mediated by metals [Os (dihydroxylation), Pd (allylic alkylation) Cu (cyclopropanation and aziridination, Li (1,2-addition of organolithiums to imines)]. In the...

  20. Chiral Lagrangian and chiral quark model from confinement in QCD

    CERN Document Server

    Simonov, Yu A

    2015-01-01

    The effective chiral Lagrangian in both nonlocal form $L_{ECCL}$ and standard local form $L_{ECL}$ are derived in QCD using the confining kernel, obtained in the vacuum correlator formalism. As a result all coefficients of $L_{ECL}$ can be computed via $q\\bar q$ Green's functions. In the $p^2$ order of $L_{ECL}$ one obtains GOR relations and quark decay constants $f_a$ are calculated $a=1,...8$, while in the $p^4$ order the coefficients $L_1, L_2, L_3,L_4, L_5, L_6$ are obtained in good agreement with the values given by data. The chiral quark model is shown to be a simple consequence of $L_{ECCL}$ with defined coefficients. It is demonstrated that $L_{ECCL}$ gives an extension of the limiting low-energy Lagrangian $L_{ECL}$ to arbitrary momenta.

  1. Spectral study of a chiral limit without chiral condensate

    CERN Document Server

    Bietenholz, Wolfgang

    2009-01-01

    Random Matrix Theory (RMT) has elaborated successful predictions for Dirac spectra in field theoretical models. However, a generic assumption by RMT has been a non-vanishing chiral condensate $\\Sigma$ in the chiral limit. Here we consider the 2-flavour Schwinger model, where this assumption does not hold. We simulated this model with dynamical overlap hypercube fermions, and entered terra incognita by analysing this Dirac spectrum. The usual RMT prediction for the unfolded level spacing distribution in a unitary ensemble is precisely confirmed. The microscopic spectrum does not perform a Banks-Casher plateau. Instead the obvious expectation is a density of the lowest eigenvalue $\\lambda_{1}$ which increases $\\propto \\lambda_{1}^{1/3}$. That would correspond to a scale-invariant parameter $\\propto \\lambda V^{3/4}$, which is, however, incompatible with our data. Instead we observe to high precision a scale-invariant parameter $z \\propto \\lambda V^{5/8}$. This surprising result implies a microscopic spectral den...

  2. Chiral logarithms in quenched QCD

    International Nuclear Information System (INIS)

    The quenched chiral logarithms are examined on a 163x28 lattice with Iwasaki gauge action and overlap fermions. The pion decay constant fpi is used to set the lattice spacing, a = 0.200(3) fm. With pion mass as low as ∼180 MeV, we see the quenched chiral logarithms clearly in mpi2/m and fP, the pseudoscalar decay constant. The authors analyze the data to determine how low the pion mass needs to be in order for the quenched one-loop chiral perturbation theory (chiPT) to apply. With the constrained curve-fitting method, they are able to extract the quenched chiral logarithmic parameter delta together with other low-energy parameters. Only for mpi<=300 MeV do we obtain a consistent and stable fit with a constant delta which they determine to be 0.24(3)(4) (at the chiral scale Lambdachi = 0.8 GeV). By comparing to the 123x28 lattice, they estimate the finite volume effect to be about 2.7% for the smallest pion mass. They also fitted the pion mass to the form for the re-summed cactus diagrams and found that its applicable region is extended farther than the range for the one-loop formula, perhaps up to mpi ∼500-600 MeV. The scale independent delta is determined to be 0.20(3) in this case. The authors study the quenched non-analytic terms in the nucleon mass and find that the coefficient C1/2 in the nucleon mass is consistent with the prediction of one-loop chiPT. They also obtain the low energy constant L5 from fpi. They conclude from this study that it is imperative to cover only the range of data with the pion mass less than ∼300 MeV in order to examine the chiral behavior of the hadron masses and decay constants in quenched QCD and match them with quenched one-loop chiPT

  3. Focusing, Power Tunneling and Rejection from Chiral and/or Chiral Nihility/Nihility Metamaterials Layers

    CERN Document Server

    Shah, Syed Touseef Hussain; Syed, Aqeel A; Naqvi, Qaisar Abbas

    2013-01-01

    Focusing of electromagnetic plane wave from a large size paraboloidal reflector, composed of layers of chiral and/or chiral nihility metamaterials, has been studied us- ing Maslov's method. First, the transmission and reflection of electromagnetic plane wave from two parallel layers of chiral and/or chiral nihility metamaterials are cal- culated using transfer matrix method. The effects of change of angle of incidence, chirality parameters and impedances of layers are noted and discussed. Special cases by taking very large and small values of permittivity of second layer, while assuming value of corresponding chirality equal to zero, are also treated. These special cases are equivalent to reflection from a perfect electric conductor backed chiral layer and nihility backed chiral layer, respectively. Results of reflection from parallel layers have been utilized to study focusing from a large size paraboloidal reflector. The present study, on focusing from a paraboloidal re{\\deg}ector, not only unifies several ...

  4. Chiral Negative-Index Metamaterials in Terahertz

    CERN Document Server

    Zhang, Shuang; Li, Jensen; Lu, Xinchao; Zhang, Weili; Zhang, Xiang

    2008-01-01

    Negative index metamaterials (NIMs) give rise to unusual and intriguing properties and phenomena, which may lead to important applications such as superlens, subwavelength cavity and slow light devices. However, the negative refractive index in metamaterials normally requires a stringent condition of simultaneously negative permittivity and negative permeability. A new class of negative index metamaterials - chiral NIMs, have been recently proposed. In contrast to the conventional NIMs, chiral NIMs do not require the above condition, thus presenting a very robust route toward negative refraction. Here we present the first experimental demonstration of a chiral metamaterial exhibiting negative refractive index down to n=-5 at terahertz frequencies, with only a single chiral resonance. The strong chirality present in the structure lifts the degeneracy for the two circularly polarized waves and relieves the double negativity requirement. Chiral NIM are predicted to possess intriguing electromagnetic properties t...

  5. Stable Pentaquarks from Strange Chiral Multiplets

    Energy Technology Data Exchange (ETDEWEB)

    Silas Beane

    2004-12-01

    The assumption of strong diquark correlations in the QCD spectrum suggests flavor multiplets of hadrons that are degenerate in the chiral limit. Generally it would be unnatural for there to be degeneracy in the hadron spectrum that is not protected by a QCD symmetry. Here we show--for pentaquarks constructed from diquarks--that these degeneracies can be naturally protected by the full chiral symmetry of QCD. The resulting chiral multiplet structure recovers the ideally-mixed pentaquark mass spectrum of the diquark model, and interestingly, requires that the axial couplings of the pentaquarks to states outside the degenerate multiplets vanish in the chiral limit. This result suggests that if these hadrons exist, they are stable in the chiral limit and therefore have widths that scale as the fourth power of the kaon mass over the chiral symmetry breaking scale. Natural-size widths are of order a few MeV.

  6. Anomalous Maxwell equations for inhomogeneous chiral plasma

    CERN Document Server

    Gorbar, E V; Vilchinskii, S; Rudenok, I; Boyarsky, A; Ruchayskiy, O

    2016-01-01

    Using the chiral kinetic theory we derive the electric and chiral current densities in inhomogeneous relativistic plasma. We also derive equations for the electric and chiral charge chemical potentials that close the Maxwell equations in such a plasma. The analysis is done in the regimes with and without a drift of the plasma as a whole. In addition to the currents present in the homogeneous plasma (Hall current, chiral magnetic, chiral separation, and chiral electric separation effects, as well as Ohm's current) we derive several new terms associated with inhomogeneities of the plasma. Apart from various diffusion-like terms, we find also new dissipation-less terms that are independent of relaxation time. Their origin can be traced to the Berry curvature modifications of the kinetic theory.

  7. Chiral Symmetry Restoration from a Boundary

    CERN Document Server

    Tiburzi, B C

    2013-01-01

    The boundary of a manifold can alter the phase of a theory in the bulk. We explore the possibility of a boundary-induced phase transition for the chiral symmetry of QCD. In particular, we investigate the consequences of imposing homogeneous Dirichlet boundary conditions on the quark fields. Such boundary conditions are employed on occasion in lattice gauge theory computations, for example, when including external electromagnetic fields, or when computing quark propagators with a reduced temporal extent. Homogeneous Dirichlet boundary conditions force the chiral condensate to vanish at the boundary, and thereby obstruct the spontaneous breaking of chiral symmetry in the bulk. As the restoration of chiral symmetry due to a boundary is a non-perturbative phenomenon, we utilize the sigma model to exemplify the issues. Using this model, we find that chiral symmetry is completely restored if the length of the compact direction is less than 2.0 fm. For lengths greater than about 4 fm, an approximately uniform chiral...

  8. Asymmetric synthesis using chiral-encoded metal.

    Science.gov (United States)

    Yutthalekha, Thittaya; Wattanakit, Chularat; Lapeyre, Veronique; Nokbin, Somkiat; Warakulwit, Chompunuch; Limtrakul, Jumras; Kuhn, Alexander

    2016-01-01

    The synthesis of chiral compounds is of crucial importance in many areas of society and science, including medicine, biology, chemistry, biotechnology and agriculture. Thus, there is a fundamental interest in developing new approaches for the selective production of enantiomers. Here we report the use of mesoporous metal structures with encoded geometric chiral information for inducing asymmetry in the electrochemical synthesis of mandelic acid as a model molecule. The chiral-encoded mesoporous metal, obtained by the electrochemical reduction of platinum salts in the presence of a liquid crystal phase and the chiral template molecule, perfectly retains the chiral information after removal of the template. Starting from a prochiral compound we demonstrate enantiomeric excess of the (R)-enantiomer when using (R)-imprinted electrodes and vice versa for the (S)-imprinted ones. Moreover, changing the amount of chiral cavities in the material allows tuning the enantioselectivity. PMID:27562028

  9. Phases of chiral gauge theories

    International Nuclear Information System (INIS)

    We discuss the behavior of two non-supersymmetric chiral SU(N) gauge theories, involving fermions in the symmetric and antisymmetric two-index tensor representations respectively. In addition to global anomaly matching, we employ a recently proposed inequality constraint on the number of effective low energy (massless) degrees of freedom of a theory, based on the thermodynamic free energy. Several possible zero temperature phases are consistent with the constraints. A simple picture for the phase structure emerges if these theories choose the phase, consistent with global anomaly matching, that minimizes the massless degree of freedom count defined through the free energy. This idea suggests that confinement with the preservation of the global symmetries through the formation of massless composite fermions is in general not preferred. While our discussion is restricted mainly to bilinear condensate formation, higher dimensional condensates are considered for one case. We conclude by commenting briefly on two related supersymmetric chiral theories. (c) 2000 The American Physical Society

  10. Bootstrapping N=2 chiral correlators

    Science.gov (United States)

    Lemos, Madalena; Liendo, Pedro

    2016-01-01

    We apply the numerical bootstrap program to chiral operators in four-dimensional N=2 SCFTs. In the first part of this work we study four-point functions in which all fields have the same conformal dimension. We give special emphasis to bootstrapping a specific theory: the simplest Argyres-Douglas fixed point with no flavor symmetry. In the second part we generalize our setup and consider correlators of fields with unequal dimension. This is an example of a mixed correlator and allows us to probe new regions in the parameter space of N=2 SCFTs. In particular, our results put constraints on relations in the Coulomb branch chiral ring and on the curvature of the Zamolodchikov metric.

  11. Bootstrapping N=2 chiral correlators

    Energy Technology Data Exchange (ETDEWEB)

    Lemos, Madalena [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Liendo, Pedro [Humboldt-Univ. Berlin (Germany). IMIP

    2015-12-15

    We apply the numerical bootstrap program to chiral operators in four-dimensional N=2 SCFTs. In the first part of this work we study four-point functions in which all fields have the same conformal dimension. We give special emphasis to bootstrapping a specific theory: the simplest Argyres-Douglas fixed point with no flavor symmetry. In the second part we generalize our setup and consider correlators of fields with unequal dimension. This is an example of a mixed correlator and allows us to probe new regions in the parameter space of N=2 SCFTs. In particular, our results put constraints on relations in the Coulomb branch chiral ring and on the curvature of the Zamolodchikov metric.

  12. Homogenization of resonant chiral metamaterials

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Menzel, C.; Rockstuhl, Carsten;

    2010-01-01

    Homogenization of metamaterials is a crucial issue as it allows to describe their optical response in terms of effective wave parameters as, e.g., propagation constants. In this paper we consider the possible homogenization of chiral metamaterials. We show that for meta-atoms of a certain size a...... critical density exists above which increasing coupling between neighboring meta-atoms prevails a reasonable homogenization. On the contrary, a dilution in excess will induce features reminiscent to photonic crystals likewise prevailing a homogenization. Based on Bloch mode dispersion we introduce an...... analytical criterion for performing the homogenization and a tool to predict the homogenization limit. We show that strong coupling between meta-atoms of chiral metamaterials may prevent their homogenization at all....

  13. Bootstrapping N=2 chiral correlators

    International Nuclear Information System (INIS)

    We apply the numerical bootstrap program to chiral operators in four-dimensional N=2 SCFTs. In the first part of this work we study four-point functions in which all fields have the same conformal dimension. We give special emphasis to bootstrapping a specific theory: the simplest Argyres-Douglas fixed point with no flavor symmetry. In the second part we generalize our setup and consider correlators of fields with unequal dimension. This is an example of a mixed correlator and allows us to probe new regions in the parameter space of N=2 SCFTs. In particular, our results put constraints on relations in the Coulomb branch chiral ring and on the curvature of the Zamolodchikov metric.

  14. On chirality of slime mould.

    Science.gov (United States)

    Dimonte, Alice; Adamatzky, Andrew; Erokhin, Victor; Levin, Michael

    2016-02-01

    Left-right patterning and lateralised behaviour is an ubiquitous aspect of plants and animals. The mechanisms linking cellular chirality to the large-scale asymmetry of multicellular structures are incompletely understood, and it has been suggested that the chirality of living cells is hardwired in their cytoskeleton. We examined the question of biased asymmetry in a unique organism: the slime mould Physarum polycephalum, which is unicellular yet possesses macroscopic, complex structure and behaviour. In laboratory experiment using a T-shape, we found that Physarum turns right in more than 74% of trials. The results are in agreement with previously published studies on asymmetric movement of muscle cells, neutrophils, liver cells and growing neural filaments, and for the first time reveal the presence of consistently-biased laterality in the fungi kingdom. Exact mechanisms of the slime mould's direction preference remain unknown. PMID:26747637

  15. An epistemological note on chirality

    International Nuclear Information System (INIS)

    The terms ''chiral'' and ''achiral'' are sharply defined when applied to geometric figures or models. The same terms are also commonly used to refer to the real systems to which these models have been adjoined. e.g., molecules, solvents, or reagents. Here, the terms are not sharply defined but depend upon conditions or measurement. The contrast between the geometric and operational usages is discussed in detail

  16. Chiral Primaries in Strange Metals

    OpenAIRE

    Isachenkov, Mikhail(DESY Hamburg, Theory Group, Notkestrasse 85, D-22607 Hamburg, Germany); Kirsch, Ingo; Schomerus, Volker

    2014-01-01

    It was suggested recently that the study of 1-dimensional QCD with fermions in the adjoint representation could lead to an interesting toy model for strange metals and their holographic formulation. In the high density regime, the infrared physics of this theory is described by a constrained free fermion theory with an emergent N=(2,2) superconformal symmetry. In order to narrow the choice of potential holographic duals, we initiate a systematic search for chiral primaries in this model. We a...

  17. Chiral Lagrangians and the SSC

    International Nuclear Information System (INIS)

    In the event that the SSC does not observe any resonances such as a Higgs boson or a techni-rho meson, we would like to know if the SSC can still discover something about the nature of the electroweak symmetry breaking. We will use chiral Lagrangian techniques to address this question and analyze their utility for studying events containing W and Z gauge bosons at the SSC. 20 refs., 4 figs

  18. Chiral symmetry and nucleon structure

    Energy Technology Data Exchange (ETDEWEB)

    Holstein, B.R. (Massachusetts Univ., Amherst, MA (United States). Dept. of Physics and Astromony Washington Univ., Seattle, WA (United States). Inst. for Nuclear Theory)

    1992-01-01

    Recently it has been realized that significant tests of the validity of QCD are available in low energy experiments (E < 500 MeV) by exploiting the property of (broken) chiral symmetry. This technique has been highly developed in The Goldstone boson sector by the work of Gasser and Leutwyler. Application to the nucleon system is much more difficult and is now being carefully developed.

  19. Chiral solitons a review volume

    CERN Document Server

    1987-01-01

    This review volume on topological and nontopological chiral solitons presents a global view on the current developments of this field in particle and nuclear physics. The book addresses problems in quantization, restoration of translational and rotational symmetry, and the field theoretical approach to solitons which are common problems in the field of solitons. Primarily aimed for graduate students and the novice in the field, the collected articless cover a broad spectrum of topics in formalism as well as phenomenology.

  20. Majorana Neutrino: Chirality and Helicity

    CERN Document Server

    Dvoeglazov, Valeriy V

    2012-01-01

    We introduce the Majorana spinors in the momentum representation. They obey the Dirac-like equation with eight components, which has been first introduced by Markov. Thus, the Fock space for corresponding quantum fields is doubled (as shown by Ziino). Particular attention has been paid to the questions of chirality and helicity (two concepts which frequently are confused in the literature) for Dirac and Majorana states.

  1. Staggered chiral random matrix theory

    International Nuclear Information System (INIS)

    We present a random matrix theory for the staggered lattice QCD Dirac operator. The staggered random matrix theory is equivalent to the zero-momentum limit of the staggered chiral Lagrangian and includes all taste breaking terms at their leading order. This is an extension of previous work which only included some of the taste breaking terms. We will also present some results for the taste breaking contributions to the partition function and the Dirac eigenvalues.

  2. Chiral Particle Separation by a Nonchiral Microlattice

    Science.gov (United States)

    Bogunovic, Lukas; Fliedner, Marc; Eichhorn, Ralf; Wegener, Sonja; Regtmeier, Jan; Anselmetti, Dario; Reimann, Peter

    2012-09-01

    We conceived a model experiment for a continuous separation strategy of chiral molecules (enantiomers) without the need of any chiral selector structure or derivatization agents: Microparticles that only differ by their chirality are shown to migrate along different directions when driven by a steady fluid flow through a square lattice of cylindrical posts. In accordance with our numerical predictions, the transport directions of the enantiomers depend very sensitively on the orientation of the lattice relative to the fluid flow.

  3. Enantiomeric Separations using Chiral Counter-Ions

    OpenAIRE

    Haglöf, Jakob

    2010-01-01

    This thesis describes the use of chiral counter-ions for the enantiomeric separation of amines in non-aqueous capillary electrophoresis. The investigations have been concentrated on studies of the influence, of the chiral counter-ion, the solvent, the electrolyte and the analyte, on the enantioselective separation. Modified divalent dipeptides have been introduced in capillary electrophoresis for the separation of amino alcohols and chiral resolution of amines. Association constants for the i...

  4. Chiral Seismic Attenuation with Acoustic Metamaterials

    OpenAIRE

    Hector Torres-Silva; Diego Torres Cabezas

    2013-01-01

    We study the analogy between the linear elasticity theory equations and classical Maxwell equation with chiral effects and we propose a new method of an earthquake-resistant design to support conventional aseismic designs using acoustic metamaterials. We suggest a simple and practical method to reduce the amplitude of a seismic wave exponentially. Our device is like an attenuator of a chiral seismic wave. Constructing a cylindrical shell-type waveguide that creates a stop-band for the chiral...

  5. Chiral magnetic effect by synthetic gauge fields

    CERN Document Server

    Hayata, Tomoya

    2016-01-01

    We study the dynamical generation of the chiral chemical potential in a Weyl metal constructed from a three-dimensional optical lattice and subject to synthetic gauge fields. By numerically solving the Boltzmann equation with the Berry curvature in the presence of parallel synthetic electric and magnetic fields, we find that the spectral flow and the ensuing chiral magnetic current emerge. We show that the spectral flow and the chiral chemical potential can be probed by time-of-flight imaging.

  6. Random Matrix Theory and Chiral Logarithms

    OpenAIRE

    Berbenni-Bitsch, M. E.; Göckeler, M.; Hehl, H.; Meyer, S.; Rakow, P. E. L.; Schäfer, A.; Wettig, T.

    1999-01-01

    Abstract: Recently, the contributions of chiral logarithms predicted by quenched chiral perturbation theory have been extracted from lattice calculations of hadron masses. We argue that a detailed comparison of random matrix theory and lattice calculations allows for a precise determination of such corrections. We estimate the relative size of the m log(m), m, and m^2 corrections to the chiral condensate for quenched SU(2).

  7. The chirality operators for Heisenberg spin systems

    International Nuclear Information System (INIS)

    The ground state of closed Heisenberg spin chains with an odd number of sites has a chiral degeneracy, in addition to a two-fold Kramers degeneracy. A non-zero chirality implies that the spins are not coplanar, and is a measure of handedness. The chirality operator, which can be treated as a spin-1/2 operator, is explicitly constructed in terms of the spin operators, and is given as commutator of permutation operators. (author). 3 refs

  8. Chiral symmetry breaking and monopoles

    CERN Document Server

    Di Giacomo, Adriano; Pucci, Fabrizio

    2015-01-01

    To understand the relation between the chiral symmetry breaking and monopoles, the chiral condensate which is the order parameter of the chiral symmetry breaking is calculated in the $\\overline{\\mbox{MS}}$ scheme at 2 [GeV]. First, we add one pair of monopoles, varying the monopole charges $m_{c}$ from zero to four, to SU(3) quenched configurations by a monopole creation operator. The low-lying eigenvalues of the Overlap Dirac operator are computed from the gauge links of the normal configurations and the configurations with additional monopoles. Next, we compare the distributions of the nearest-neighbor spacing of the low-lying eigenvalues with the prediction of the random matrix theory. The low-lying eigenvalues not depending on the scale parameter $\\Sigma$ are compared to the prediction of the random matrix theory. The results show the consistency with the random matrix theory. Thus, the additional monopoles do not affect the low-lying eigenvalues. Moreover, we discover that the additional monopoles increa...

  9. Chiral symmetry and functional integral

    Energy Technology Data Exchange (ETDEWEB)

    Gamboa Saravi, R.E.; Muschietti, M.A.; Schaposnik, F.A.; Solomin, J.E.

    1984-10-15

    The change in the fermionic functional integral measure under chiral rotations is analyzed. Using the zeta-function method, the evaluation of chiral Jacobians to theories including non-hermitian Dirac operators D, can be extended in a natural way. (This being of interest, for example, in connection with the Weinberg-Salam model or with the relativistic string theory). Results are compared with those obtained following other approaches, the possible discrepancies are analyzed and the equivalence of the different methods under certain conditions on D is proved. Also shown is how to compute the Jacobian for the case of a finite chiral transformation and this result is used to develop a sort of path-integral version of bosonization in d = 2 space-time dimensions. This result is used to solve in a very simple and economical way relevant d = 2 fermionic models. Furthermore, some interesting features in connection with the theta-vacuum in d = 2,4 gauge theories are discussed.

  10. Lateral chirality-sorting optical forces

    Science.gov (United States)

    Hayat, Amaury; Mueller, J. P. Balthasar; Capasso, Federico

    2015-01-01

    The transverse component of the spin angular momentum of evanescent waves gives rise to lateral optical forces on chiral particles, which have the unusual property of acting in a direction in which there is neither a field gradient nor wave propagation. Because their direction and strength depends on the chiral polarizability of the particle, they act as chirality-sorting and may offer a mechanism for passive chirality spectroscopy. The absolute strength of the forces also substantially exceeds that of other recently predicted sideways optical forces. PMID:26453555

  11. Implications of Local Chiral Symmetry Breaking

    CERN Document Server

    La, H S

    2003-01-01

    The spontaneous symmetry breaking of a local chiral symmetry to its diagonal vector symmetry naturally realizes a complete geometrical structure more general than that of Yang-Mills (YM) theory, rather similar to that of gravity. A good example is the Quantum Chromodynamics (QCD) with respect to the Chiral Color model. Also, a new anomaly-free particle content for a Chiral Color model is introduced: the Chiral Color can be realized without introducing whole new generations of quarks and leptons, but by simply enlarging each generation with new exotic fermions.

  12. The Optical Chirality Flux as a Useful Far-Field Probe of Chiral Near Fields

    CERN Document Server

    Poulikakos, Lisa V; McPeak, Kevin M; Burger, Sven; Niegemann, Jens; Hafner, Christian; Norris, David J

    2016-01-01

    To optimize the interaction between chiral matter and highly twisted light, quantities that can help characterize chiral electromagnetic fields near nanostructures are needed. Here, by analogy with Poynting's theorem, we formulate the time-averaged conservation law of optical chirality in lossy dispersive media and identify the optical chirality flux as an ideal far-field observable for characterizing chiral optical near fields. Bounded by the conservation law, we show that it provides precise information, unavailable from circular dichroism spectroscopy, on the magnitude and handedness of highly twisted fields near nanostructures.

  13. Scaling behaviour of the effective chiral action and stability of the chiral soliton

    International Nuclear Information System (INIS)

    The effective chiral action is evaluated within a novel improved heat-kernel expansion, which includes gradients of the chiral field in a non-perturbative way. The exact scaling behaviour of the effective action of a localized chiral field with respect to changing its spatial size is found. From this it is proved that the radiatively induced derivative terms cannot absolutely stabilize the chiral soliton against collapsing. The collapsing of the soliton is, however, accompanied by a vanishing of the baryon charge. It is argued that the effective chiral action constrained to a fixed baryon number may still admit stable soliton configurations. (orig.)

  14. Synthesis and Chiral Recognition of a New Type of Chiral Calix[4]arene Derivatives

    Institute of Scientific and Technical Information of China (English)

    HE,Yong-Bing; LI,Jian-Feng; XIAO,Yuan-Jing; WEI,Lan-Hua; WU,Xiao-Jun; MENG,Ling-Zhi

    2003-01-01

    Two new chiral calix[4] arenes bearing chiral pendants, which were from by-product of the antibiotic industry, were synthesized and characterized by 1H NMR, MS-FAB and elemental analysis. Studies of 1H NMR of the two calix [4] arene derivatives indicate that they exist in cone conformation in solution. Results of chiral recognition of the two chiral ligands 2a and 2b towards the tartaric acid derivative 3 show that ligand 2a exhibited good chiral recognition abilities compared to ligand 2b.

  15. Chirally-modified metal surfaces: energetics of interaction with chiral molecules.

    Science.gov (United States)

    Dementyev, Petr; Peter, Matthias; Adamovsky, Sergey; Schauermann, Swetlana

    2015-09-21

    Imparting chirality to non-chiral metal surfaces by adsorption of chiral modifiers is a highly promising route to create effective heterogeneously catalyzed processes for the production of enantiopure pharmaceuticals. One of the major current challenges in heterogeneous chiral catalysis is the fundamental-level understanding of how such chirally-modified surfaces interact with chiral and prochiral molecules to induce their enantioselective transformations. Herein we report the first direct calorimetric measurement of the adsorption energy of chiral molecules onto well-defined chirally-modified surfaces. Two model modifiers 1-(1-naphthyl)ethylamine and 2-methylbutanoic acid were used to impart chirality to Pt(111) and their interaction with propylene oxide was investigated by means of single-crystal adsorption calorimetry. Differential adsorption energies and absolute surface uptakes were obtained for the R- and S-enantiomers of propylene oxide under clean ultrahigh vacuum conditions. Two types of adsorption behavior were observed for different chiral modifiers, pointing to different mechanisms of imparting chirality to metal surfaces. The results are analyzed and discussed in view of previously reported stereoselectivity of adsorption processes. PMID:26256836

  16. Hydrodynamics of Liquids of Chiral Molecules and Suspensions Containing Chiral Particles

    Science.gov (United States)

    Andreev, A. V.; Son, D. T.; Spivak, B.

    2010-05-01

    We obtain hydrodynamic equations describing a fluid consisting of chiral molecules or a suspension of chiral particles in a Newtonian fluid. The hydrodynamic velocity and stresses arising in a flowing chiral liquid have components that are forbidden by symmetry in a Newtonian liquid. For example, a chiral liquid in a Poiseuille flow between parallel plates exerts forces on the plates, which are perpendicular to the flow. A generic flow results in spatial separation of particles of different chirality. Thus even a racemic suspension will exhibit chiral properties in a generic flow. A suspension of particles of random shape in a Newtonian liquid is described by equations which are similar to those describing a racemic mixture of chiral particles in a liquid.

  17. Formation of Enhanced Uniform Chiral Fields in Symmetric Dimer Nanostructures

    CERN Document Server

    Tian, Xiaorui; Sun, Mengtao

    2015-01-01

    Chiral fields with large optical chirality are very important in chiral molecules analysis, sensing and other measurements. Plasmonic nanostructures have been proposed to realize such super chiral fields for enhancing weak chiral signals. However, most of them cannot provide uniform chiral near-fields close to the structures, which makes these nanostructures not so efficient for applications. Plasmonic helical nanostructures and blocked squares have been proved to provide uniform chiral near-fields, but structure fabrication is a challenge. In this paper, we show that very simple plasmonic dimer structures can provide uniform chiral fields in the gaps with large enhancement of both near electric fields and chiral fields under linearly polarized light illumination with polarization off the dimer axis at dipole resonance. 30 times of volume averaged chiral field enhancement is gotten in the whole gap. Chiral fields with opposite handedness can be obtained simply by changing the polarization to the other side of...

  18. A spectral route to determining chirality

    DEFF Research Database (Denmark)

    Pedersen, Jesper Goor; Mortensen, Asger

    2009-01-01

    We show how one-dimensional structured media can be used to measure chirality, via the spectral shift of the photonic band gap edges. Analytically, we show that a chiral contrast can, in some cases, be mapped unto an index contrast, thereby greatly simplifying the analysis of such structures. Using...

  19. Is chiral symmetry manifested in nuclear structure?

    OpenAIRE

    Furnstahl, R. J.; Schwenk, A

    2010-01-01

    Spontaneously broken chiral symmetry is an established property of low-energy quantum chromodynamics, but finding direct evidence for it from nuclear structure data is a difficult challenge. Indeed, phenomenologically successful energy-density functional approaches do not even have explicit pions. Are there smoking guns for chiral symmetry in nuclei?

  20. Partial quenching and chiral symmetry breaking

    OpenAIRE

    Creutz, Michael

    2014-01-01

    Partially quenched chiral perturbation theory assumes that valence quarks propagating on gauge configurations prepared with sea quarks of different masses will form a chiral condensate as the valence quark mass goes to zero. I present a counterexample involving non-degenerate sea quarks where the valence condensate does not form.

  1. Generalized electromagnetic fields in a chiral medium

    Energy Technology Data Exchange (ETDEWEB)

    Bisht, P S [Department of Physics, Kumaun University, Soban Singh Jeena Campus, Almora-263601 (Uttarakhand) (India); Singh, Jivan [Department of Physics, Govt. Post Graduate College, Pithoragarh (Uttarakhand) (India); Negi, O P S [Department of Physics, Kumaun University, Soban Singh Jeena Campus, Almora-263601 (Uttarakhand) (India)

    2007-09-14

    The time-dependent Dirac-Maxwell's equations in the presence of electric and magnetic sources are reformulated in a chiral medium, and the solutions for the classical problem are obtained in a unique, simple and consistent manner. The quaternion reformulation of generalized electromagnetic fields in the chiral medium has also been discussed in a compact, simple and consistent manner.

  2. LINEARLY POLARIZED PROBES OF SURFACE CHIRALITY

    NARCIS (Netherlands)

    VERBIEST, T; KAURANEN, M; MAKI, JJ; TEERENSTRA, MN; SCHOUTEN, AJ; NOLTE, RJM; PERSOONS, A

    1995-01-01

    We present a new nonlinear optical technique to study surface chirality. We demonstrate experimentally that the efficiency of second-harmonic generation from isotropic chiral surfaces is different for excitation with fundamental light that is +45 degrees and -45 degrees linearly polarized with respe

  3. Chiral Anomaly in Toroidal Carbon Nanotubes

    OpenAIRE

    Sasaki, K.

    2001-01-01

    It is pointed out that the chiral anomaly in 1+1 dimensions should be observed in toroidal carbon nanotubes on a planar geometry with varying magnetic field. We show that the chiral anomaly is closely connected with the persistent current in a one-dimensional metallic ring.

  4. Chirally-sensitive electron-molecule interactions

    Science.gov (United States)

    Dreiling, J. M.; Gay, T. J.

    2015-09-01

    All molecular forms of life have chemically-specific handedness. However, the origin of these asymmetries is not understood. A possible explanation was suggested by Vester and Ulbricht immediately following the discovery of parity violation in 1957: chiral beta radiation in cosmic rays may have preferentially destroyed one enantiomeric form of various biological precursors. In the experiments reported here, we observed chiral specificity in two electron- molecule interactions: quasi-elastic scattering and dissociative electron attachment. Using low- energy longitudinally spin-polarized (chiral) electrons as substitutes for beta rays, we found that chiral bromocamphor molecules exhibited both a transmission and dissociative electron attachment rate that depended on their handedness for a given direction of incident electron spin. Consequently, these results, especially those with dissociative electron attachment, connect the universal chiral asymmetry of the weak force with a molecular breakup process, thereby demonstrating the viability of the Vester-Ulbricht hypothesis.

  5. Radiative meson decays in chiral perturbation theory

    International Nuclear Information System (INIS)

    Radiative meson decays are a fertile field for chiral perturbation theory. Chiral symmetry together with gauge invariance yield stringent constraints on radiative decay amplitudes. In addition to predicting decay rates and spectra, the chiral approach allows for a unified description of CP violation in radiative K decays. The chiral viewpoint in the recent controversy over the magnitude of two-photon exchange in the decay KL→ π0e+e- is exposed. The radiative decay η→π0γγ is discussed as an intriguing case where the leading result of chiral perturbation theory seems to be too small by two orders of magnitude in rate. 32 refs., 3 figs. (Author)

  6. Principal chiral model on superspheres

    International Nuclear Information System (INIS)

    We investigate the spectrum of the principal chiral model (PCM) on odd-dimensional superspheres as a function of the curvature radius R. For volume-filling branes on S3verticalstroke2, we compute the exact boundary spectrum as a function of R. The extension to higher dimensional superspheres is discussed, but not carried out in detail. Our results provide very convincing evidence in favor of the strong-weak coupling duality between supersphere PCMs and OSP(2S+2 vertical stroke 2S) Gross-Neveu models that was recently conjectured by Candu and Saleur. (orig.)

  7. Liquids with Chiral Bond Order

    OpenAIRE

    Kamien, Randall

    1995-01-01

    I describe new phases of a chiral liquid crystal with nematic and hexatic order. I find a conical phase, similar to that of a cholesteric in an applied magnetic field for Frank elastic constants $K_2>K_3$. I discuss the role of fluctuations in the context of this phase and the possibility of satisfying the inequality for sufficiently long polymers. In addition I discuss the topological constraint relating defects in the bond order field to textures of the nematic and elucidate its physical me...

  8. Principal chiral model on superspheres

    Energy Technology Data Exchange (ETDEWEB)

    Mitev, V.; Schomerus, V. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Quella, T. [Amsterdam Univ. (Netherlands). Inst. for Theoretical Physics

    2008-09-15

    We investigate the spectrum of the principal chiral model (PCM) on odd-dimensional superspheres as a function of the curvature radius R. For volume-filling branes on S{sup 3} {sup vertical} {sup stroke} {sup 2}, we compute the exact boundary spectrum as a function of R. The extension to higher dimensional superspheres is discussed, but not carried out in detail. Our results provide very convincing evidence in favor of the strong-weak coupling duality between supersphere PCMs and OSP(2S+2 vertical stroke 2S) Gross-Neveu models that was recently conjectured by Candu and Saleur. (orig.)

  9. Chiral Anomaly in Contorted Spacetimes

    CERN Document Server

    Mielke, E W

    1999-01-01

    The Dirac equation in Riemann-Cartan spacetimes with torsion is reconsidered. As is well-known, only the axial covector torsion $A$, a one-form, couples to massive Dirac fields. Using diagrammatic techniques, we show that besides the familiar Riemannian term only the Pontrjagin type four-form $dA\\wedge dA$ does arise additionally in the chiral anomaly, but not the Nieh-Yan term $d ^* A$, as has been claimed recently. Implications for cosmic strings in Einstein-Cartan theory as well as for Ashtekar's canonical approach to quantum gravity are discussed.

  10. Teleporting Superpositions of Chiral Amplitudes

    CERN Document Server

    Maierle, C S; Harris, R A; Maierle, Christopher S.; Lidar, Daniel A.; Harris, Robert A.

    1998-01-01

    Chiral molecules may exist in superpositions of left- and right-handed states. We show how the amplitudes of such superpositions may be teleported to the polarization degrees of freedom of a photon. Two experimental schemes are proposed, one leading to perfect, the other to state-dependent teleportation. Both methods yield complete information about the amplitudes. This is the first explicit example of "inter-species" teleportation, where the amplitudes of the quantum superposition of one species are transferred at the end of the process to a different species. The latter is then easily accessible for measurement.

  11. Nuclear chiral dynamics and thermodynamics

    OpenAIRE

    Holt, J. W.; Kaiser, N.; Weise, W.

    2013-01-01

    This presentation reviews an approach to nuclear many-body systems based on the spontaneously broken chiral symmetry of low-energy QCD. In the low-energy limit, for energies and momenta small compared to a characteristic symmetry breaking scale of order 1 GeV, QCD is realized as an effective field theory of Goldstone bosons (pions) coupled to heavy fermionic sources (nucleons). Nuclear forces at long and intermediate distance scales result from a systematic hierarchy of one- and two-pion exch...

  12. Status of chiral meson physics

    Energy Technology Data Exchange (ETDEWEB)

    Bijnens, Johan [Department of Astronomy and Theoretical Physics, Lund University, Sölvegatan 14A, SE 22362 Lund (Sweden)

    2016-01-22

    This talk includes a short introduction to Chiral Perturbation Theory in the meson sector concentrating on a number of recent developments. I discuss the latest fit of the low-energy constants. Finite volume corrections are discussed for the case with twisted boundary conditions for form-factors and first results at two-loops for three flavours for masses. The last part discusses the extension to other symmetry breaking patterns relevant for technicolour and related theories as well as the calculation of leading logarithms to high loop orders.

  13. Synthesis and characterization of mixed ligand chiral nanoclusters

    OpenAIRE

    Güven, Zekiye Pelin; Guven, Zekiye Pelin; Üstbaş, Burçin; Ustbas, Burcin; Harkness, Kellen M.; Coşkun, Hikmet; Coskun, Hikmet; Joshi, Chakra P.; Besong, Tabot M. D.; Stellacci, Francesco; Bakr, Osman M.; Akbulut, Özge; Akbulut, Ozge

    2015-01-01

    Chiral mixed ligand silver nanoclusters were synthesized in the presence of a chiral and an achiral ligand. The ratio of the ligands was changed to track the formation of these clusters. While the chiral ligand lead to nanoparticles, Presence of the achiral ligand induced the formation of nanoclusters with chiral properties.

  14. Chiral Symmetry Breaking and Cooling in Lattice QCD

    OpenAIRE

    Woloshyn, R. M.; Lee, F. X.

    1995-01-01

    Chiral symmetry breaking is calculated as a function of cooling in quenched lattice QCD. A non-zero signal is found for the chiral condensate beyond one hundred cooling steps, suggesting that there is chiral symmetry breaking associated with instantons. Quantitatively, the chiral condensate in cooled gauge field configurations is small compared to the value without cooling.

  15. Chlorophylls, Symmetry, Chirality, and Photosynthesis

    Directory of Open Access Journals (Sweden)

    Mathias O. Senge

    2014-09-01

    Full Text Available Chlorophylls are a fundamental class of tetrapyrroles and function as the central reaction center, accessory and photoprotective pigments in photosynthesis. Their unique individual photochemical properties are a consequence of the tetrapyrrole macrocycle, the structural chemistry and coordination behavior of the phytochlorin system, and specific substituent pattern. They achieve their full potential in solar energy conversion by working in concert in highly complex, supramolecular structures such as the reaction centers and light-harvesting complexes of photobiology. The biochemical function of these structures depends on the controlled interplay of structural and functional principles of the apoprotein and pigment cofactors. Chlorophylls and bacteriochlorophylls are optically active molecules with several chiral centers, which are necessary for their natural biological function and the assembly of their supramolecular complexes. However, in many cases the exact role of chromophore stereochemistry in the biological context is unknown. This review gives an overview of chlorophyll research in terms of basic function, biosynthesis and their functional and structural role in photosynthesis. It highlights aspects of chirality and symmetry of chlorophylls to elicit further interest in their role in nature.

  16. Chiral sine-Gordon model

    Science.gov (United States)

    Yanagisawa, Takashi

    2016-02-01

    We investigate the chiral sine-Gordon model using the renormalization group method. The chiral sine-Gordon model is a model for G-valued fields and describes a new class of phase transitions, where G is a compact Lie group. We show that the model is renormalizable by means of a perturbation expansion and we derive beta functions of the renormalization group theory. The coefficients of beta functions are represented by the Casimir invariants. The model contains both asymptotically free and ultraviolet strong-coupling regions. The beta functions have a zero which is a bifurcation point that divides the parameter space into two regions; they are the weak-coupling region and the strong-coupling region. A large-N model is also considered. This model is reduced to the conventional sine-Gordon model that describes the Kosterlitz-Thouless transition near the fixed point. In the strong-coupling limit, the model is reduced to a U(N) matrix model.

  17. On the early chiral unification

    International Nuclear Information System (INIS)

    A unified model of electromagnetic, strong and weak interactions based on the semisimple gauge group G=SU(8)sub(L)xSU(8)sub(R) is presented. Leptons and fractionally charged quarks are asigned to fundamental representations Fsub(L)=(usub(i)dsub(i)νsub(e)e)sub(L), Fsub(R)(usub(i)dsub(i)νsub(e)e)sub(R) and similarly for the other families. The model leads to low unification mass M=106-108 GeV and admissible value for the Weinberg parameter sin2THETAsub(W)=1/3. The model contains chiral colour group SU(3)sub(L)xSU(3)sub(R) and permits the existence of light axial gluons (msub(A) approximately 1 GeV) alongside with the massless vector gluons. The barion number is conserved in the model. Triangular anomalies are absent when mirror fermions of opposite chirality are added. The model admits the hierarchy of symmetry breaking and presence of intermediate scales Msub(n) so that Msub(W)<< Msub(n)<< M. In the low energy region the results of Salam-Weinberg model are reproduced

  18. Chiral sine-Gordon model

    CERN Document Server

    Yanagisawa, Takashi

    2016-01-01

    We investigate the chiral sine-Gordon model using the renormalization group method. The chiral sine-Gordon model is a model for $G$-valued fields and describes a new class of phase transitions, where $G$ is a compact Lie group. We show that the model is renormalizable by means of a perturbation expansion and we derive beta functions of the renormalization group theory. The coefficients of beta functions are represented by the Casimir invariants. The model contains both asymptotically free and ultraviolet strong coupling regions. The beta functions have a zero which is a bifurcation point that divides the parameter space into two regions; they are the weak coupling region and the strong coupling region. A large-$N$ model is also considered. This model is reduced to the conventional sine-Gordon model that describes the Kosterlitz-Thouless transition near the fixed point. In the strong-coupling limit, the model is reduced to a $U(N)$ matrix model.

  19. Chiral transition with magnetic fields

    CERN Document Server

    Ayala, Alejandro; Mizher, Ana Julia; Rojas, Juan Cristobal; Villavicencio, Cristian

    2014-01-01

    We study the nature of the chiral transition for an effective theory with spontaneous breaking of symmetry, where charged bosons and fermions are subject to the effects of a constant external magnetic field. The problem is studied in terms of the relative intensity of the magnetic field with respect to the mass and the temperature. When the former is the smallest of the scales, we present a suitable method to obtain magnetic and thermal corrections up to ring order at high temperature. By these means, we solve the problem of the instability in the boson sector for these theories, where the squared masses, taken as functions of the order parameter, can vanish and even become negative. The solution is found by considering the screening properties of the plasma, encoded in the resummation of the ring diagrams at high temperature. We also study the case where the magnetic field is the intermediate of the three scales and explore the nature of the chiral transition as we vary the field strength, the coupling const...

  20. Atroposelective Synthesis of Axially Chiral Thiohydantoin Derivatives.

    Science.gov (United States)

    Sarigul, Sevgi; Dogan, Ilknur

    2016-07-15

    Nonracemic axially chiral thiohydantoins were synthesized atroposelectively by the reaction of o-aryl isothiocyanates with amino acid ester salts in the presence of triethylamine (TEA). The synthesis of the nonaxially chiral derivatives, however, gave thiohydantoins racemized at C-5 of the heterocyclic ring. The micropreparatively resolved enantiomers of the nonaxially chiral derivatives from the racemic products were found to be optically stable under neutral conditions. On formation of the 5-methyl-3-arylthiohydantoin ring, bulky o-aryl substituents at N3 were found to suppress the C-5 racemization and in this way enabled the transfer of chirality from the α-amino acid to the products. The corresponding 5-isopropylthiohydantoins turned out to be more prone to racemization at C-5 during the ring formation. The isomer compositions of the synthesized axially chiral thiohydantoins have been determined through HPLC analyses with chiral stationary phases. In most cases a high prevalence of the P isomers over the M isomers has been obtained. The barriers to rotation determined around the Nsp(2)-Caryl chiral axis were found to be dependent upon the size of the o-halo aryl substituents. PMID:27322739

  1. Chiral polarization scale of QCD vacuum and spontaneous chiral symmetry breaking

    International Nuclear Information System (INIS)

    It has recently been found that dynamics of pure glue QCD supports the low energy band of Dirac modes with local chiral properties qualitatively different from that of a bulk: while bulk modes suppress chirality relative to statistical independence between left and right, the band modes enhance it. The width of such chirally polarized zone – chiral polarization scale bigwedgech – has been shown to be finite in the continuum limit at fixed physical volume. Here we present evidence that bigwedgech remains non-zero also in the infinite volume, and is therefore a dynamical scale in the theory. Our experiments in Nf = 2+1 QCD support the proposition that the same holds in the massless limit, connecting bigwedgech to spontaneous chiral symmetry breaking. In addition, our results suggest that thermal agitation in quenched QCD destroys both chiral polarization and condensation of Dirac modes at the same temperature Tch > Tc.

  2. Dirac operator normality and chiral properties

    International Nuclear Information System (INIS)

    Normality and γ5-hermiticity are what gives rise to chiral properties and rules. The Ginsparg-Wilson (GW) relation is only one of the possible spectral constraints. The sum rule for chiral differences of real modes has important consequences. The alternative transformation of Luescher gives the same Ward identity as the usual chiral one (if zero modes are properly treated). Imposing normality on a general function of the hermitean Wilson-Dirac operator H leads at same time to the GW relation and to the Neuberger operator

  3. Enhanced Chiral Recognition by Cyclodextrin Dimers

    Directory of Open Access Journals (Sweden)

    Bart Jan Ravoo

    2011-07-01

    Full Text Available In this article we investigate the effect of multivalency in chiral recognition. To this end, we measured the host-guest interaction of a β-cyclodextrin dimer with divalent chiral guests. We report the synthesis of carbohydrate-based water soluble chiral guests functionalized with two borneol, menthol, or isopinocampheol units in either (+ or (– configuration. We determined the interaction of these divalent guests with a β-cyclodextrin dimer using isothermal titration calorimetry. It was found that—in spite of a highly unfavorable conformation—the cyclodextrin dimer binds to guest dimers with an increased enantioselectivity, which clearly reflects the effect of multivalency.

  4. Effective action in general chiral superfield model

    OpenAIRE

    Petrov, A. Yu.

    2000-01-01

    The effective action in general chiral superfield model with arbitrary k\\"{a}hlerian potential $K(\\bar{\\Phi},\\Phi)$ and chiral (holomorphic) potential $W(\\Phi)$ is considered. The one-loop and two-loop contributions to k\\"{a}hlerian effective potential and two-loop (first non-zero) contribution to chiral effective potential are found for arbitrary form of functions $K(\\bar{\\Phi},\\Phi)$ and $W(\\Phi)$. It is found that despite the theory is non-renormalizable in general case two-loop contributi...

  5. Dynamics and Stability of Chiral Fluid

    OpenAIRE

    Mishustin, Igor N.; Koide, Tomoi; Denicol, Gabriel S.; Torrieri, Giorgio

    2014-01-01

    Starting from the linear sigma model with constituent quarks we derive the chiral fluid dynamics where hydrodynamic equations for the quark fluid are coupled to the equation of motion for the order-parameter field. In a static system at thermal equilibrium this model leads to a chiral phase transition which, depending on the choice of the quark-meson coupling constant, could be a crossover or a first order one. We investigate the stability of the chiral fluid in the static and expanding backg...

  6. The Macromolecular Route to Chiral Amplification.

    Science.gov (United States)

    Green; Park; Sato; Teramoto; Lifson; Selinger; Selinger

    1999-11-01

    Cooperative phenomena, described by one-dimensional statistical physical methods, are observed between the enantiomeric characteristics of monomeric materials and the polymers they produce. The effect of minute energies associated with this amplified chirality, although currently not interpretable, can be easily measured. Nonlinear relationships between enantiomeric excess or enantiomeric content and polymer properties may offer the possibility of developing chiral catalysts and chiral chromatographic materials in which the burden of large enantiomeric excess or content may be considerably alleviated. New approaches to information and sensor technology may become possible. PMID:10556885

  7. Chiral particle separation by a non-chiral micro-lattice

    OpenAIRE

    Bogunovic, Lukas; Fliedner, Marc; Eichhorn, Ralf; Wegener, Sonja; Regtmeier, Jan; Anselmetti, Dario; Reimann, Peter

    2012-01-01

    We conceived a model experiment for a continuous separation strategy of chiral molecules (enantiomers) without the need of any chiral selector structure or derivatization agents: Micro-particles that only differ by their chirality are shown to migrate along different directions when driven by a steady fluid flow through a square lattice of cylindrical posts. In accordance with our numerical predictions, the transport directions of the enantiomers depend very sensitively on the orientation of ...

  8. Double chiral logarithms of Generalized Chiral Perturbation Theory for low-energy pi-pi scattering

    OpenAIRE

    L. GirlandaPadua U. & INFN

    2015-01-01

    We express the two-massless-flavor Gell-Mann--Oakes--Renner ratio in terms of low-energy pi-pi observables, including the O(p^6) double chiral logarithms of generalized chiral perturbation theory. Their contribution is sizeable and tends to compensate the one from the single chiral logarithms. However it is not large enough to spoil the convergence of the chiral expansion. As a signal of reduced theoretical uncertainty, we find that the scale dependence from the one-loop single logarithms is ...

  9. New Chiral Metal Cluster Systems for Catalytic Asymmetric Syntheses of Chiral Alcohols

    Institute of Scientific and Technical Information of China (English)

    LI Yan-yun; CHEN Jian-shan; YANG Chuan-bo; DONG Zhen-rong; LI Bao-zhu; ZHANG Hui; GAO Jing-xing; TAKAO Ikariya

    2004-01-01

    The efficient chiral Ru3(CO)12 systems were prepared in situ from Ru3(CO)12 and various chiral diiminoor diamino-diphosphine tetradentate ligands. The systems have been used for the asymmetric transfer hydrogenation of propiophenone in 2-propanol, leading to 1-phenyl-1-propanol in a 98% yield and 96% e.e. The IR study suggests that the carbonyl hydride anion [HRu3(CO)11]- most probably exists as a principal species under the reaction conditions. The high chiral efficiency may be due to the synergetic effect produced by the neighboring ruthenium atoms and a special chiral micro-environment involving the polydentate ligand and the Ru3 framework.

  10. Chiral magnetic effect and holography

    International Nuclear Information System (INIS)

    The chiral magnetic effect (CME) is a highly discussed effect in heavy-ion collisions stating that, in the presence of a magnetic field B, an electric current is generated in the background of topologically nontrivial gluon fields. We present a holographic (AdS/CFT) description of the CME in terms of a fluid-gravity model which is dual to a strongly-coupled plasma with multiple anomalous U(1) currents. In the case of two U(1) charges, one axial and one vector, the CME formally appears as a first-order transport coefficient in the vector current. We will holographically compute this coefficient at strong coupling and compare it with the hydrodynamic result. Finally, we will discuss an anisotropic variant of the model and study a possible dependence of the CME on the elliptic flow coefficient ν2.

  11. Resolution of the Chiral Drugs

    Institute of Scientific and Technical Information of China (English)

    DENG JinGen; ZHU Jin

    2001-01-01

    @@ Chiral drugs are generally not permitted to be used in racemic form so that unintended side effects and unnecessary environmental hazards are avoided. Moreover, homochiral molecules are required immediately to progress key toxicological and clinical studies in the drug discovery. One series of technologies which can rapidly supply homochiral compounds is the separation of racemates, and of those the technique of crystallization of diastereomers is extremely effective-principally because it is simple to operate and it affords both enantiomers. In classical resolution via diastereoisomeric salt formation, the resolved compounds are limited to a given racemic acid or base and the choice of a suitable resolving agent for a racemic target compound is achieved by time-consuming trial-and-error procedure.

  12. Resolution of the Chiral Drugs

    Institute of Scientific and Technical Information of China (English)

    DENG; JinGen

    2001-01-01

    Chiral drugs are generally not permitted to be used in racemic form so that unintended side effects and unnecessary environmental hazards are avoided. Moreover, homochiral molecules are required immediately to progress key toxicological and clinical studies in the drug discovery. One series of technologies which can rapidly supply homochiral compounds is the separation of racemates, and of those the technique of crystallization of diastereomers is extremely effective-principally because it is simple to operate and it affords both enantiomers. In classical resolution via diastereoisomeric salt formation, the resolved compounds are limited to a given racemic acid or base and the choice of a suitable resolving agent for a racemic target compound is achieved by time-consuming trial-and-error procedure.  ……

  13. Chiral supergravity actions and superforms

    CERN Document Server

    Gates, S J; Tartaglino-Mazzucchelli, G

    2009-01-01

    The superform construction of supergravity actions, christened the "ectoplasm method," is based on the use of a closed super d-form in the case of d space-time dimensions. In known examples, such superforms are obtained by iteratively solving nontrivial cohomological problems. The latter usually makes this scheme no less laborious than the normal coordinate method for deriving component actions for matter-coupled supergravity. In this note we present an alternative procedure to generate required superforms in four space-time dimensions, which makes use of self-dual vector multiplets. It provides the shortest derivation of chiral actions in two different theories: (i) N = 1 old minimal supergravity; and (ii) N = 2 conformal supergravity. The N = 2 superform construction is developed here for the first time. Although our consideration is restricted to the case of four dimensions, a generalization to higher dimensions is plausible.

  14. Chiral magnetic effect and holography

    Energy Technology Data Exchange (ETDEWEB)

    Kirsch, Ingo; Kalaydzhyan, Tigran

    2013-01-15

    The chiral magnetic effect (CME) is a highly discussed effect in heavy-ion collisions stating that, in the presence of a magnetic field B, an electric current is generated in the background of topologically nontrivial gluon fields. We present a holographic (AdS/CFT) description of the CME in terms of a fluid-gravity model which is dual to a strongly-coupled plasma with multiple anomalous U(1) currents. In the case of two U(1) charges, one axial and one vector, the CME formally appears as a first-order transport coefficient in the vector current. We will holographically compute this coefficient at strong coupling and compare it with the hydrodynamic result. Finally, we will discuss an anisotropic variant of the model and study a possible dependence of the CME on the elliptic flow coefficient {nu}{sub 2}.

  15. Chiral Lagrangians and proton decay

    International Nuclear Information System (INIS)

    The phenomenological Lagrangian method is employed to obtain nucleon decay branching ratio sin conventional and supersymmetric Grand Unified Theories. After a brief survey of the theory of nucleon decay, the dominant effective baryon-number violating operators in supergravity models are derived where the observed sector is described by an SU(5) SUSY GUT. It is shown how the phenomenological Lagrangian technique may be understood from a mathematical viewpoint. This technique is then applied to calculate two- and three-body nucleon decay branching ratios in SUGRA models. Finally, the author answers criticism of the usual phenomenological Lagrangian approach when used for nucleon decay calculations by developing a hybrid chiral quark model. With this model, branching ratios for conventional and SUSY GUTs are calculated. (author)

  16. Binary mixtures of chiral gases

    CERN Document Server

    Presilla, Carlo

    2015-01-01

    A possible solution of the well known paradox of chiral molecules is based on the idea of spontaneous symmetry breaking. At low pressure the molecules are delocalized between the two minima of a given molecular potential while at higher pressure they become localized in one minimum due to the intermolecular dipole-dipole interactions. Evidence for such a phase transition is provided by measurements of the inversion spectrum of ammonia and deuterated ammonia at different pressures. In particular, at pressure greater than a critical value no inversion line is observed. These data are well accounted for by a model previously developed and recently extended to mixtures. In the present paper, we discuss the variation of the critical pressure in binary mixtures as a function of the fractions of the constituents.

  17. Biaxiality of chiral liquid crystals

    International Nuclear Information System (INIS)

    Using extended deGennes-Ginzburg-Landau free energy expansion in terms of the anisotropic part of the dielectric tensor field Qαβ(χ) a connection between the phase biaxiality and the stability of various chiral liquid crystalline phases is studied. In particular the cholesteric phase, the cubic Blue Phases and the phases characterized by an icosahedral space group symmetry are analysed in detail. Also a general question concerning the applicability of the mean-field approximation in describing the chiral phases is addressed. By an extensive study of the model over a wide range of the parameters a new class of phenomena, not present in the original deGennes-Ginzburg-Landau model, has been found. These include: a) re-entrant phase transitions between the cholesteric and the cubic blue phases and b) the existence of distinct phases of the same symmetry but of different biaxialities. The phase biaxiality serves here as an extra scalar order parameter. Furthermore, it has been shown that due to the presence of the competing bulk terms in the free energy, the stable phases may acquire a large degree of biaxiality, also in liquid crystalline materials composed of effectively uniaxial molecules. A study of icosahedral space group symmetries gives a partial answer to the question as to whether an icosahedral quasicrystalline liquid could be stabilized in liquid crystals. Although, in general, the stability of icosahedral structures could be enhanced by the extra terms in the free energy no absolutely stable icosahedral phase has been found. (author). 16 refs, 3 figs, 1 tab

  18. Chiral Schwinger model at finite temperature

    International Nuclear Information System (INIS)

    We discuss the chiral Schwinger model at finite temperature using Fujikawa's method. We solve this model exactly and show that the axial anomaly and the dynamically generated mass for the gauge field are temperature independent. (author). 20 refs

  19. Chiral transition of fundamental and adjoint quarks

    Energy Technology Data Exchange (ETDEWEB)

    Capdevilla, R.M. [Instituto de Física Teórica, UNESP – Universidade Estadual Paulista, Rua Dr. Bento T. Ferraz, 271, Bloco II, 01140-070 São Paulo, SP (Brazil); Doff, A., E-mail: agomes@utfpr.edu.br [Universidade Tecnológica Federal do Paraná – UTFPR – DAFIS, Av. Monteiro Lobato Km 04, 84016-210 Ponta Grossa, PR (Brazil); Natale, A.A., E-mail: natale@ift.unesp.br [Instituto de Física Teórica, UNESP – Universidade Estadual Paulista, Rua Dr. Bento T. Ferraz, 271, Bloco II, 01140-070 São Paulo, SP (Brazil); Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, 09210-170 Santo André, SP (Brazil)

    2014-01-20

    The chiral symmetry breaking transition of quarks in the fundamental and adjoint representation is studied in a model where the gap equation contains two contributions, one containing a confining propagator and another corresponding to the exchange of one-dressed dynamically massive gluons. When quarks are in the fundamental representation the confinement effect dominates the chiral symmetry breaking while the gluon exchange is suppressed due to the dynamical gluon mass effect in the propagator and in the coupling constant. In this case the chiral and deconfinement transition temperatures are approximately the same. For quarks in the adjoint representation, due to the larger Casimir eigenvalue, the gluon exchange is operative and the chiral transition happens at a larger temperature than the deconfinement one.

  20. Chiral transition of fundamental and adjoint quarks

    International Nuclear Information System (INIS)

    The chiral symmetry breaking transition of quarks in the fundamental and adjoint representation is studied in a model where the gap equation contains two contributions, one containing a confining propagator and another corresponding to the exchange of one-dressed dynamically massive gluons. When quarks are in the fundamental representation the confinement effect dominates the chiral symmetry breaking while the gluon exchange is suppressed due to the dynamical gluon mass effect in the propagator and in the coupling constant. In this case the chiral and deconfinement transition temperatures are approximately the same. For quarks in the adjoint representation, due to the larger Casimir eigenvalue, the gluon exchange is operative and the chiral transition happens at a larger temperature than the deconfinement one

  1. Personal recollections on chiral symmetry breaking

    Science.gov (United States)

    Kobayashi, Makoto

    2016-07-01

    The author's work on the mass of pseudoscalar mesons is briefly reviewed. The emergence of the study of CP violation in the renormalizable gauge theory from consideration of chiral symmetry in the quark model is discussed.

  2. Chirality and angular momentum in optical radiation

    CERN Document Server

    Coles, Matt M

    2012-01-01

    This paper develops, in precise quantum electrodynamic terms, photonic attributes of the "optical chirality density", one of several measures long known to be conserved quantities for a vacuum electromagnetic field. The analysis lends insights into some recent interpretations of chiroptical experiments, in which this measure, and an associated chirality flux, have been treated as representing physically distinctive "superchiral" phenomena. In the fully quantized formalism the chirality density is promoted to operator status, whose exploration with reference to an arbitrary polarization basis reveals relationships to optical angular momentum and helicity operators. Analyzing multi-mode beams with complex wave-front structures, notably Laguerre-Gaussian modes, affords a deeper understanding of the interplay between optical chirality and optical angular momentum. By developing theory with due cognizance of the photonic character of light, it emerges that only the spin angular momentum of light is engaged in such...

  3. Parity doublers in chiral potential quark models

    International Nuclear Information System (INIS)

    The effect of spontaneous breaking of chiral symmetry over the spectrum of highly excited hadrons is addressed in the framework of a microscopic chiral potential quark model (Generalised Nambu-Jona-Lasinio model) with a vectorial instantaneous quark kernel of a generic form. A heavy-light quark-antiquark bound system is considered, as an example, and the Lorentz nature of the effective light-quark potential is identified to be a pure Lorentz-scalar, for low-lying states in the spectrum, and to become a pure spatial Lorentz vector, for highly excited states. Consequently, the splitting between the partners in chiral doublets is demonstrated to decrease fast in the upper part of the spectrum so that neighboring states of an opposite parity become almost degenerate. A detailed microscopic picture of such a 'chiral symmetry restoration' in the spectrum of highly excited hadrons is drawn and the corresponding scale of restoration is estimated

  4. Staggered Heavy Baryon Chiral Perturbation Theory

    CERN Document Server

    Bailey, Jon A

    2007-01-01

    Although taste violations significantly affect the results of staggered calculations of pseudoscalar and heavy-light mesonic quantities, those entering staggered calculations of baryonic quantities have not been quantified. Here I develop staggered chiral perturbation theory in the light-quark baryon sector by mapping the Symanzik action into heavy baryon chiral perturbation theory. For 2+1 dynamical quark flavors, the masses of flavor-symmetric nucleons are calculated to third order in partially quenched and fully dynamical staggered chiral perturbation theory. To this order the expansion includes the leading chiral logarithms, which come from loops with virtual decuplet-like states, as well as terms the order of the cubed pion mass, which come from loops with virtual octet-like states. Taste violations enter through the meson propagators in loops and tree-level terms the order of the squared lattice spacing. The pattern of taste symmetry breaking and the resulting degeneracies and mixings are discussed in d...

  5. BRST Reduction of the chiral Hecke Algebra

    OpenAIRE

    Shapiro, I

    2006-01-01

    We explore the relationship between de Rham and Lie algebra cohomologies in the finite dimensional and affine settings. As an application, we describe the BRST reduction of the chiral Hecke algebra as a vertex super algebra.

  6. Chiral chemistry of metal-camphorate frameworks.

    Science.gov (United States)

    Gu, Zhi-Gang; Zhan, Caihong; Zhang, Jian; Bu, Xianhui

    2016-06-01

    This critical review presents the various synthetic approaches and chiral chemistry of metal-camphorate frameworks (MCamFs), which are homochiral metal-organic frameworks (MOFs) constructed from a camphorate ligand. The interest in this unique subset of homochiral MOFs is derived from the many interesting chiral features for both materials and life sciences, such as asymmetrical synthesis or crystallization, homochiral structural design, chiral induction, absolute helical control and ligand handedness. Additionally, we discuss the potential applications of homochiral MCamFs. This review will be of interest to researchers attempting to design other homochiral MOFs and those engaged in the extension of MOFs for applications such as chiral recognition, enantiomer separation, asymmetric catalysis, nonlinear sensors and devices. PMID:27021070

  7. Nuclear Chiral EFT in the Precision Era

    CERN Document Server

    Epelbaum, Evgeny

    2015-01-01

    Chiral effective field theory has established itself as the method of choice to study nuclear forces and low-energy nuclear dynamics. I review the status and prospects of this approach and discuss ongoing efforts to advance the precision frontier for ab initio description of few-nucleon systems. Special emphasis is put on the precise determination of the two-nucleon force at fifth order in the chiral expansion, role of the chiral symmetry, the convergence pattern of the chiral expansion and the quantification of the theoretical uncertainties. The discussed topics are essential for ongoing studies towards elucidating the structure of the three-nucleon force which will be briefly addressed as well.

  8. Chirally motivated K{sup -} nuclear potentials

    Energy Technology Data Exchange (ETDEWEB)

    Cieply, A. [Nuclear Physics Institute, 25068 Rez (Czech Republic); Friedman, E. [Racah Institute of Physics, Hebrew University, 91904 Jerusalem (Israel); Gal, A., E-mail: avragal@vms.huji.ac.il [Racah Institute of Physics, Hebrew University, 91904 Jerusalem (Israel); Gazda, D.; Mares, J. [Nuclear Physics Institute, 25068 Rez (Czech Republic)

    2011-08-26

    In-medium subthreshold K-bar N scattering amplitudes calculated within a chirally motivated meson-baryon coupled-channel model are used self consistently to confront K{sup -} atom data across the periodic table. Substantially deeper K{sup -} nuclear potentials are obtained compared to the shallow potentials derived in some approaches from threshold K-bar N amplitudes, with ReV{sub K}{sup chiral}=-(85{+-}5) MeV at nuclear matter density. When K-bar NN contributions are incorporated phenomenologically, a very deep K{sup -} nuclear potential results, ReV{sub K}{sup chiral+phen.}=-(180{+-}5) MeV, in agreement with density dependent potentials obtained in purely phenomenological fits to the data. Self consistent dynamical calculations of K{sup -}-nuclear quasibound states generated by V{sub K}{sup chiral} are reported and discussed.

  9. New Advances in Chiral Catalyst Immobilization

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Asymmetric catalysis of organic reactions is one of the most efficient ways to obtain optically pure chiral compounds, which are crucially important to the development of modern pharmaceutical and fine chemical industries, as well as material science.

  10. Chiral Magnetic Effect in Heavy Ion Collisions

    CERN Document Server

    Liao, Jinfeng

    2016-01-01

    The Chiral Magnetic Effect (CME) is a remarkable phenomenon that stems from highly nontrivial interplay of QCD chiral symmetry, axial anomaly, and gluonic topology. It is of fundamental importance to search for the CME in experiments. The heavy ion collisions provide a unique environment where a hot chiral-symmetric quark-gluon plasma is created, gluonic topological fluctuations generate chirality imbalance, and very strong magnetic fields $|\\vec{\\bf B}|\\sim m_\\pi^2$ are present during the early stage of such collisions. Significant efforts have been made to look for CME signals in heavy ion collision experiments. In this contribution we give a brief overview on the status of such efforts.

  11. Insights on some chiral smectic phases

    Indian Academy of Sciences (India)

    B Pansu

    2003-08-01

    Combining layered positional order as smectic order and chirality can generate complex architectures since twist parallel to the layers is not allowed. This paper will review some new experimental results on different phases resulting from the competition between smectic positional order and twist orientational order. It concerns the TGBA and the NL*, that is the liquid line phase as well as the SmQ phase. Chiral effects in the isotropic phase will also be discussed.

  12. Is the chiral U(1) theory trivial?

    International Nuclear Information System (INIS)

    The chiral U(1) theory differs from the corresponding vector theory by an imaginary contribution to the effective action which amounts to a phase factor in the partition function. The vector theory, i.e. QED, is known to be trivial in the continuum limit. It is argued that the presence of the phase factor will not alter this result and the chiral theory is non-interacting as well. (orig.)

  13. Chiral gauge theories on a lattice

    International Nuclear Information System (INIS)

    The authors formulate a chiral gauge invariant theory of lattice fermions by introducing extra degrees of freedom. It is applied to the chiral U(1) gauge theories in two and four dimensions and the effective actions of the gauge fields are calculated which indicate the mass generation of the gauge bosons. The difficulty is pointed out to execute the perturbation with a finite gauge boson mass in four dimensions

  14. Chiral transition of fundamental and adjoint quarks

    OpenAIRE

    Capdevilla, R. M.; Doff, A.(Universidade Tecnológica Federal do Paraná – UTFPR – DAFIS, Av. Monteiro Lobato Km 04, 84016-210 Ponta Grossa, PR, Brazil); Natale, A. A.

    2014-01-01

    The chiral symmetry breaking transition of quarks in the fundamental and adjoint representation is studied in a model where the gap equation contains two contributions, one containing a confining propagator and another corresponding to the exchange of one-dressed dynamically massive gluons. When quarks are in the fundamental representation the confinement effect dominates the chiral symmetry breaking while the gluon exchange is suppressed due to the dynamical gluon mass effect in the propagat...

  15. Super Virasoro Algebras From Chiral Supergravity

    CERN Document Server

    Hyakutake, Yoshifumi

    2015-01-01

    In this note, we construct Noether charges for the chiral supergravity, which contains the Lorentz Chern-Simons term, by applying Wald's prescription to the vielbein formalism. We investigate the AdS3/CFT2 correspondence by using the vielbein formalism. The asymptotic symmetry group is carefully examined by taking into account the local Lorentz transformation, and we construct super Virasoro algebras with central extensions from the chiral supergravity.

  16. Chiral effective model with the Polyakov loop

    OpenAIRE

    Fukushima, Kenji

    2003-01-01

    We discuss how the simultaneous crossovers of deconfinement and chiral restoration can be realized. We propose a dynamical mechanism assuming that the effective potential gives a finite value of the chiral condensate if the Polyakov loop vanishes. Using a simple model, we demonstrate that our idea works well for small quark mass, though there should be further constraints to reach the perfect locking of two phenomena.

  17. Unphysical phases in staggered chiral perturbation theory

    Science.gov (United States)

    Aubin, Christopher; Colletti, Katrina; Davila, George

    2016-04-01

    We study the phase diagram for staggered quarks using chiral perturbation theory. In beyond-the-standard-model simulations using a large number (>8 ) of staggered fermions, unphysical phases appear for coarse enough lattice spacing. We argue that chiral perturbation theory can be used to interpret one of these phases. In addition, we show that only three broken phases for staggered quarks exist, at least for lattice spacings in the regime a2≪ΛQCD2 .

  18. Attomolar DNA detection with chiral nanorod assemblies

    OpenAIRE

    Ma, Wei; Kuang, Hua; Xu, Liguang; Ding, Li; Xu, Chuanlai; Wang, Libing; Kotov, Nicholas A.

    2013-01-01

    Nanoscale plasmonic assemblies display exceptionally strong chiral optical activity. So far, their structural design was primarily driven by challenges related to metamaterials whose practical applications are remote. Here we demonstrate that gold nanorods assembled by the polymerase chain reaction into DNA-bridged chiral systems have promising analytical applications. The chiroplasmonic activity of side-by-side assembled patterns is attributed to a 7–9 degree twist between the nanorod axes. ...

  19. Chiral quantum mechanics (CQM) for antihydrogen systems

    OpenAIRE

    Van hooydonk, G.

    2005-01-01

    A first deception of QM on antiH already appears in one-center integrals for two-center systems (G. Van Hooydonk, physics/0511115). In reality, full QM is a theory for chiral systems but the QM establishment was wrong footed with a permutation of reference frames. With chiral quantum mechanics (CQM), the theoretical ban on natural antiH must be lifted as soon as possible.

  20. Chiral Symmetry in algebraic and analytic approaches

    OpenAIRE

    Vereshagin, V.; Dillig, M.; Vereshagin, A.

    1996-01-01

    We compare among themselves two different methods for the derivation of results following from the requirement of polynomial boundedness of tree-level chiral amplitudes. It is shown that the results of the algebraic approach are valid also in the framework of the analytical one. This means that the system of Sum Rules and Bootstrap equations previously obtained with the help of the latter approach can be analyzed in terms of reducible representations of the unbroken Chiral group with the know...

  1. Chiral bags, skyrmions and quarks in nuclei

    International Nuclear Information System (INIS)

    Recent developments on an intriguing connection between the quark-bag description of the baryons (nucleons in particular) and the Skyrmion model are discussed in terms of the constraints coming from chiral anomalies. Topics treated are the leaking baryon charge, axial charge and energy density; the role of chiral anomalies; the role of Skyrme's quartic term and the connection to the meson degrees of freedom; and finally some qualitative implications in nuclei. The presentation is purposely descriptive and intuitive instead of mathematically precise

  2. Center vortices, confinement and chiral symmetry breaking

    International Nuclear Information System (INIS)

    The center vortex model, proposed as an explanation of confinement in non-abelian gauge theories is introduced. Some checks of the confinement properties of center vortices in SU(2) lattice gauge theory with improved Luescher-Weisz gauge action are presented. Phenomena related to chiral symmetry, such as topological charge and spontaneous chiral symmetry breaking (SCSB) are studied within the vortex model. In particular the influence of center vortices on the low-lying spectrum of the Dirac operator is analyzed. (author)

  3. Nondipole Photoemission from Chiral Enantiomers of Camphor

    Science.gov (United States)

    Bowen, K. P.; Stolte, W. C.; Young, J. A.; Demchenko, I. N.; Guillemin, R.; Hemmers, O.; Piancastelli, M. N.; Lindle, D. W.

    2010-03-01

    K-shell photoemission from the carbonyl carbon in the chiral molecule camphor has been studied in the region just above the core-shell ionization threshold. Differences between angular distributions of emitted photoelectrons from the two enantiomers are attributed to the influence of chirality combined with nondipole effects in the photoemission process, despite the fact the measurements were taken using linearly polarized x-rays. The results suggest the possibility of a new form of linear dichroism.

  4. Probing molecular chirality via electronic transport

    International Nuclear Information System (INIS)

    We investigate electronic molecular transport in several conjugated organic oligomers by means of ab initio calculations and nonequilibrium Green's functions method. We demonstrate that the I-V characteristics of these molecules constitute a direct manifestation of their degree of molecular chirality, which is calculated using group theory and depends exclusively on the atomic positions. This result shows that electronic current through these specific molecules is strongly correlated with their geometrical degree of chirality.

  5. Tests of Chiral Perturbation Theory with COMPASS

    CERN Document Server

    Friedrich, Jan

    2010-01-01

    The COMPASS experiment at the CERN SPS studies with high precision pion-photon induced reactions via the Primakoff effect on nuclear targets. This offers the test of chiral perturbation theory (ChPT) in various channels: Pion Compton scattering allows to clarify the long-standing question of the pion polarisabilities, single neutral pion production is related to the chiral anomaly, and for the two-pion production cross sections exist as yet untested ChPT predictions.

  6. Tests of Chiral Perturbation Theory with COMPASS

    International Nuclear Information System (INIS)

    The COMPASS experiment at CERN studies with high precision pion-photon induced reactions on nuclear targets via the Primakoff effect. This offers the possibility to test chiral perturbation theory (ChPT) in various channels: Pion Compton scattering allows to clarify the longstanding question of the pion polarisabilities, single neutral pion production is related to the chiral anomaly, and for the two-pion production cross sections exist as yet untested ChPT predictions.

  7. A Cross-chiral RNA Polymerase Ribozyme

    OpenAIRE

    Sczepanski, Jonathan T.; Joyce, Gerald F.

    2014-01-01

    Thirty years ago it was shown that the non-enzymatic, template-directed polymerization of activated mononucleotides proceeds readily in a homochiral system, but is severely inhibited by the presence of the opposing enantiomer. 1 This finding poses a severe challenge for the spontaneous emergence of RNA-based life, and has led to the suggestion that either RNA was preceded by some other genetic polymer that is not subject to chiral inhibition 2 or chiral symmetry was broken through chemical pr...

  8. Interfacial energies of systems of chiral molecules

    OpenAIRE

    Braides, Andrea; Garroni, Andrea; Palombaro, Mariapia

    2016-01-01

    We consider a simple model for the assembly of chiral molecules in two dimensions driven by maximization of the contact area. We derive a macroscopic model described by a parameter taking nine possible values corresponding to the possible minimal microscopic patterns and modulated phases of the chiral molecules. We describe the overall behaviour by means of an interaction energy of perimeter type between such phases. This energy is a crystalline perimeter energy, highlighting preferred direct...

  9. Proton Spin Based On Chiral Dynamics

    OpenAIRE

    Weber, H. J.

    1999-01-01

    Chiral spin fraction models agree with the proton spin data only when the chiral quark-Goldstone boson couplings are pure spinflip. For axial-vector coupling from soft-pion physics this is true for massless quarks but not for constituent quarks. Axial-vector quark-Goldstone boson couplings with {\\bf constituent} quarks are found to be inconsistent with the proton spin data.

  10. Lattice quantum chromodynamics with approximately chiral fermions

    Energy Technology Data Exchange (ETDEWEB)

    Hierl, Dieter

    2008-05-15

    In this work we present Lattice QCD results obtained by approximately chiral fermions. We use the CI fermions in the quenched approximation to investigate the excited baryon spectrum and to search for the {theta}{sup +} pentaquark on the lattice. Furthermore we developed an algorithm for dynamical simulations using the FP action. Using FP fermions we calculate some LECs of chiral perturbation theory applying the epsilon expansion. (orig.)

  11. Lattice quantum chromodynamics with approximately chiral fermions

    International Nuclear Information System (INIS)

    In this work we present Lattice QCD results obtained by approximately chiral fermions. We use the CI fermions in the quenched approximation to investigate the excited baryon spectrum and to search for the Θ+ pentaquark on the lattice. Furthermore we developed an algorithm for dynamical simulations using the FP action. Using FP fermions we calculate some LECs of chiral perturbation theory applying the epsilon expansion. (orig.)

  12. Chiral symmetry and lattice gauge theory

    International Nuclear Information System (INIS)

    I review the problem of formulating chiral symmetry in lattice gauge theory. I discuss recent approaches involving an infinite tower of additional heavy states to absorb Fermion doublers. For hadronic physics this provides a natural scheme for taking quark masses to zero without requiring a precise tuning of parameters. A mirror Fermion variation provides a possible way of extending the picture to chirally coupled light Fermions

  13. Large Enhancement of Circular Dichroism Using an Embossed Chiral Metamaterial

    CERN Document Server

    Mousavi, S Hamed Shams; El-Sayed, Mostafa A; Eftekhar, Ali A; Adibi, Ali

    2016-01-01

    In the close vicinity of a chiral nanostructure, the circular dichroism of a biomolecule could be greatly enhanced, due to the interaction with the local superchiral fields. Modest enhancement of optical activity using a planar metamaterial, with some chiral properties, and achiral nanoparticles has been previously reported. A more substantial chirality enhancement can be achieved in the local filed of a chiral nanostructure with a three-dimensional arrangement. Using an embossed chiral nanostructure designed for chiroptical sensing, we measure the circular dichroism spectra of two biomolecules, Chlorophylls A and B, at the molecular level, using a simple polarization resolved reflection measurement. This experiment is the first realization of the on-resonance surface-enhanced circular dichroism, achieved by matching the chiral resonances of a strongly chiral metamaterial with that of a chiral molecule, resulting in an unprecedentedly large differential CD spectrum from a monolayer of a chiral material.

  14. Analysis of rainbow scattering by a chiral sphere.

    Science.gov (United States)

    Shang, Qing-Chao; Wu, Zhen-Sen; Qu, Tan; Li, Zheng-Jun; Bai, Lu; Gong, Lei

    2013-09-23

    Based on the scattering theory of a chiral sphere, rainbow phenomenon of a chiral sphere is numerically analyzed in this paper. For chiral spheres illuminated by a linearly polarized wave, there are three first-order rainbows, with whose rainbow angles varying with the chirality parameter. The spectrum of each rainbow structure is presented and the ripple frequencies are found associated with the size and refractive indices of the chiral sphere. Only two rainbow structures remain when the chiral sphere is illuminated by a circularly polarized plane wave. Finally, the rainbows of chiral spheres with slight chirality parameters are found appearing alternately in E-plane and H-plane with the variation of the chirality. PMID:24104080

  15. Bringing chiral optical forces to dominance with optical nanofibers

    CERN Document Server

    Alizadeh, M H

    2016-01-01

    Transverse spin angular momentum (SAM) of light and associated transverse chiral optical forces have received tremendous attention recently as the latter may lead to an optical separation of chiral biomolecules. Previous schemes to generate chiral forces are plagued by the fact that the chiral optical forces are orders of magnitude smaller than conventional gradient and scattering forces. The relative magnitude of chiral and non-chiral forces represents a fundamental challenge for the implementation of chiral separation schemes. In this work we demonstrate that, by spatially separating the maxima of transverse spin density from the gradient of field intensity, in the vicinity of optical nanofibers and nanowires, chiral optical forces can emerge that are stronger than gradient and scattering forces. This finding has important implications for the design of improved optical separation schemes for chiral biomolecules.

  16. Interplay between chiral and deconfinement phase transitions

    Directory of Open Access Journals (Sweden)

    Mukherjee T.K.

    2011-04-01

    Full Text Available By using the dressed Polyakov loop or dual chiral condensate as an equivalent order parameter of the deconfinement phase transition, we investigate the relation between the chiral and deconfinement phase transitions at finite temperature and density in the framework of three-flavor Nambu-Jona-Lasinio (NJL model. It is found that in the chiral limit, the critical temperature for chiral phase transition coincides with that of the dressed Polyakov loop in the whole (T,µ plane. In the case of explicit chiral symmetry breaking, it is found that the phase transitions are flavor dependent. For each flavor, the transition temperature for chiral restoration $T^{mathcal{X}}_c$ is smaller than that of the dressed Polyakov loop $T^{mathcal{D}}_c$ in the low baryon density region where the transition is a crossover, and, the two critical temperatures coincide in the high baryon density region where the phase transition is of first order. Therefore, there are two critical end points, i.e, $T^{u,d}_{CEP}$ and $T^{s}_{CEP}$ at finite density. We also explain the feature of $T^{mathcal{X}}_c$ = $T^{mathcal{D}}_c$ in the case of 1st and 2nd order phase transitions, and $T^{mathcal{X}}_c$ < $T^{mathcal{D}}_c$ in the case of crossover, and expect this feature is general and can be extended to full QCD theory.

  17. Chiral symmetry restoration in effective Lagrangian models

    International Nuclear Information System (INIS)

    The restoration is studied of chiral symmetry in dense baryon matter using effective lagrangian models of QCD, in which baryons are described as topological solitons. Starting from the breaking of scale invariance and chiral symmetry in the QCD vacuum, the foundations are discussed of effective lagrangians and their relevance for applications to dense matter. Soliton models, such a the Skyrme model, show a phase transition at high densities, whose order parameter is the average scalar field. The properties are investigated of the two phases of the effective theory and show that the phase transition corresponds to the restoration of the chiral symmetry of QCD. It is argued that it should not be understood as deconfinement. The author then considers this phase transition in the context of the Cheshire Cat principle, which provides the link to the underlying quarks of QCD. An analogue of the Cheshire Cat property of this chiral bag model for baryons is found in solitons of effective lagrangians with a scalar glueball field. The Cheshire Cat interpretation of the results of effective lagrangians provides a consistent picture of chiral symmetry restoration at high densities. To verify this interpretation explicitly, the author finally generalizes the effective lagrangian approach to dense matter to a chiral bag model description with quark degrees of freedom

  18. Staggered heavy baryon chiral perturbation theory

    Science.gov (United States)

    Bailey, Jon A.

    2008-03-01

    Although taste violations significantly affect the results of staggered calculations of pseudoscalar and heavy-light mesonic quantities, those entering staggered calculations of baryonic quantities have not been quantified. Here I develop staggered chiral perturbation theory in the light-quark baryon sector by mapping the Symanzik action into heavy baryon chiral perturbation theory. For 2+1 dynamical quark flavors, the masses of flavor-symmetric nucleons are calculated to third order in partially quenched and fully dynamical staggered chiral perturbation theory. To this order the expansion includes the leading chiral logarithms, which come from loops with virtual decuplet-like states, as well as terms of O(mπ3), which come from loops with virtual octet-like states. Taste violations enter through the meson propagators in loops and tree-level terms of O(a2). The pattern of taste symmetry breaking and the resulting degeneracies and mixings are discussed in detail. The resulting chiral forms are appropriate to lattice results obtained with operators already in use and could be used to study the restoration of taste symmetry in the continuum limit. I assume that the fourth root of the fermion determinant can be incorporated in staggered chiral perturbation theory using the replica method.

  19. Chiral Magnetic Effect in Hydrodynamic Approximation

    CERN Document Server

    Zakharov, Valentin I

    2012-01-01

    We review derivations of the chiral magnetic effect (ChME) in hydrodynamic approximation. The reader is assumed to be familiar with the basics of the effect. The main challenge now is to account for the strong interactions between the constituents of the fluid. The main result is that the ChME is not renormalized: in the hydrodynamic approximation it remains the same as for non-interacting chiral fermions moving in an external magnetic field. The key ingredients in the proof are general laws of thermodynamics and the Adler-Bardeen theorem for the chiral anomaly in external electromagnetic fields. The chiral magnetic effect in hydrodynamics represents a macroscopic manifestation of a quantum phenomenon (chiral anomaly). Moreover, one can argue that the current induced by the magnetic field is dissipation free and talk about a kind of "chiral superconductivity". More precise description is a ballistic transport along magnetic field taking place in equilibrium and in absence of a driving force. The basic limitat...

  20. Interplay between chiral and deconfinement phase transitions

    CERN Document Server

    Xu, Fukun; Chen, Huan; Huang, Mei

    2011-01-01

    By using the dressed Polyakov loop or dual chiral condensate as an equivalent order parameter of the deconfinement phase transition, we investigate the relation between the chiral and deconfinement phase transitions at finite temperature and density in the framework of three-flavor Nambu--Jona-Lasinio (NJL) model. It is found that in the chiral limit, the critical temperature for chiral phase transition coincides with that of the dressed Polyakov loop in the whole $(T,\\mu)$ plane. In the case of explicit chiral symmetry breaking, it is found that the phase transitions are flavor dependent. For each flavor, the transition temperature for chiral restoration $T_c^{\\chi}$ is smaller than that of the dressed Polyakov loop $T_c^{{\\cal D}}$ in the low baryon density region where the transition is a crossover, and, the two critical temperatures coincide in the high baryon density region where the phase transition is of first order. Therefore, there are two critical end points, i.e, $T_{CEP}^{u,d}$ and $T_{CEP}^{s}$ a...

  1. Enantioselectively controlled release of chiral drug (metoprolol) using chiral mesoporous silica materials

    Science.gov (United States)

    Guo, Zhen; Du, Yu; Liu, Xianbin; Ng, Siu-Choon; Chen, Yuan; Yang, Yanhui

    2010-04-01

    Chiral porous materials have attracted burgeoning attention on account of their potential applications in many areas, such as enantioseparation, chiral catalysis, chemical sensors and drug delivery. In this report, chiral mesoporous silica (CMS) materials with various pore sizes and structures were prepared using conventional achiral templates (other than chiral surfactant) and a chiral cobalt complex as co-template. The synthesized CMS materials were characterized by x-ray diffraction, nitrogen physisorption, scanning electron microscope and transmission electron microscope. These CMS materials, as carriers, were demonstrated to be able to control the enantioselective release of a representative chiral drug (metoprolol). The release kinetics, as modeled by the power law equation, suggested that the release profiles of metoprolol were remarkably dependent on the pore diameter and pore structure of CMS materials. More importantly, R- and S-enantiomers of metoprolol exhibited different release kinetics on CMS compared to the corresponding achiral mesoporous silica (ACMS), attributable to the existence of local chirality on the pore wall surface of CMS materials. The chirality of CMS materials on a molecular level was further substantiated by vibrational circular dichroism measurements.

  2. Enantioselectively controlled release of chiral drug (metoprolol) using chiral mesoporous silica materials

    Energy Technology Data Exchange (ETDEWEB)

    Guo Zhen; Liu Xianbin; Ng, Siu-Choon; Chen Yuan; Yang Yanhui [School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459 (Singapore); Du Yu, E-mail: du_yu@jlu.edu.cn, E-mail: yhyang@ntu.edu.sg [College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China)

    2010-04-23

    Chiral porous materials have attracted burgeoning attention on account of their potential applications in many areas, such as enantioseparation, chiral catalysis, chemical sensors and drug delivery. In this report, chiral mesoporous silica (CMS) materials with various pore sizes and structures were prepared using conventional achiral templates (other than chiral surfactant) and a chiral cobalt complex as co-template. The synthesized CMS materials were characterized by x-ray diffraction, nitrogen physisorption, scanning electron microscope and transmission electron microscope. These CMS materials, as carriers, were demonstrated to be able to control the enantioselective release of a representative chiral drug (metoprolol). The release kinetics, as modeled by the power law equation, suggested that the release profiles of metoprolol were remarkably dependent on the pore diameter and pore structure of CMS materials. More importantly, R- and S-enantiomers of metoprolol exhibited different release kinetics on CMS compared to the corresponding achiral mesoporous silica (ACMS), attributable to the existence of local chirality on the pore wall surface of CMS materials. The chirality of CMS materials on a molecular level was further substantiated by vibrational circular dichroism measurements.

  3. Enantioselectively controlled release of chiral drug (metoprolol) using chiral mesoporous silica materials

    International Nuclear Information System (INIS)

    Chiral porous materials have attracted burgeoning attention on account of their potential applications in many areas, such as enantioseparation, chiral catalysis, chemical sensors and drug delivery. In this report, chiral mesoporous silica (CMS) materials with various pore sizes and structures were prepared using conventional achiral templates (other than chiral surfactant) and a chiral cobalt complex as co-template. The synthesized CMS materials were characterized by x-ray diffraction, nitrogen physisorption, scanning electron microscope and transmission electron microscope. These CMS materials, as carriers, were demonstrated to be able to control the enantioselective release of a representative chiral drug (metoprolol). The release kinetics, as modeled by the power law equation, suggested that the release profiles of metoprolol were remarkably dependent on the pore diameter and pore structure of CMS materials. More importantly, R- and S-enantiomers of metoprolol exhibited different release kinetics on CMS compared to the corresponding achiral mesoporous silica (ACMS), attributable to the existence of local chirality on the pore wall surface of CMS materials. The chirality of CMS materials on a molecular level was further substantiated by vibrational circular dichroism measurements.

  4. Developing a Practical Chiral Toolbox for Asymmetric Catalytic Reactions

    Institute of Scientific and Technical Information of China (English)

    ZHANG; XuMu

    2001-01-01

    Chiral Quest's Toolbox Approach: During the last several decades, chemists have made major progress in discovering man-made catalysts to perform challenging asymmetric transformations. However, there is no universal chiral ligand or catalyst for solving problems in enantioselective transformations. The focus of Chiral Quest's research is to develop a useful chiral toolbox for strategically important asymmetric catalytic reactions by inventing a diverse set of novel chiral ligands and combining them with transition metals as effective enantioselective catalysts. The toolbox approach addresses significant problems in organic stereochemistry and has resulted in practical methods for the synthesis of chiral pharmaceuticals and agrochemicals  ……

  5. Developing a Practical Chiral Toolbox for Asymmetric Catalytic Reactions

    Institute of Scientific and Technical Information of China (English)

    ZHANG XuMu

    2001-01-01

    @@ Chiral Quest's Toolbox Approach: During the last several decades, chemists have made major progress in discovering man-made catalysts to perform challenging asymmetric transformations. However, there is no universal chiral ligand or catalyst for solving problems in enantioselective transformations. The focus of Chiral Quest's research is to develop a useful chiral toolbox for strategically important asymmetric catalytic reactions by inventing a diverse set of novel chiral ligands and combining them with transition metals as effective enantioselective catalysts. The toolbox approach addresses significant problems in organic stereochemistry and has resulted in practical methods for the synthesis of chiral pharmaceuticals and agrochemicals

  6. Chiral dynamics in U(3) unitary chiral perturbation theory

    International Nuclear Information System (INIS)

    We perform a complete one-loop calculation of meson-meson scattering, and of the scalar and pseudoscalar form factors in U(3) chiral perturbation theory with the inclusion of explicit resonance fields. This effective field theory takes into account the low-energy effects of the QCD UA(1) anomaly explicitly in the dynamics. The calculations are supplied by non-perturbative unitarization techniques that provide the final results for the meson-meson scattering partial waves and the scalar form factors considered. We present thorough analyses on the scattering data, resonance spectroscopy, spectral functions, Weinberg-like sum rules and semi-local duality. The last two requirements establish relations between the scalar spectrum with the pseudoscalar and vector ones, respectively. The NC extrapolation of the various quantities is studied as well. The fulfillment of all these non-trivial aspects of the QCD dynamics by our results gives a strong support to the emerging picture for the scalar dynamics and its related spectrum.

  7. Formation of Enhanced Uniform Chiral Fields in Symmetric Dimer Nanostructures.

    Science.gov (United States)

    Tian, Xiaorui; Fang, Yurui; Sun, Mengtao

    2015-01-01

    Chiral fields with large optical chirality are very important in chiral molecules analysis, sensing and other measurements. Plasmonic nanostructures have been proposed to realize such super chiral fields for enhancing weak chiral signals. However, most of them cannot provide uniform chiral near-fields close to the structures, which makes these nanostructures not so efficient for applications. Plasmonic helical nanostructures and blocked squares have been proved to provide uniform chiral near-fields, but structure fabrication is a challenge. In this paper, we show that very simple plasmonic dimer structures can provide uniform chiral fields in the gaps with large enhancement of both near electric fields and chiral fields under linearly polarized light illumination with polarization off the dimer axis at dipole resonance. An analytical dipole model is utilized to explain this behavior theoretically. 30 times of volume averaged chiral field enhancement is gotten in the whole gap. Chiral fields with opposite handedness can be obtained simply by changing the polarization to the other side of the dimer axis. It is especially useful in Raman optical activity measurement and chiral sensing of small quantity of chiral molecule. PMID:26621558

  8. Chiral dynamics and peripheral transverse densities

    Energy Technology Data Exchange (ETDEWEB)

    Granados, Carlos G. [Uppsala University (Sweden); Weiss, Christian [JLAB, Newport News, VA (United States)

    2014-01-01

    In the partonic (or light-front) description of relativistic systems the electromagnetic form factors are expressed in terms of frame-independent charge and magnetization densities in transverse space. This formulation allows one to identify the chiral components of nucleon structure as the peripheral densities at transverse distances b = O(M{sub {pi}}{sup -1}) and compute them in a parametrically controlled manner. A dispersion relation connects the large-distance behavior of the transverse charge and magnetization densities to the spectral functions of the Dirac and Pauli form factors near the two--pion threshold at timelike t = 4 M{ sub {pi}}{sup 2}, which can be computed in relativistic chiral effective field theory. Using the leading-order approximation we (a) derive the asymptotic behavior (Yukawa tail) of the isovector transverse densities in the "chiral" region b = O(M{sub {pi}}{sup -1}) and the "molecular" region b = O(M{sub N}{sup 2}/M{sub {pi}}{sup 3}); (b) perform the heavy-baryon expansion of the transverse densities; (c) explain the relative magnitude of the peripheral charge and magnetization densities in a simple mechanical picture; (d) include Delta isobar intermediate states and study the peripheral transverse densities in the large-N{ sub c} limit of QCD; (e) quantify the region of transverse distances where the chiral components of the densities are numerically dominant; (f) calculate the chiral divergences of the b{sup 2}-weighted moments of the isovector transverse densities (charge and anomalous magnetic radii) in the limit M{sub {pi}} -> 0 and determine their spatial support. Our approach provides a concise formulation of the spatial structure of the nucleon's chiral component and offers new insights into basic properties of the chiral expansion. It relates the information extracted from low-t elastic form factors to the generalized parton distributions probed in peripheral high-energy scattering processes.

  9. Search for chirality in 109Ag

    International Nuclear Information System (INIS)

    Complete text of publication follows. The existence of nuclear chirality is one of the most intriguing questions of contemporary high-spin nuclear structure studies. Rotational doublet-band candidates for chiral structures have been observed mostly in two regions of the nuclear chart: around 134Pr, and around 104Rh. In this second region chirality in the Rh isotopes are rather well studied, chiral doubling have also been observed in 100Tc, however, results obtained for chirality in the studied Ag nuclei (105Ag and 106Ag) look rather contradictory. Thus, it is interesting to study these doublet bands in the nearby higher-mass Ag nuclei. In order to search for a chiral-candidate partner band to the yrast πg9/2v(h11/2)2 band in 109Ag, high-spin states of this nucleus have been studied using the 96Zr(18O,p4n) reaction. The experiment was performed at iThemba LABS using 8 Clover detectors of the AFRODITE array and the DIAMANT charged-particle array to detect the γ-rays and the charged particles, respectively. Altogether ∼140 million γγ-coincidence events were collected. Approximately 10 million events of them correspond to the reaction channel producing 109Ag. No chiral candidate partner band has been found to the πg9/2v(h11/2)2 band with this statistics, however, the level scheme could be extended by several new levels and γ-transitions. A preliminary level scheme of 109Ag obtained from the ongoing data analysis is shown in Fig. 1

  10. Chiral Properties in ^134Pr

    Science.gov (United States)

    Starosta, K.; Chiara, C. J.; Fossan, D. B.; Koike, T.; Beausang, C. W.; Hecht, A. A.; Boston, A. J.; Chantler, H. J.; Paul, E. S.; Scraggs, H. C.; Simons, A.; Wadsworth, R.; Clark, R. M.

    2001-04-01

    The πh_11/2νh_11/2 doublet bands in ^134Pr, which represent the best evidence to date for chiral symmetry breaking in odd-odd nuclei [1], were investigated with the GAMMASPHERE array using the ^116Cd(^23Na,5n) reaction at 115 MeV. From thin-target data, the nearly degenerate ΔI=1 side band was extended from a 9^+ bandhead up to a spin of 24^+ with E2 crossovers, a total of 15 units of spin, while the main yrast band was observed from an 8^+ bandhead to 24^+. Measured γ-ray intensities suggest a staggering of the B(M1)/B(E2) ratios in the main band with the ratio smaller for even-spin initial states; these compare well with those of other N=75 isotones. Relative transition rates for γ-rays linking the doublet bands have also been extracted. Analysis of backed-target data aimed at absolute transition rates is underway. The results will be compared to calculations with particle-hole triaxial-rotor and 3-D TAC models. [1mm] [1] C.M.Petrache, et al., Nucl.Phys.A597(1996)106; V.I.Dimitrov, et al., PRL 84(2000)5732; K. Starosta, et al., PRL 86(2001).

  11. Magnetohydrodynamics of Chiral Relativistic Fluids

    CERN Document Server

    Boyarsky, Alexey; Ruchayskiy, Oleg

    2015-01-01

    We study the dynamics of a plasma of charged relativistic fermions at very high temperature $T\\gg m$, where $m$ is the fermion mass, coupled to the electromagnetic field. In particular, we derive a magneto-hydrodynamical description of the evolution of such a plasma. We show that, as compared to conventional MHD for a plasma of non-relativistic particles, the hydrodynamical description of the relativistic plasma involves new degrees of freedom described by a pseudo-scalar field originating in a local asymmetry in the densities of left-handed and right-handed fermions. This field can be interpreted as an effective axion field. Taking into account the chiral anomaly we present dynamical equations for the evolution of this field, as well as of other fields appearing in the MHD description of the plasma. Due to its non-linear coupling to helical magnetic fields, the axion field significantly affects the dynamics of a magnetized plasma and can give rise to a novel type of inverse cascade.

  12. About chiral models of dense matter and its magnetic properties

    International Nuclear Information System (INIS)

    The chiral models of dense nucleon matter are discussed. The quark matter with broken chiral symmetry is described. The magnetic properties of dense matter are presented and conclusions are given. 37 refs. (A.S.)

  13. Enantioselective catalytic syntheses of alpha-branched chiral amines

    DEFF Research Database (Denmark)

    Brase, S.; Baumann, T.; Dahmen, S.;

    2007-01-01

    Chiral amines play a pivotal role in fine chemical and natural product syntheses and the design of novel materials.......Chiral amines play a pivotal role in fine chemical and natural product syntheses and the design of novel materials....

  14. The Practical Asymmetric Syntheses of Key Chiral Intermediates of Chiral Drug from Four-Carbon Chiral Pool

    Institute of Scientific and Technical Information of China (English)

    MI; AiQiao

    2001-01-01

    (S)-or (R)-2-Amino-4-phenylbutyric acid and (S)-or (R)-2-hydroxy-4-phenylbutyric acid and their ethyl esters are key chiral intermediates for the preparation of angiotensin converting enzyme inhibitors (ACEI) and other chiral drugs. Their practically asymmetric synthetic methods in large scale from four-carbon chiral pool, commercially available L-aspartic acid and L-malic acid, will be presented (as scheme).  (S)-2-Amino-4-phenylbutyric acid and its ethyl ester hydrochloride were prepared from the easily available L-aspartic acid via activation by forming anhydride hydrochloride, Friedel-Crafts reaction with benzene, hydrogenolysis and esterification with ethanol in the presence of thionyl chloride in overall yield of 80% and 73.6% respectively with 99% ee. We first used amino acid anhydride hydrochloride as the acylating agent in Friedel-Crafts reaction without racemization. [1]……

  15. The Practical Asymmetric Syntheses of Key Chiral Intermediates of Chiral Drug from Four-Carbon Chiral Pool

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ (S)-or (R)-2-Amino-4-phenylbutyric acid and (S)-or (R)-2-hydroxy-4-phenylbutyric acid and their ethyl esters are key chiral intermediates for the preparation of angiotensin converting enzyme inhibitors (ACEI) and other chiral drugs. Their practically asymmetric synthetic methods in large scale from four-carbon chiral pool, commercially available L-aspartic acid and L-malic acid, will be presented (as scheme). (S)-2-Amino-4-phenylbutyric acid and its ethyl ester hydrochloride were prepared from the easily available L-aspartic acid via activation by forming anhydride hydrochloride, Friedel-Crafts reaction with benzene, hydrogenolysis and esterification with ethanol in the presence of thionyl chloride in overall yield of 80% and 73.6% respectively with 99% ee. We first used amino acid anhydride hydrochloride as the acylating agent in Friedel-Crafts reaction without racemization. [1

  16. Two chiral nonet model with massless quarks

    CERN Document Server

    Fariborz, Amir H; Schechter, Joseph

    2007-01-01

    We present a detailed study of a linear sigma model containing one chiral nonet transforming under U(1)$_A$ as a quark-antiquark composite and another chiral nonet transforming as a diquark-anti diquark composite (or, equivalently from a symmetry point of view, as a two meson molecule). The model provides an intuitive explanation of a current puzzle in low energy QCD: Recent work has suggested the existence of a lighter than 1 GeV nonet of scalar mesons which behave like four quark composites. On the other hand, the validity of a spontaneously broken chiral symmetric description would suggest that these states be chiral partners of the light pseudoscalar mesons, which are two quark composites. The model solves the problem by starting with the two chiral nonets mentioned and allowing them to mix with each other. The input of physical masses in the SU(3) invariant limit for two scalar octets and an "excited" pion octet results in a mixing pattern wherein the light scalars have a large four quark content while t...

  17. Two chiral nonet model with massless quarks

    International Nuclear Information System (INIS)

    We present a detailed study of a linear sigma model containing one chiral nonet transforming under U(1)A as a quark-antiquark composite and another chiral nonet transforming as a diquark-antidiquark composite (or, equivalently from a symmetry point of view, as a two meson molecule). The model provides an intuitive explanation of a current puzzle in low energy QCD: Recent work has suggested the existence of a lighter than 1 GeV nonet of scalar mesons which behave like four quark composites. On the other hand, the validity of a spontaneously broken chiral symmetric description would suggest that these states be chiral partners of the light pseudoscalar mesons, which are two quark composites. The model solves the problem by starting with the two chiral nonets mentioned and allowing them to mix with each other. The input of physical masses in the SU(3) invariant limit for two scalar octets and an excited pion octet results in a mixing pattern wherein the light scalars have a large four quark content while the light pseudoscalars have a large two quark content. One light isosinglet scalar is exceptionally light. In addition, the pion pion scattering is also studied and the current algebra theorem is verified for massless pions which contain some four quark admixture

  18. Chiral dynamics of heavy-light mesons

    International Nuclear Information System (INIS)

    This thesis focuses on the physics of heavy-light mesons, i.e. quark-antiquark systems composed of a heavy (c or b) and a light (u, d or s) quark. The light-quark sector is treated within the framework of chiral effective field theory. Recent lattice QCD computations have progressed in determining the decay constants of charmed mesons and the scattering lengths of Nambu-Goldstone bosons (pions, kaons) off D mesons. These computations are performed for light quark masses larger than the physical ones. A chiral extrapolation down to physical masses is necessary. It is commonly performed using chiral perturbation theory. The related systematical uncertainties have to be examined carefully. In this thesis it is shown how these uncertainties can be reduced significantly by taking into account relativistic effects in the chiral extrapolations. As a byproduct, estimates are presented for several physical quantities that are related by heavy-quark spin and flavor symmetry. Furthermore, the investigation of the light-quark mass dependence of the scattering lengths of Nambu-Goldstone bosons off D mesons provides important information on the nature of one of the intriguing newly discovered resonances, the D*s0(2317). It is shown that this resonance can be dynamically generated from the coupled-channels DK interaction without a priori assumption of its existence. Finally we demonstrate how the underlying framework, unitarized chiral perturbation theory, can be improved by the inclusion of intermediate states with off-the-mass-shell kinematics.

  19. On the chiral imbalance and Weibel instabilities

    Science.gov (United States)

    Kumar, Avdhesh; Bhatt, Jitesh R.; Kaw, P. K.

    2016-06-01

    We study the chiral-imbalance and the Weibel instabilities in presence of the quantum anomaly using the Berry-curvature modified kinetic equation. We argue that in many realistic situations, e.g. relativistic heavy-ion collisions, both the instabilities can occur simultaneously. The Weibel instability depends on the momentum anisotropy parameter ξ and the angle (θn) between the propagation vector and the anisotropy direction. It has maximum growth rate at θn = 0 while θn = π / 2 corresponds to a damping. On the other hand the pure chiral-imbalance instability occurs in an isotropic plasma and depends on difference between the chiral chemical potentials of right and left-handed particles. It is shown that when θn = 0, only for a very small values of the anisotropic parameter ξ ∼ξc, growth rates of the both instabilities are comparable. For the cases ξc < ξ ≪ 1 or ξ ≳ 1 at θn = 0, the Weibel modes dominate over the chiral-imbalance instability if μ5 / T ≤ 1. However, when μ5 / T ≥ 1, it is possible to have dominance of the chiral-imbalance modes at certain values of θn for an arbitrary ξ.

  20. Chiral superfluidity for the heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Kalaydzhyan, T. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Institute of Theoretical and Experimental Physics, Moscow (Russian Federation)

    2013-02-15

    We argue that the strongly coupled quark-gluon plasma formed at LHC and RHIC can be considered as a chiral superfluid. The ''normal'' component of the fluid is the thermalized matter in common sense, while the ''superfluid'' part consists of long wavelength (chiral) fermionic states moving independently. We use the bosonization procedure with a finite cut-off and obtain a dynamical axion-like field out of the chiral fermionic modes. Then we use relativistic hydrodynamics for macroscopic description of the effective theory obtained after the bosonization. Finally, solving the hydrodynamic equations in gradient expansion, we find that in the presence of external electromagnetic fields the motion of the ''superfluid'' component gives rise to the chiral magnetic, chiral electric and dipole wave effects. Latter two effects are specific for a two-component fluid, which provides us with crucial experimental tests of the model. By considering probe quarks one can show that the fermionic spectrum at the intermediate temperatures (T{sub c}

  1. Chiral density wave in nuclear matter

    International Nuclear Information System (INIS)

    Inspired by recent work on inhomogeneous chiral condensation in cold, dense quark matter within models featuring quark degrees of freedom, we investigate the chiral density-wave solution in nuclear matter at zero temperature and nonvanishing baryon number density in the framework of the so-called extended linear sigma model (eLSM). The eLSM is an effective model for the strong interaction based on the global chiral symmetry of quantum chromodynamics (QCD). It contains scalar, pseudoscalar, vector, and axial-vector mesons as well as baryons. In the latter sector, the nucleon and its chiral partner are introduced as parity doublets in the mirror assignment. The eLSM simultaneously provides a good description of hadrons in vacuum as well as nuclear matter ground-state properties. We find that an inhomogeneous phase in the form of a chiral density wave is realized, but only for densities larger than 2.4ρ0, where ρ0 is the nuclear matter ground-state density

  2. Chirality dependent spin polarization of carbon nanotubes

    Science.gov (United States)

    Wang, Jia; Jiang, Wanrun; Wang, Bo; Gao, Yang; Wang, Zhigang; Zhang, Rui-Qin

    2016-02-01

    The spin polarization of carbon nanotubes (CNTs) offers a tunable building block for spintronic devices and is also crucial for realizing carbon-based electronics. However, the effect of chiral CNTs is still unclear. In this paper, we use the density functional theory (DFT) method to investigate the spin polarization of a series of typical finite-length chiral CNTs (9, m). The results show that the spin density of chiral CNTs (9, m) decreases gradually with the increase in m and vanishes altogether when m is larger than or equal to 6. The armchair edge units on both ends of the (9, m) CNTs exhibit a clear inhibition of spin polarization, allowing control of the spin density of (9, m) CNTs by adjusting the number of armchair edge units on the tube end. Furthermore, analysis of the orbitals shows that the spin of the ground state for (9, m) CNTs mainly comes from the contributions of the frontier molecular orbitals (MOs), and the energy gap decreases gradually with the spin density for chiral CNTs. Our work further develops the study of the spin polarization of CNTs and provides a strategy for controlling the spin polarization of functional molecular devices through chiral vector adjustment.

  3. Chiral heat wave and mixed waves in kinetic theory

    CERN Document Server

    Frenklakh, D

    2016-01-01

    We study collective excitations in hot rotating chiral media in presence of magnetic field in kinetic theory, namely Chiral Heat Wave and its' mixings with Chiral Vortical Wave and Chiral Magnetic Wave. Our results for velocities of these waves have slight alterations from those obtained earlier. We explain the origin of these alterations and also give the most general expressions for the velocities of all these waves in hydrodynamic approach.

  4. Chirality - The forthcoming 160th Anniversary of Pasteur's Discovery

    OpenAIRE

    Molčanov, Krešimir; Kojić-Prodić, Biserka

    2007-01-01

    The presented review on chirality is dedicated to the centennial birth anniversary of Nobel laureate Vladimir Prelog and 160 years of Pasteur's discovery of chirality on tartrates. Chirality has been recognized in nature by artists and architects, who have used it for decorations and basic constructions, as shown in the Introduction. The progress of science through history has enabled the gathering of knowledge on chirality and its many ways of application. The key historical discoveries abou...

  5. Inhomogeneous Polyakov loop induced by inhomogeneous chiral condensates

    Energy Technology Data Exchange (ETDEWEB)

    Hayata, Tomoya, E-mail: hayata@riken.jp [Department of Physics, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Theoretical Research Division, Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan); Yamamoto, Arata [Department of Physics, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Theoretical Research Division, Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan)

    2015-05-11

    We study the spatial inhomogeneity of the Polyakov loop induced by inhomogeneous chiral condensates. We formulate an effective model of gluons on the background fields of chiral condensates, and perform its lattice simulation. On the background of inhomogeneous chiral condensates, the Polyakov loop exhibits an in-phase spatial oscillation with the chiral condensates. We also analyze the heavy quark potential and show that the inhomogeneous Polyakov loop indicates the inhomogeneous confinement of heavy quarks.

  6. Inhomogeneous Polyakov loop induced by inhomogeneous chiral condensates

    Directory of Open Access Journals (Sweden)

    Tomoya Hayata

    2015-05-01

    Full Text Available We study the spatial inhomogeneity of the Polyakov loop induced by inhomogeneous chiral condensates. We formulate an effective model of gluons on the background fields of chiral condensates, and perform its lattice simulation. On the background of inhomogeneous chiral condensates, the Polyakov loop exhibits an in-phase spatial oscillation with the chiral condensates. We also analyze the heavy quark potential and show that the inhomogeneous Polyakov loop indicates the inhomogeneous confinement of heavy quarks.

  7. Two-color QCD with chiral chemical potential

    Science.gov (United States)

    Braguta, V. V.; Goy, V. A.; Ilgenfritz, E.-M.; Kotov, A. Yu.; Molochkov, A. V.; Müller-Preussker, M.; Petersson, B.; Schreiber, A.

    2016-01-01

    The phase diagram of two-color QCD with a chiral chemical potential is studied on the lattice. The focus is on the confinement/deconfinement phase transition and the breaking/restoration of chiral symmetry. The simulations are carried out with dynamical staggered fermions without rooting. The dependence of the Polyakov loop, the chiral condensate and the corresponding susceptibilities on the chiral chemical potential and the temperature are presented.

  8. Inhomogeneous Polyakov loop induced by inhomogeneous chiral condensates

    Science.gov (United States)

    Hayata, Tomoya; Yamamoto, Arata

    2015-05-01

    We study the spatial inhomogeneity of the Polyakov loop induced by inhomogeneous chiral condensates. We formulate an effective model of gluons on the background fields of chiral condensates, and perform its lattice simulation. On the background of inhomogeneous chiral condensates, the Polyakov loop exhibits an in-phase spatial oscillation with the chiral condensates. We also analyze the heavy quark potential and show that the inhomogeneous Polyakov loop indicates the inhomogeneous confinement of heavy quarks.

  9. Inhomogeneous Polyakov loop induced by inhomogeneous chiral condensates

    OpenAIRE

    Tomoya Hayata; Arata Yamamoto

    2015-01-01

    We study the spatial inhomogeneity of the Polyakov loop induced by inhomogeneous chiral condensates. We formulate an effective model of gluons on the background fields of chiral condensates, and perform its lattice simulation. On the background of inhomogeneous chiral condensates, the Polyakov loop exhibits an in-phase spatial oscillation with the chiral condensates. We also analyze the heavy quark potential and show that the inhomogeneous Polyakov loop indicates the inhomogeneous confinement...

  10. Novel Lifshitz point for chiral transition in the magnetic field

    Directory of Open Access Journals (Sweden)

    Toshitaka Tatsumi

    2015-04-01

    Full Text Available Based on the generalized Ginzburg–Landau theory, chiral phase transition is discussed in the presence of magnetic field. Considering the chiral density wave we show that chiral anomaly gives rise to an inhomogeneous chiral phase for nonzero quark-number chemical potential. Novel Lifshitz point appears on the vanishing chemical potential line, which may be directly explored by the lattice QCD simulation.

  11. Elastic properties of chiral, anti-chiral, and hierarchical honeycombs: A simple energy-based approach

    Directory of Open Access Journals (Sweden)

    Davood Mousanezhad

    2016-03-01

    Full Text Available The effects of two geometric refinement strategies widespread in natural structures, chirality and self-similar hierarchy, on the in-plane elastic response of two-dimensional honeycombs were studied systematically. Simple closed-form expressions were derived for the elastic moduli of several chiral, anti-chiral, and hierarchical honeycombs with hexagon and square based networks. Finite element analysis was employed to validate the analytical estimates of the elastic moduli. The results were also compared with the numerical and experimental data available in the literature. We found that introducing a hierarchical refinement increases the Young’s modulus of hexagon based honeycombs while decreases their shear modulus. For square based honeycombs, hierarchy increases the shear modulus while decreasing their Young’s modulus. Introducing chirality was shown to always decrease the Young’s modulus and Poisson’s ratio of the structure. However, chirality remains the only route to auxeticity. In particular, we found that anti-tetra-chiral structures were capable of simultaneously exhibiting anisotropy, auxeticity, and remarkably low shear modulus as the magnitude of the chirality of the unit cell increases.

  12. Chiral symmetry in hadron physics methods and ideas of chiral symmetry

    International Nuclear Information System (INIS)

    Methods and ideas of chiral symmetry is presented based on a lecture note to help the future researches in hadron dynamics along with the chiral symmetry. The chiral symmetry was originally developed as the symmetry between currents before the discovery of QCD. It has come to be understood in principle by now that the symmetry is spontaneously broken and only the part of flavor symmetry remains explicitly. In QCD, however, the chiral symmetry has come to be regarded as the base of the symmetry of the global flavor space of quarks. One of the recent topics of the lattice gauge theory is how the hadron properties will change when the broken symmetry is going to be restored. Since the chiral symmetry is global, it is different from gauge symmetry which is local. It explains the degeneracy of hadron masses and relations between the elements of S-matrix in which same number of particles are included. In practice, however, the symmetry of the axial part is spontaneously broken and pions which behave like gauge particles come to play. Chiral symmetry is defined as the (internal) flavor symmetry for the two independent chirality states of quarks. It discriminates two different fundamental quarks defined for the Lorentz groups O(4) - SL(2, C). The symmetry transformation itself is, however, different from the chirality. They should not be confused. In this lecture note, fundamental properties of pions are described on the basis of the interaction with nucleons at first. General properties of the chiral symmetry and some of the low energy theorems on current algebra are introduced. Then, linear sigma model and nonlinear sigma model are introduced. Then the Skyrme-model, which provides an idea as important as quarks, is explained. One of the interesting topics at present is to restore the broken axial symmetry experimentally to investigate the mechanism of symmetry breaking. (S. Funahashi)

  13. A strict QCD inequality and mechanisms for chiral symmetry breaking

    International Nuclear Information System (INIS)

    A strict QCD inequality allows one to discuss mechanisms proposed for breaking the chiral symmetry in QCD. ''Order parameters'' are identified such that if sufficiently many gauge field configurations contribute to them, spontaneous chiral symmetry breaking follows. As an application the role of instantons is discussed in chiral symmetry breaking in QCD. (orig.)

  14. How is chiral symmetry restored at finite density?

    OpenAIRE

    Tatsumi, T.; Nakano, E.

    2005-01-01

    Taking into account pseudoscalar as well as scalar condensates, we reexamine the chiral restoration path on the chiral manifold. We shall see both condensates coherently produce a density wave at a certain density, which delays chiral restoration as density or temperature is increased.

  15. Quantized chiral magnetic current from reconnections of magnetic flux

    CERN Document Server

    Hirono, Yuji; Yin, Yi

    2016-01-01

    We introduce a new mechanism for the chiral magnetic effect that does not require an initial chirality imbalance. The chiral magnetic current is generated by reconnections of magnetic flux that change magnetic helicity of the system. The resulting current is entirely determined by the change of magnetic helicity, and is therefore quantized.

  16. Asymmetric Catalytic Reactions Catalyzed by Chiral Titanium Complexes

    Institute of Scientific and Technical Information of China (English)

    FENG; XiaoMing

    2001-01-01

    Chiral titanium complexes is very importance catalyst to asymmetric catalytic reactions. A series of catalytic systems based on titanium-chiral ligands complexes has been reported. This presentation will discuss some of our recent progress on asymmetric catalytic reactions catalyzed by chiral titanium complexes.  ……

  17. Asymmetric Catalytic Reactions Catalyzed by Chiral Titanium Complexes

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Chiral titanium complexes is very importance catalyst to asymmetric catalytic reactions. A series of catalytic systems based on titanium-chiral ligands complexes has been reported. This presentation will discuss some of our recent progress on asymmetric catalytic reactions catalyzed by chiral titanium complexes.

  18. Chiral Ordering in the Four-Dimensional XY Spin Glass

    OpenAIRE

    Jain, S.

    1997-01-01

    The chiral glass behaviour of the nearest-neighbour random-bond XY spin glass in four dimensions is studied by Monte Carlo simulations. A chiral glass transition at $T_{cg}=0.90\\pm 0.05$ is found by a finite-size scaling analysis of the results. The associated chiral correlation-length exponent is estimated to be $\

  19. Chiral doublet bands and energy-level crossing

    Institute of Scientific and Technical Information of China (English)

    QI Bin; MENG Jie; ZHANG Shuang-Quan; WANG Shou-Yu; PENG Jing

    2009-01-01

    Different definitions for chiral doublet bands based on excitation energies, B(E2) and B(M1) respectively are discussed in the triaxial particle rotor model. For the ideal chiral geometry, the selection rules of the electromagnetic transitions in different band definitions are illustrated. It is also shown that the energy-level crossings between chiral doublet bands may occur.

  20. Viscoelastic modes in chiral liquid crystals

    Indian Academy of Sciences (India)

    K A Suresh

    2003-08-01

    Viscoelastic properties of liquid crystals are very important for applications like display technology. However, there are not many direct techniques to study them. In this review, we describe our studies on the viscoelastic modes of some chiral liquid crystals using dynamic light scattering. We discuss viscoelastic modes corresponding to the C director fluctuations in the chiral smectic C phase and the behaviour of the Goldstone-mode near the chiral smectic C–smectic A phase transition. In cholesteric liquid crystals, we consider the director fluctuations in a wavevector range comparable to the inverse pitch of the cholesteric. Here, the study of the scattered light in the vicinity of the Bragg reflection using a novel geometry will be presented.

  1. Magnetic test of chiral dynamics in QCD

    International Nuclear Information System (INIS)

    Strong magnetic fields in the range eB≫mπ2 effectively probe internal quark structure of chiral mesons and test basic parameters of the chiral theory, such as 〈q-barq〉,fπ. We argue on general grounds that 〈q-barq〉 should grow linearly with eB when charged quark degrees of freedom come into play. To make explicit estimates we extend the previously formulated chiral theory, including quark degrees of freedom, to the case of strong magnetic fields and show that the quark condensate |〈q-barq〉|u,d grows quadratically with eB for eB<0.2 GeV2 and linearly for higher field values. These results agree quantitatively with recent lattice data and differ from χPT predictions

  2. Chiral symmetry breaking in brane models

    International Nuclear Information System (INIS)

    We discuss the chiral symmetry breaking in general intersecting Dq/Dp brane models consisting of Nc Dq-branes and a single Dp-brane with an s-dimensional intersection. There exists a QCD-like theory localized at the intersection and the Dq/Dp model gives a holographic description of it. The rotational symmetry of directions transverse to both of the Dq and Dp-branes can be identified with a chiral symmetry, which is non-Abelian for certain cases. The asymptotic distance between the Dq-branes and the Dp-brane corresponds to a quark mass. By studying the probe Dp-brane dynamics in a Dq-brane background in the near horizon and large Nc limit we find that the chiral symmetry is spontaneously broken and there appear (pseudo-)Nambu-Goldstone bosons. We also discuss the models at finite temperature

  3. Chiral symmetry and strangeness at SIS energies

    International Nuclear Information System (INIS)

    In this talk we review the consequences of the chiral SU(3) symmetry for strangeness propagation in nuclear matter. Objects of crucial importance are the meson-baryon scattering amplitudes obtained within the chiral coupled-channel effective field theory. Results for antikaon and hyperon-resonance spectral functions in cold nuclear matter are presented and discussed. The importance of the Σ(1385) resonance for the subthreshold antikaon production in heavy-ion reaction at SIS is pointed out. The in-medium properties of the latter together with an antikaon spectral function based on chiral SU(3) dynamics suggest a significant enhancement of the π Λ → anti Κ N reaction in nuclear matter. (orig.)

  4. Chiral light by symmetric optical antennas

    CERN Document Server

    Mekonnen, Addis; Zubritskaya, Irina; Jönsson, Gustav Edman; Dmitriev, Alexandre

    2014-01-01

    Chirality is at the origin of life and is ubiquitous in nature. An object is deemed chiral if it is non-superimposable with its own mirror image. This relates to how circularly polarized light interacts with such object, a circular dichroism, the differential absorption of right and left circularly polarized light. According to the common understanding in biology, chemistry and physics, the circular dichroism results from an internal chiral structure or external symmetry breaking by illumination. We show that circular dichroism is possible with simple symmetric optical nanoantennas at symmetric illumination. We experimentally and theoretically demonstrate that two electromagnetic dipole-like modes with a phase lag, in principle, suffice to produce circular dichroism in achiral structure. Examples of the latter are all visible spectrum optical nanoantennas, symmetric nanoellipses and nanodimers. The simplicity and generality of this finding reveal a whole new significance of the electromagnetic design at a nan...

  5. Analysis of chiral symmetry breaking mechanism

    International Nuclear Information System (INIS)

    The renormalization group invariant quark condensate μ is determinate both from the consistent equation for quark condensate in the chiral limit and from the Schwinger-Dyson (SD) equation improved by the intermediate range QCD force singular like δ (q) which is associated with the gluon condensate. The solutions of μ in these two equations are consistent. We also obtain the critical strong coupling constant αc above which chiral symmetry breaks in two approaches. The nonperturbative kernel of the SD equation makes αc smaller and μ bigger. An intuitive picture of the condensation above αc is discussed. In addition, with the help of the Slavnov-Taylor-Ward (STW) identity we derive the equations for the nonperturbative quark propagator from SD equation in the presence of the intermediate-range force is also responsible for dynamical chiral symmetry breaking. (author)

  6. Planar Chiral, Ferrocene-Stabilized Silicon Cations.

    Science.gov (United States)

    Schmidt, Ruth K; Klare, Hendrik F T; Fröhlich, Roland; Oestreich, Martin

    2016-04-01

    The preparation of a series of planar chiral, ferrocenyl-substituted hydrosilanes as precursors of ferrocene-stabilized silicon cations is described. These molecules also feature stereogenicity at the silicon atom. The generation and (29) Si NMR spectroscopic characterization of the corresponding silicon cations is reported, and problems arising from interactions of the electron-deficient silicon atom and adjacent C(sp(3) )-H bonds or aromatic π donors are discussed. These issues are overcome by tethering another substituent at the silicon atom to the ferrocene backbone. The resulting annulation also imparts conformational rigidity and steric hindrance in such a way that the central chirality at the silicon atom is set with complete diastereocontrol. These chiral Lewis acid catalysts were then tested in difficult Diels-Alder reactions, but no enantioinduction was seen. PMID:26929105

  7. Weighted power counting and chiral dimensional regularization

    CERN Document Server

    Anselmi, Damiano

    2014-01-01

    We define a modified dimensional-regularization technique that overcomes several difficulties of the ordinary technique, and is specially designed to work efficiently in chiral and parity violating quantum field theories, in arbitrary dimensions greater than 2. When the dimension of spacetime is continued to complex values, spinors, vectors and tensors keep the components they have in the physical dimension, therefore the gamma matrices are the standard ones. Propagators are regularized with the help of evanescent higher-derivative kinetic terms, which are of Majorana type in the case of chiral fermions. If the new terms are organized in a clever way, weighted power counting provides an efficient control on the renormalization of the theory, and allows us to show that the resulting chiral dimensional regularization is consistent to all orders. The new technique considerably simplifies the proofs of properties that hold to all orders, and makes them suitable to be generalized to wider classes of models. Typica...

  8. Spontaneous chiral symmetry breaking in metamaterials

    Science.gov (United States)

    Liu, Mingkai; Powell, David A.; Shadrivov, Ilya V.; Lapine, Mikhail; Kivshar, Yuri S.

    2014-07-01

    Spontaneous chiral symmetry breaking underpins a variety of areas such as subatomic physics and biochemistry, and leads to an impressive range of fundamental phenomena. Here we show that this prominent effect is now available in artificial electromagnetic systems, enabled by the advent of magnetoelastic metamaterials where a mechanical degree of freedom leads to a rich variety of strong nonlinear effects such as bistability and self-oscillations. We report spontaneous symmetry breaking in torsional chiral magnetoelastic structures where two or more meta-molecules with opposite handedness are electromagnetically coupled, modifying the system stability. Importantly, we show that chiral symmetry breaking can be found in the stationary response of the system, and the effect is successfully demonstrated in a microwave pump-probe experiment. Such symmetry breaking can lead to a giant nonlinear polarization change, energy localization and mode splitting, which provides a new possibility for creating an artificial phase transition in metamaterials, analogous to that in ferrimagnetic domains.

  9. Chiral Bosons as solutions of the BV master equation 2D chiral gauge theories

    OpenAIRE

    Braga, N. R. F.; Montani, H.

    1994-01-01

    We construct the chiral Wess-Zumino term as a solution for the Batalin-Vilkovisky master equation for anomalous two-dimensional gauge theories, working in an extended field-antifield space, where the gauge group elements are introduced as additional degrees of freedom. We analyze the Abelian and the non-Abelian cases, calculating in both cases the BRST generator in order to show the physical equivalence between this chiral solution for the master equation and the usual (non-chiral) one.

  10. Chiral magnetic microspheres purified by centrifugal field flow fractionation and microspheres magnetic chiral chromatography for benzoin racemate separation

    OpenAIRE

    Tian, Ailin; Qi, Jing; Liu, Yating; Wang, Fengkang; Ito, Yoichiro; Wei, Yun

    2013-01-01

    Separation of enantiomers still remains a challenge due to their identical physical and chemical properties in a chiral environment, and the research on specific chiral selector along with separation techniques continues to be conducted to resolve individual enantiomers. In our laboratory the promising magnetic chiral microspheres Fe3O4@SiO2@cellulose-2, 3-bis (3, 5-dimethylphenylcarbamate) have been developed to facilitate the resolution using both its magnetic property and chiral recognitio...

  11. Physical properties of the chiral quantum baryon

    International Nuclear Information System (INIS)

    It is presented an account to understand the quantum chiral baryon, which a stable chiral soliton with baryon number one obtained after first quantization by collective coordinates. Starting from the exact series solution to the non-linear sigma model with the hedge-hog configuration, the values of several physical quantities (mass, axial weak coupling, gyromagnetic ratios and radii) as a function of the order of Pade approximants used as approximanted representations of the solution, are calculated. It turns out that consistent results may be obtained, but a better approximation should be developed. (author)

  12. Disoriented chiral condensate: Theory and phenomenology

    International Nuclear Information System (INIS)

    These notes are an abbreviated version of lectures given at the 1997 Zakopane School. They contain two topics. The first is a description in elementary terms of the basic ideas underlying the speculative hypothesis that pieces of strong-interaction vacuum with a rotated chiral order parameter, disoriented chiral condensate or DCC, might be produced in high energy elementary particle collisions. The second topic is a discussion of the phenomenological techniques which may be applied to data in order to experimentally search for the existence of DCC

  13. Chiral logarithms in the massless limit tamed.

    Science.gov (United States)

    Kivel, Nikolai; Polyakov, Maxim V; Vladimirov, Alexei

    2008-12-31

    We derive nonlinear recursion relations for the leading chiral logarithms (LLs) in massless theories. These relations not only provide a very efficient method of computation of LLs (e.g., the 33-loop contribution is calculated in a dozen of seconds on a PC) but also equip us with a powerful tool for the summation of the LLs. Our method is not limited to chiral perturbation theory only; it is pertinent to any nonrenormalizable effective field theory such as, for instance, the theory of critical phenomena, low-energy quantum gravity, etc. PMID:19437635

  14. Probing Chiral Interactions in Light Nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Nogga, A; Barrett, B R; Meissner, U; Witala, H; Epelbaum, E; Kamada, H; Navratil, P; Glockle, W; Vary, J P

    2004-01-08

    Chiral two- and three-nucleon interactions are studied in a few-nucleon systems. We investigate the cut-off dependence and convergence with respect to the chiral expansion. It is pointed out that the spectra of light nuclei are sensitive to the three-nucleon force structure. As an example, we present calculations of the 1{sup +} and 3{sup +} states of {sup 6}Li using the no-core shell model approach. The results show contributions of the next-to-next-to-leading order terms to the spectra, which are not correlated to the three-nucleon binding energy prediction.

  15. Absence of equilibrium chiral magnetic effect

    CERN Document Server

    Zubkov, M A

    2016-01-01

    We analyse the $3+1$ D equilibrium chiral magnetic effect (CME). We apply derivative expansion to the Wigner transform of the two - point Green function. This technique allows us to express the response of electric current to external electromagnetic field strength through the momentum space topological invariant. We consider the wide class of the lattice regularizations of quantum field theory (that includes, in particular, the regularization with Wilson fermions) and also certain lattice models of solid state physics (including those of Dirac semimetals). It appears, that in these models the mentioned topological invariant vanishes identically at nonzero chiral chemical potential. That means, that the bulk equilibrium CME is absent in those systems.

  16. Going chiral: overlap versus twisted mass fermions

    International Nuclear Information System (INIS)

    We compare the behavior of overlap fermions, which are chirally invariant, and of Wilson twisted mass fermions at full twist in the approach to the chiral limit. Our quenched simulations reveal that with both formulations of lattice fermions pion masses of O (250 MeV) can be reached in practical applications. Our comparison is done at a fixed value of the lattice spacing a ≅ 0.123 fm. A number of quantities are measured such as hadron masses, pseudoscalar decay constants and quark masses obtained from Ward identities. We also determine the axial vector renormalization constants in the case of overlap fermions. (author)

  17. Going chiral: overlap versus twisted mass fermions

    Energy Technology Data Exchange (ETDEWEB)

    Bietenholz, Wolfgang [Institut fuer Physik, Humboldt Universitaet zu Berlin, Newtonstr. 15, D-12489 Berlin (Germany); Capitani, Stefano [Institut fuer Physik/Theoretische Physik, Universitaet Graz, A-8010 Graz (Austria); Chiarappa, Thomas [NIC/DESY Zeuthen, Platanenallee 6, D-15738 Zeuthen (Germany)] [and others

    2004-12-01

    We compare the behavior of overlap fermions, which are chirally invariant, and of Wilson twisted mass fermions at full twist in the approach to the chiral limit. Our quenched simulations reveal that with both formulations of lattice fermions pion masses of O (250 MeV) can be reached in practical applications. Our comparison is done at a fixed value of the lattice spacing a {approx_equal} 0.123 fm. A number of quantities are measured such as hadron masses, pseudoscalar decay constants and quark masses obtained from Ward identities. We also determine the axial vector renormalization constants in the case of overlap fermions. (author)

  18. Relating lattice QCD and chiral perturbation theory

    International Nuclear Information System (INIS)

    We present simulation results for lattice QCD using chiral lattice fermions, which obey the Ginsparg Wilson relation. After discuss first conceptual issues, and then numerical results. In the epsilon regime we evaluated the low lying modes in Dirac spectrum and the axial correlation functions for very light quarks. These provide information about the leading low energy constants in chiral perturbation theory: the pion decay constant and the scalar condensate. In the p regime we measured light meson masses, the PCAC quark mass and the renormalisation constant ZA

  19. Possible chiral bands in 194Tl

    International Nuclear Information System (INIS)

    High spin states in 194Tl, excited through the 181Ta(18O,5n) fusion evaporation reaction, were studied using the AFRODITE array at iThemba LABS. Candidate chiral bands built on the πh9/2 x νi13/21 configuration were found. Furthermore these bands were observed through a band crossing caused by the excitation of a νi13/2 pair. Above the band crossing the excitation energies remain close, suggesting that chirality may persist for the four quasiparticle configuration too.

  20. Anomalous Hall effect for semiclassical chiral fermions

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Pengming, E-mail: zhpm@impcas.ac.cn [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou (China); Horváthy, P.A., E-mail: horvathy@lmpt.univ-tours.fr [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou (China); Laboratoire de Mathématiques et de Physique Théorique, Université de Tours (France)

    2015-03-06

    Semiclassical chiral fermions manifest the anomalous spin-Hall effect: when put into a pure electric field they suffer a side jump, analogous to what happens to their massive counterparts in non-commutative mechanics. The transverse shift is consistent with the conservation of the angular momentum. In a pure magnetic field, instead, spiraling motion is found. Motion in Hall-type perpendicular electric and magnetic fields is also studied. - Highlights: • Chiral fermions exhibit an anomalous spin-Hall effect. • Transverse shift appears in a pure electric field. • In a pure magnetic field spiraling motion is found.

  1. Pentaquarks in chiral color dielectric model

    Indian Academy of Sciences (India)

    S C Pathak

    2006-04-01

    Recent experiments indicate that a narrow baryonic state having strangeness +1 and mass of about 1540 MeV may be existing. Such a state was predicted in chiral model by Diakonov et al. In this work I compute the mass and width of this state in chiral color dielectric model. I show that the computed width is about 30 MeV. I find that the mass of the state can be fitted to the experimentally observed mass by invoking a color neutral vector field and its interaction with the quarks.

  2. Charged pion condensation in the chiral limit

    International Nuclear Information System (INIS)

    We examine, in the chiral limit where the up and down quark masses are vanishingly small, the stability of the pure neutron ground state to small fluctuations due to charge and baryon number conserving strong interactions. It is shown that the ground state energy density as a function of pion field expectation value is determined by Weinberg's baryon two-body potential and by a calculable neutron-proton mass difference in the medium. This provides some insight into the competing physical effects that play a role in determining whether a charged pion condensate forms in dense nuclear matter. We find that in the chiral limit these effects suppress charged pion condensation. (orig.)

  3. Chiral pesticides: Identification, description, and environmental implications

    Science.gov (United States)

    Ulrich, Elin M.; Morrison, Candice N.; Goldsmith, Michael R.; Foreman, William T.

    2012-01-01

    Anthropogenic chemicals, including pesticides, are a major source of contamination and pollution in the environment. Pesticides have many positive uses: increased food production, decreased damage to crops and structures, reduced disease vector populations, and more. Nevertheless, pesticide exposure can pose risks to humans and the environment, so various mitigation strategies are exercised to make them safer, minimize their use, and reduce their unintended environment effects. One strategy that may help achieve these goals relies on the unique properties of chirality or molecular asymmetry. Some common terms related to chirality are defined in Table 1.

  4. Chiral Symmetry Breaking from Center Vortices

    CERN Document Server

    Höllwieser, Roman; Schweigler, Thomas; Heller, Urs M

    2014-01-01

    We analyze the creation of near-zero modes from would-be zero modes of various topological charge contributions from classical center vortices in SU(2) lattice gauge theory. We show that colorful spherical vortex and instanton configurations have very similar Dirac eigenmodes and also vortex intersections are able to give rise to a finite density of near-zero modes, leading to chiral symmetry breaking via the Banks-Casher formula. We discuss the influence of the magnetic vortex fluxes on quarks and how center vortices may break chiral symmetry.

  5. Heavy-tailed chiral random matrix theory

    CERN Document Server

    Kanazawa, Takuya

    2016-01-01

    We study an unconventional chiral random matrix model with a heavy-tailed probabilistic weight. The model is shown to exhibit chiral symmetry breaking with no bilinear condensate, in analogy to the Stern phase of QCD. We solve the model analytically and obtain the microscopic spectral density and the smallest eigenvalue distribution for an arbitrary number of flavors and arbitrary quark masses. Exotic behaviors such as non-decoupling of heavy flavors and a power-law tail of the smallest eigenvalue distribution are illustrated.

  6. Phenomenology of chiral damping in noncentrosymmetric magnets

    KAUST Repository

    Akosa, Collins Ashu

    2016-06-21

    A phenomenology of magnetic chiral damping is proposed in the context of magnetic materials lacking inversion symmetry. We show that the magnetic damping tensor acquires a component linear in magnetization gradient in the form of Lifshitz invariants. We propose different microscopic mechanisms that can produce such a damping in ferromagnetic metals, among which local spin pumping in the presence of an anomalous Hall effect and an effective “s-d” Dzyaloshinskii-Moriya antisymmetric exchange. The implication of this chiral damping in terms of domain-wall motion is investigated in the flow and creep regimes.

  7. The chiral perturbation theory: theoretical aims and experimental perspectives; La theorie des perturbations chirales: enjeux theoriques et perspectives experimentales

    Energy Technology Data Exchange (ETDEWEB)

    Knecht, M. [Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire

    1996-12-31

    Chiral perturbation theory enables to link some hadronic processes at low energy involving {pi},K and {eta} pseudo scalar mesons with some non-perturbative QCD observables which reflect chiral symmetry breaking. The possibilities of investigating the chiral structure of QCD emptiness in several experimental projects within the field of hadronic physics are reviewed 44 refs.

  8. Speciation and gene flow between snails of opposite chirality.

    Directory of Open Access Journals (Sweden)

    Angus Davison

    2005-09-01

    Full Text Available Left-right asymmetry in snails is intriguing because individuals of opposite chirality are either unable to mate or can only mate with difficulty, so could be reproductively isolated from each other. We have therefore investigated chiral evolution in the Japanese land snail genus Euhadra to understand whether changes in chirality have promoted speciation. In particular, we aimed to understand the effect of the maternal inheritance of chirality on reproductive isolation and gene flow. We found that the mitochondrial DNA phylogeny of Euhadra is consistent with a single, relatively ancient evolution of sinistral species and suggests either recent "single-gene speciation" or gene flow between chiral morphs that are unable to mate. To clarify the conditions under which new chiral morphs might evolve and whether single-gene speciation can occur, we developed a mathematical model that is relevant to any maternal-effect gene. The model shows that reproductive character displacement can promote the evolution of new chiral morphs, tending to counteract the positive frequency-dependent selection that would otherwise drive the more common chiral morph to fixation. This therefore suggests a general mechanism as to how chiral variation arises in snails. In populations that contain both chiral morphs, two different situations are then possible. In the first, gene flow is substantial between morphs even without interchiral mating, because of the maternal inheritance of chirality. In the second, reproductive isolation is possible but unstable, and will also lead to gene flow if intrachiral matings occasionally produce offspring with the opposite chirality. Together, the results imply that speciation by chiral reversal is only meaningful in the context of a complex biogeographical process, and so must usually involve other factors. In order to understand the roles of reproductive character displacement and gene flow in the chiral evolution of Euhadra, it will be

  9. HPLC SEPARATION OF CHIRAL ORGANOPHOSPHORUS PESTICIDES ON POLYSACCHARIDE CHIRAL STATIONARY PHASES

    Science.gov (United States)

    High-performance liquid chromatographic separation of the individual enantiomers of 12 organophosphorus pesticides (OPs) were obtained on polysaccharide chiral HPLC columns using an alkane-alcohol mobile phase. The OP pesticides were crotoxyphos, dialifor, dyfonate, fenamiphos, ...

  10. Chiral-field microwave antennas (Chiral microwave near fields for far-field radiation)

    CERN Document Server

    Kamenetskii, E O; Shavit, R

    2015-01-01

    In a single-element structure we obtain a radiation pattern with a squint due to chiral microwave near fields originated from a magnetostatic-mode ferrite disk. At the magnetostatic resonances, one has strong subwavelength localization of energy of microwave radiation. Magnetostatic oscillations in a thin ferrite disk are characterized by unique topological properties: the Poynting-vector vortices and the field helicity. The chiral-topology near fields allow obtaining unique phase structure distribution for far-field microwave radiation.

  11. Intelligent Chiral Sensing Based on Supramolecular and Interfacial Concepts

    Directory of Open Access Journals (Sweden)

    Hironori Izawa

    2010-07-01

    Full Text Available Of the known intelligently-operating systems, the majority can undoubtedly be classed as being of biological origin. One of the notable differences between biological and artificial systems is the important fact that biological materials consist mostly of chiral molecules. While most biochemical processes routinely discriminate chiral molecules, differentiation between chiral molecules in artificial systems is currently one of the challenging subjects in the field of molecular recognition. Therefore, one of the important challenges for intelligent man-made sensors is to prepare a sensing system that can discriminate chiral molecules. Because intermolecular interactions and detection at surfaces are respectively parts of supramolecular chemistry and interfacial science, chiral sensing based on supramolecular and interfacial concepts is a significant topic. In this review, we briefly summarize recent advances in these fields, including supramolecular hosts for color detection on chiral sensing, indicator-displacement assays, kinetic resolution in supramolecular reactions with analyses by mass spectrometry, use of chiral shape-defined polymers, such as dynamic helical polymers, molecular imprinting, thin films on surfaces of devices such as QCM, functional electrodes, FET, and SPR, the combined technique of magnetic resonance imaging and immunoassay, and chiral detection using scanning tunneling microscopy and cantilever technology. In addition, we will discuss novel concepts in recent research including the use of achiral reagents for chiral sensing with NMR, and mechanical control of chiral sensing. The importance of integration of chiral sensing systems with rapidly developing nanotechnology and nanomaterials is also emphasized.

  12. Chirality in nuclei: where do we stand today?

    International Nuclear Information System (INIS)

    The chirality in nuclear rotation was proposed by S. Frauendorf and J. Meng in 1997. Since then, a lot of effort, both from the experimental and theoretical side, has been devoted to explore and understand this rare exotic nuclear phenomenon. Over the years, chiral bands were proposed in several nuclei, mainly, in A ∼ 100 and A ∼ 130 mass regions. But, while looking for more observable experimental fingerprints other than just the energy spectra, the chiral interpretation of bands became doubtful. With the pouring in of more experimental data on absolute B(M1) and B(E2), and innovative theoretical calculations, the chiral character of bands in a few nuclei have been firmly established, and even the transition from chiral vibration to static chirality has been observed. The discovery, progress and recent updates in nuclear chirality, which continues to be a subject of intense discussion, have been reviewed. (author)

  13. Negative reflections of electromagnetic waves in chiral media

    CERN Document Server

    Zhang, C; Cui, Tie Jun; Zhang, Chao

    2006-01-01

    We investigate the reflection properties of electromagnetic/optical waves in isotropic chiral media. When the chiral parameter is strong enough, we show that an unusual \\emph{negative reflection} occurs at the interface of the chiral medium and a perfectly conducting plane, where the incident wave and one of reflected eigenwaves lie in the same side of the boundary normal. Using such a property, we further demonstrate that such a conducting plane can be used for focusing in the strong chiral medium. The related equations under paraxial optics approximation are deduced. In a special case of chiral medium, the chiral nihility, one of the bi-reflections disappears and only single reflected eigenwave exists, which goes exactly opposite to the incident wave. Hence the incident and reflected electric fields will cancel each other to yield a zero total electric field. In another word, any electromagnetic waves entering the chiral nihility with perfectly conducting plane will disappear.

  14. Chiral symmetry breaking and chiral polarization: Tests for finite temperature and many flavors

    Directory of Open Access Journals (Sweden)

    Andrei Alexandru

    2015-02-01

    Full Text Available It was recently conjectured that, in SU(3 gauge theories with fundamental quarks, valence spontaneous chiral symmetry breaking is equivalent to condensation of local dynamical chirality and appearance of chiral polarization scale Λch. Here we consider more general association involving the low-energy layer of chirally polarized modes which, in addition to its width (Λch, is also characterized by volume density of participating modes (Ω and the volume density of total chirality (Ωch. Few possible forms of the correspondence are discussed, paying particular attention to singular cases where Ω emerges as the most versatile characteristic. The notion of finite-volume “order parameter”, capturing the nature of these connections, is proposed. We study the effects of temperature (in Nf=0 QCD and light quarks (in Nf=12, both in the regime of possible symmetry restoration, and find agreement with these ideas. In Nf=0 QCD, results from several volumes indicate that, at the lattice cutoff studied, the deconfinement temperature Tc is strictly smaller than the overlap–valence chiral transition temperature Tch in real Polyakov line vacuum. Somewhat similar intermediate phase (in quark mass is also seen in Nf=12. It is suggested that deconfinement in Nf=0 is related to indefinite convexity of absolute X-distributions.

  15. Role of Chiral symmetry in nuclear physics

    International Nuclear Information System (INIS)

    Spurred by some recent experiments in electron scattering, we reassess the role that chiral symmetry plays in nuclear structure. Though difficult to formulate precisely, some of the ideas put forward many years ago, combined with the recent revival of the Skyrmion picture of the nucleon, are seen to be move relevant now than ever

  16. Effective action for supersymmetrical chiral anomaly

    International Nuclear Information System (INIS)

    It is proved that the consistency conditions of the type of Wess-Zumino conditions are necessary and sufficient for local integrability of supersymmetrical chiral anomaly. The global integrability condition implies discreteness of the coefficient in anomalous action. Explicit formulas for consistent anomalies and corresponding functional depending on superfields of various types are obtained

  17. ISOSPIN BREAKING AND THE CHIRAL CONDENSATE.

    Energy Technology Data Exchange (ETDEWEB)

    CREUTZ, M.

    2005-07-25

    With two degenerate quarks, the chiral condensate exhibits a jump as the quark masses pass through zero. I discuss how this single transition splits into two Ising like transitions when the quarks are made non-degenerate. The order parameter is the expectation of the neutral pion field. The transitions represent long distance coherent phenomena occurring without the Dirac operator having vanishingly small eigenvalues.

  18. Chiral electron transport in CVD bilayer graphene

    Science.gov (United States)

    Lee, Kyunghoon; Eo, Yun Suk; Kurdak, Cagliyan; Zhong, Zhaohui

    2014-03-01

    Charge carriers in bilayer graphene have a parabolic energy spectrum. Due to this band structure they are massive quasiparticles having a finite density of state at zero energy like other non-relativistic charge carriers in conventional two dimensional materials. However, they are massive Dirac fermions which have a chiral nature similar to the case of massless Dirac fermions in single layer graphene. Coupling of pseudospin and motion of charge carrier via chirality can result in dramatic consequence for transport in bipolar regime like Klein tunneling, Fabry-Perot interference, collimation of charge carrier, Veslago lens, etc. However, little attention has been paid to chiral dependent electron transport in bilayer graphene. Here we study these properties by probing phase coherent transport behavior in CVD bilayer graphene devices with sub-200nm channel length. Complex Fabry-Perot interference patterns are observed in resonant cavities defined by local gating. By applying Fourier analysis technique, we successfully analyze and identify the origin of each individual interference pattern in bipolar and monopolar regime. Our initial results also hint at the observation of cloaking of electronic states against chiral electrons in bilayer graphene.

  19. Crystal Chirality Selected by Mutual Antagonism

    Science.gov (United States)

    Yukio Saito,; Hiroyuki Hyuga,

    2010-08-01

    To explore the mechanism of chiral symmetry breaking in a process of crystal growth under grinding, we propose a simple irreversible growth model of a lattice-gas with four possible states on a site: occupied by an achiral molecule A, or by a chiral enantiomer R or S, or empty. After two A molecules on neighboring sites form a chiral dimer R2 or S2, clusters grow by incorporating A’s at cluster periphery, irreversibly. Only the grinding recycles products R or S back to A. It is then demonstrated in kinetic Monte Carlo (KMC) simulations that chirality selection takes place in the presence of the grinding. The cause for this realization is attributed to mutual antagonistic inhibition: that is, clusters of opposite enantiomeric types are brought into contact through stirring, and they block crystallization sites on cluster peripheries each other. The density evolution obtained by time integration of the rate equations with this antagonistic inhibition fits well with results of KMC simulations.

  20. Cranking the chiral soliton bag model

    Energy Technology Data Exchange (ETDEWEB)

    Stern, J.; Bourenane, M.; Clement, G.

    1988-10-01

    The nucleon-delta mass difference is computed in the chiral soliton bag model with soft confinement of gluons by the cranking method. The resulting value of the effective strong fine structure constant is ..cap alpha../sub s/ approx. 0.7.

  1. Chiral Fermi liquid description of nuclear matter

    International Nuclear Information System (INIS)

    We employ Landau's theory of normal Fermi liquids to study the bulk properties of nuclear matter with high-precision two- and three-nucleon interactions derived within the framework of chiral effective field theory. The L=0,1 Landau parameters, characterizing the isotropic and p-wave interaction between two quasiparticles on the Fermi surface, are computed to second order in many-body perturbation theory (MBPT) with chiral and low-momentum two-nucleon forces. Already at this order a number of observables are well described in the theory, including the nuclear isospin asymmetry energy, the quasiparticle effective mass and the spin-isospin response. An adequate description of the nuclear compression modulus (encoded in the Landau parameter F0) requires the inclusion of the leading-order (N2LO) chiral three-nucleon force, which we include to first order in MBPT. The remaining L=0 Landau parameters receive only small corrections from the chiral three-nucleon force, and the L=1 parameters are all reduced, resulting in an effective interaction of apparent short range. We then employ renormalization group techniques to study the scale dependence of the quasiparticle interaction, which allows for an estimation of theoretical uncertainties.

  2. On chiral symmetry breaking, topology and confinement

    Energy Technology Data Exchange (ETDEWEB)

    Shuryak, Edward

    2014-08-15

    We start with the relation between the chiral symmetry breaking and gauge field topology. New lattice results further enhance the notion of Zero Mode Zone, a very narrow strip of states with quasizero Dirac eigenvalues. Then we move to the issue of “origin of mass” and Brown–Rho scaling: a number of empirical facts contradicts to the idea that masses of quarks and such hadrons as ρ,N decrease near T{sub c}. We argue that while at T=0 the main contribution to the effective quark mass is chirally odd m{sub χ/}, near T{sub c} it rotates to chirally-even component m{sub χ}, because “infinite clusters” of topological solitons gets split into finite ones. Recent progress in understanding of topology require introduction of nonzero holonomy 〈A{sub 0}〉≠0, which splits instantons into N{sub c} (anti)selfdual “instanton–dyons”. Qualitative progress, as well as first numerical studies of the dyon ensemble are reported. New connections between chiral symmetry breaking and confinement are recently understood, since instanton–dyons generate holonomy potential with a minimum at confining value, if the ensemble is dense enough.

  3. Electroweak Chiral Lagrangian for Neutral Higgs Boson

    Institute of Scientific and Technical Information of China (English)

    WANG Shun-Zhi; WANG Qing

    2008-01-01

    A neutral Higgs boson is added into the traditional electroweak chiral Lagrangian by writing down all possible high dimension operators. The matter part of the Lagrangian is investigated in detail. We find that if Higgs field dependence of Yukawa couplings can be factorized out, there will be no flavour changing neutral couplings; neutral Higgs can induce coupling between light and heavy neutrinos.

  4. On the Chiral imbalance and Weibel Instabilities

    CERN Document Server

    Kumar, Avdhesh; Kaw, Predhiman K

    2016-01-01

    We study the chiral-imbalance and the Weibel instabilities in presence of the quantum anomaly using the Berry-curvature modified kinetic equation. We argue that in many realistic situations, e.g. relativistic heavy-ion collisions, both the instabilities can occur simultaneously. The Weibel instability depends on the momentum anisotropy parameter $\\xi$ and the angle ($\\theta_n$) between the propagation vector and the anisotropy direction. It has maximum growth rate at $\\theta_n=0$ while $\\theta_n=\\pi/2$ corresponds to a damping. On the other hand the pure chiral-imbalance instability occurs in an isotropic plasma and depends on difference between the chiral chemical potentials of right and left-handed particles. It is shown that when $\\theta_n=0$, only for a very small values of the anisotropic parameter $\\xi\\sim \\xi_c$, growth rates of the both instabilities are comparable. For the cases $\\xi_c<\\xi\\ll1$, $\\xi\\approx 1$ or $\\xi \\geq 1$ at $\\theta_n=0$, the Weibel modes dominate over the chiral-imbalance ins...

  5. Anomalous Hall Effect for chiral fermions

    CERN Document Server

    Zhang, P -M

    2014-01-01

    Semiclassical chiral fermions manifest the anomalous spin-Hall effect: when put into a pure electric field, they suffer a side jump, analogous to what happens to their massive counterparts in non-commutative mechanics. The transverse shift is consistent with the conservation of the angular momentum. In a pure magnetic field a cork-screw-like, spiraling motion is found.

  6. Efficient Biocatalytic Synthesis of Chiral Chemicals.

    Science.gov (United States)

    Zhang, Zhi-Jun; Pan, Jiang; Ma, Bao-Di; Xu, Jian-He

    2016-01-01

    Chiral chemicals are a group of important chiral synthons for the synthesis of a series of pharmaceuticals, agrochemicals, and fine chemicals. In past decades, a number of biocatalytic approaches have been developed for the green and effective synthesis of various chiral chemicals. However, the practical application of these biocatalytic processes is still hindered by the lack of highly efficient and robust biocatalysts, which usually results in the low volumetric productivity and high cost of the bioprocesses. Further step forward of biocatalysis in industrial application strongly requires the development of versatile and highly efficient biocatalysts, aiming to increase the process efficiency and facilitate the downstream processing. Recently, the fast growth of genome sequences in the database in post-genomic era offers great opportunities for accessing numerous biocatalysts with practical application potential, and the so-called genome mining approach provides time-effective and highly specific strategy for the fast identification of target enzymes with desired properties and outperforms the traditional screening of soil samples for microbial enzyme producers of interest. A number of biocatalytic processes with industrial application potential were developed thereafter. Further development of protein engineering strategies, process optimization, and cooperative work between biologists, organic chemists, and engineers is expected to make biocatalysis technology the first choice approach for the eco-friendly, highly efficient, and cost-effective synthesis of chiral chemicals in the near future. PMID:25537446

  7. Nucleon Structure Functions from a Chiral Soliton

    OpenAIRE

    Weigel, H.(Physics Department, Stellenbosch University, Matieland 7602, South Africa); Gamberg, L.(Department of Physics, Penn State University-Berks, Reading, PA, 19610, U.S.A.); Reinhardt, H.

    1996-01-01

    Nucleon structure functions are studied within the chiral soliton approach to the bosonized Nambu-Jona-Lasinio model. The valence quark approximation is employed which is justified for moderate constituent quark masses ($\\sim$ 400 MeV) as the contribution of the valence quark level dominates the predictions of nucleon properties. As examples the unpolarized structure functions for the ${\

  8. Chiral damping of magnetic domain walls

    KAUST Repository

    Jué, Emilie

    2015-12-21

    Structural symmetry breaking in magnetic materials is responsible for the existence of multiferroics1, current-induced spin–orbit torques2, 3, 4, 5, 6, 7 and some topological magnetic structures8, 9, 10, 11, 12. In this Letter we report that the structural inversion asymmetry (SIA) gives rise to a chiral damping mechanism, which is evidenced by measuring the field-driven domain-wall (DW) motion in perpendicularly magnetized asymmetric Pt/Co/Pt trilayers. The DW dynamics associated with the chiral damping and those with Dzyaloshinskii–Moriya interaction (DMI) exhibit identical spatial symmetry13, 14, 15, 16, 17, 18, 19. However, both scenarios are differentiated by their time reversal properties: whereas DMI is a conservative effect that can be modelled by an effective field, the chiral damping is purely dissipative and has no influence on the equilibrium magnetic texture. When the DW motion is modulated by an in-plane magnetic field, it reveals the structure of the internal fields experienced by the DWs, allowing one to distinguish the physical mechanism. The chiral damping enriches the spectrum of physical phenomena engendered by the SIA, and is essential for conceiving DW and skyrmion devices owing to its coexistence with DMI (ref. 20).

  9. Weighted power counting and chiral dimensional regularization

    Science.gov (United States)

    Anselmi, Damiano

    2014-06-01

    We define a modified dimensional-regularization technique that overcomes several difficulties of the ordinary technique, and is specially designed to work efficiently in chiral and parity violating quantum field theories, in arbitrary dimensions greater than 2. When the dimension of spacetime is continued to complex values, spinors, vectors and tensors keep the components they have in the physical dimension; therefore, the γ matrices are the standard ones. Propagators are regularized with the help of evanescent higher-derivative kinetic terms, which are of the Majorana type in the case of chiral fermions. If the new terms are organized in a clever way, weighted power counting provides an efficient control on the renormalization of the theory, and allows us to show that the resulting chiral dimensional regularization is consistent to all orders. The new technique considerably simplifies the proofs of properties that hold to all orders, and makes them suitable to be generalized to wider classes of models. Typical examples are the renormalizability of chiral gauge theories and the Adler-Bardeen theorem. The difficulty of explicit computations, on the other hand, may increase.

  10. Chiral symmetry and parametrization of scalar resonances

    CERN Document Server

    Arantes, L O

    2005-01-01

    The linear $\\s$-model is used to study the effects of chiral symmetry in unitarized amplitudes incorporating scalar resonances. When just a single resonance is present, we show that the iteration of a chiral tree amplitude by means of regularized two-pion loops preserves the smallness of $\\p\\p$ interaction at low energies and estimate the importance of pion off-shell contributions. The inclusion of a second resonance is performed by means of a chiral extension of the linear $\\s$-model lagrangian. The new $\\p\\p$ ampitude at tree level complies with low-energy theorems, depends on a mixing angle and has a zero for a given energy between the resonance masses. The unitarization of this amplitude by means of two-pion loops preserves both its chiral low energy behavior and the position of this zero confirming, in a lagrangian framework, conclusions drawn previously by T\\"ornqvist. Finally, we approximate and generalize our results and give a friendly expression that can be used in the parametrization of $N$ coupled...

  11. CHIRAL SWITCH- AN EMERGING STRATEGY IN THERAPEUTICS

    Directory of Open Access Journals (Sweden)

    SUSHIL SHARMA

    2014-03-01

    Full Text Available During the last decade, drug chirality, more specifically the use of single enantiomers versus racemic mixtures has been in the forefront of discussions in scientific forums. This is because the left and right handed twins of a molecule behave quite differently from each other in a biological environment. This can frequently lead to an improvement in pharmacological and therapeutic profile of the molecule/drug. This understanding of the significance of stereochemistry coupled with advances in chemical technologies and further nudged by regulatory requirements has helped the increase in the development of individual isomers at the expense of racemic mixtures. Apart from the development of novel stereo-selective compounds, a number of racemates have been re-evaluated as potential single enantiomer agents with the possibility of an improved pharmacological/ therapeutic profile. These have been termed as Chiral Switches and have resulted in the re-birth of a number of agents as single enantiomers and have provided significant improvements over the racemic drug. Economic considerations are also playing a part with pharmaceutical companies increasingly using chiral switching as a marketing strategy to increase the patent longevity and profitability period of a drug. However, not all these switches have resulted in therapeutic superiority and in many instances, unpredicted adverse reactions have resulted. Before a switch to clinical use of single enantiomers is made, physicians should satisfy themselves from evidence based on well-conducted clinical trials that the chiral switch is cost-effective and improves the outcomes for patients.

  12. Magnetic properties in the inhomogeneous chiral phase

    CERN Document Server

    Yoshiike, Ryo; Tatsumi, Toshitaka

    2016-01-01

    We investigate the magnetic properties of quark matter in the inhomogeneous chiral phase, where both scalar and pseudoscalar condensates spatially modulate. The energy spectrum of the lowest Landau level becomes asymmetric about zero in the external magnetic field, and gives rise to the remarkably magnetic properties: quark matter has a spontaneous magnetization, while the magnetic susceptibility does not diverge on the critical point.

  13. Chiral effective field theory and nuclear forces

    CERN Document Server

    Machleidt, R

    2011-01-01

    We review how nuclear forces emerge from low-energy QCD via chiral effective field theory. The presentation is accessible to the non-specialist. At the same time, we also provide considerable detailed information (mostly in appendices) for the benefit of researchers who wish to start working in this field.

  14. Chiral separation and twin-beam photonics

    Science.gov (United States)

    Bradshaw, David S.; Andrews, David L.

    2016-03-01

    It is well-known that, in a homogeneous fluid medium, most optical means that afford discrimination between molecules of opposite handedness are intrinsically weak effects. The reason is simple: the wide variety of origins for differential response commonly feature real or virtual electronic transitions that break a parity condition. Despite being electric dipole allowed, they manifest the chirality of the material in which they occur by breaking a selection rule that would otherwise preclude the simultaneous involvement of magnetic dipole or electric quadrupole forms of coupling. Although the latter are typically weaker than electric dipole effects by several orders of magnitude, it is the involvement of these weak forms of interaction that are responsible for chiral sensitivity. There have been a number of attempts to cleverly exploit novel optical configurations to enhance the relative magnitude - and hence potentially the efficiency - of chiral discrimination. The prospect of success in any such venture is enticing, because of the huge impact that such an advance might be expected to have in the health, food and medical sectors. Some of these proposals have utilized mirror reflection, and others surface plasmon coupling, or optical binding methods. Several recent works in the literature have drawn attention to a further possibility: the deployment of optical beam interference as a means to achieve chiral separations of sizeable extent. In this paper the underlying theory is fully developed to identify the true scope and limitations of such an approach.

  15. Leading chiral logarithms for the nucleon mass

    Energy Technology Data Exchange (ETDEWEB)

    Vladimirov, Alexey A.; Bijnens, Johan [Department of Astronomy and Theoretical Physics, Lund University, Sölvegatan 14A, SE 223 62 Lund (Sweden)

    2016-01-22

    We give a short introduction to the calculation of the leading chiral logarithms, and present the results of the recent evaluation of the LLog series for the nucleon mass within the heavy baryon theory. The presented results are the first example of LLog calculation in the nucleon ChPT. We also discuss some regularities observed in the leading logarithmical series for nucleon mass.

  16. A Note on Ward's Chiral Model

    OpenAIRE

    Ioannidou, Theodora; Zakrzewski, Wojtek

    1998-01-01

    A one parameter generalization of Ward's chiral model in 2+1 dimensions is given. Like the original model the present one is integrable and possesses a positive-definite and conserved energy and $y$-momentum. The details of the scattering depend on the value of the parameter of the generalisation.

  17. Chiral damping of magnetic domain walls.

    Science.gov (United States)

    Jué, Emilie; Safeer, C K; Drouard, Marc; Lopez, Alexandre; Balint, Paul; Buda-Prejbeanu, Liliana; Boulle, Olivier; Auffret, Stephane; Schuhl, Alain; Manchon, Aurelien; Miron, Ioan Mihai; Gaudin, Gilles

    2016-03-01

    Structural symmetry breaking in magnetic materials is responsible for the existence of multiferroics, current-induced spin-orbit torques and some topological magnetic structures. In this Letter we report that the structural inversion asymmetry (SIA) gives rise to a chiral damping mechanism, which is evidenced by measuring the field-driven domain-wall (DW) motion in perpendicularly magnetized asymmetric Pt/Co/Pt trilayers. The DW dynamics associated with the chiral damping and those with Dzyaloshinskii-Moriya interaction (DMI) exhibit identical spatial symmetry. However, both scenarios are differentiated by their time reversal properties: whereas DMI is a conservative effect that can be modelled by an effective field, the chiral damping is purely dissipative and has no influence on the equilibrium magnetic texture. When the DW motion is modulated by an in-plane magnetic field, it reveals the structure of the internal fields experienced by the DWs, allowing one to distinguish the physical mechanism. The chiral damping enriches the spectrum of physical phenomena engendered by the SIA, and is essential for conceiving DW and skyrmion devices owing to its coexistence with DMI (ref. ). PMID:26689141

  18. Role of pseudoephedrine as chiral auxiliary in the "acetate-type" aldol reaction with chiral aldehydes; asymmetric synthesis of highly functionalized chiral building blocks.

    Science.gov (United States)

    Ocejo, Marta; Carrillo, Luisa; Vicario, Jose L; Badía, Dolores; Reyes, Efraim

    2011-01-21

    We have studied in depth the aldol reaction between acetamide enolates and chiral α-heterosubstituted aldehydes using pseudoephedrine as chiral auxiliary under double stereodifferentiation conditions, showing that high diastereoselectivities can only be achieved under the matched combination of reagents and provided that the α-heteroatom-containing substituent of the chiral aldehyde is conveniently protected. Moreover, the obtained highly functionalized aldols have been employed as very useful starting materials for the stereocontrolled preparation of other interesting compounds and chiral building blocks such as pyrrolidines, indolizidines, and densely functionalized β-hydroxy and β-amino ketones using simple and high-yielding methodologies. PMID:21188970

  19. Effect of molecular structure of tartrates on chiral recognition of tartrate-boric acid complex chiral selectors in chiral microemulsion electrokinetic chromatography.

    Science.gov (United States)

    Hu, Shao-Qiang; Chen, Yong-Lei; Zhu, Hua-Dong; Shi, Hai-Jun; Yan, Na; Chen, Xing-Guo

    2010-08-20

    Eight l-tartrates and a d-tartrate with different alcohol moieties were used as chiral oils to prepare chiral microemulsions, which were utilized in conjunction with borate buffer to separate the enantiomers of beta-blockers or structurally related compounds by the chiral microemulsion electrokinetic chromatography (MEEKC) method. Among them, six were found to have a relatively good chiral separation performance and their chiral recognition effect in terms of both enantioselectivity and resolution increases linearly with the number of carbon atoms in the alkyl group of alcohol moiety. The tartrates containing alkyl groups of different structures but the same number of carbon atoms, i.e. one of straight chain and one of branched chain, provide similar enantioseparations. The trend was elucidated according to the changes in the difference of the steric matching between the molecules of two enantiomers and chiral selector. Furthermore, it was demonstrated for the first time that a water insoluble solid compound, di-i-butyl l-tartrate (mp. 73.5 degrees C), can be used as an oil to prepare a stable microemulsion to be used in the chiral MEEKC successfully. And a critical effect of the microemulsion for chiral separation, which has never been reported before, was found in this experiment, namely providing a hydrophobic environment to strengthen the interactions between the chiral selector and enantiomers. PMID:20638068

  20. Chiral Sensitivity in Electron-Molecule Interactions

    Science.gov (United States)

    Dreiling, Joan

    2015-09-01

    All molecular forms of life possess a chiral asymmetry, with amino acids and sugars found respectively in L- and D-enantiomers only. The primordial origin of this enantiomeric excess is unknown. One possible explanation is given by the Vester- Ulbricht hypothesis, which suggests that left-handed electrons present in beta-radiation, produced by parity-violating weak decays, interacted with biological precursors and preferentially destroyed one of the two enantiomers. Experimental tests of this idea have thus far yielded inconclusive results. We show direct evidence for chirally-dependent bond breaking through a dissociative electron attachment (DEA) reaction when spin-polarized electrons are incident on gas-phase chiral molecules. This provides unambiguous evidence for a well-defined, chirally-sensitive destructive molecular process and, as such, circumstantial evidence for the Vester-Ulbricht hypothesis. I will also present the results of our systematic study of the DEA asymmetry for different chiral halocamphor molecules. Three halocamphor molecules were investigated: 3-bromocamphor (C10H15BrO), 3-iodocamphor(C10H15IO), and 10-iodocamphor. The DEA asymmetries collected for bromocamphor and iodocamphor are qualitatively different, suggesting that the atomic number of the heaviest atom in the molecule plays a crucial role in the asymmetric interactions. The DEA asymmetry data for 3- and 10-iodocamphor have the same qualitative behavior, but the 10-iodocamphor asymmetry is about twice as large at the lowest energies investigated, so the location of the heavy atom in the camphor molecule also affects the asymmetries. This work was performed at the University of Nebraska-Lincoln. This project is funded by NSF Grant PHY-1206067.

  1. Baryons in the chiral regime

    Energy Technology Data Exchange (ETDEWEB)

    Knippschild, Bastian

    2012-03-05

    Quantum Chromodynamics (QCD) is the theory of strong interactions, one of the four fundamental forces in our Universe. It describes the interaction of gluons and quarks which build up hadrons like protons and neutrons. Most of the visible matter in our universe is made of protons and neutrons. Hence, we are interested in their fundamental properties like their masses, their distribution of charge and their shape. The only known theoretical, non-perturbative and ab initio method to investigate hadron properties at low energies is lattice Quantum Chromodynamics (lattice QCD). However, up-to-date simulations (especially for baryonic quantities) do not achieve the accuracy of experiments. In fact, current simulations do not even reproduce the experimental values for the form factors. The question arises wether these deviations can be explained by systematic effects in lattice QCD simulations. This thesis is about the computation of nucleon form factors and other hadronic quantities from lattice QCD. So called Wilson fermions are used and the u- and d-quarks are treated fully dynamically. The simulations were performed using gauge ensembles with a range of lattice spacings, volumes and pion masses. First of all, the lattice spacing was set to be able to make contact between the lattice results and their experimental complement and to be able to perform a continuum extrapolation. The light quark mass has been computed and found to be m{sub ud}{sup MS}(2 GeV)=3.03(17)(38) MeV. This value is in good agreement with values from experiments and other lattice determinations. Electro-magnetic and axial form factors of the nucleon have been calculated. From these form factors the nucleon radii and the coupling constants were computed. The different ensembles enabled us to investigate systematically the dependence of these quantities on the volume, the lattice spacing and the pion mass. Finally we perform a continuum extrapolation and chiral extrapolations to the physical point

  2. Memorized chiral arrangement of gemini surfactant assemblies in nanometric hybrid organic-silica helices.

    Science.gov (United States)

    Ryu, Naoya; Okazaki, Yutaka; Hirai, Kana; Takafuji, Makoto; Nagaoka, Shoji; Pouget, Emilie; Ihara, Hirotaka; Oda, Reiko

    2016-04-30

    Hybrid nanohelices were obtained from silicification of self-assemblies of gemini surfactants with tartrate counterions. The chiral arrangement of these non-chiral gemini surfactants was preserved in the silica matrix even after the counterion exchange for a non-chiral bromide, and was capable of inducing the chiral organisation of a non-chiral dye, methyl orange. PMID:26961377

  3. Molecular-Level Design of Heterogeneous Chiral Catalysis

    International Nuclear Information System (INIS)

    The following is a proposal to continue our multi-institutional research on heterogeneous chiral catalysis. Our team combines the use of surface-sensitive analytical techniques for the characterization of model systems with quantum and statistical mechanical calculations to interpret experimental data and guide the design of future research. Our investigation focuses on the interrelation among the three main mechanisms by which enantioselectivity can be bestowed to heterogeneous catalysts, namely: (1) by templating chirality via the adsorption of chiral supramolecular assemblies, (2) by using chiral modifiers capable of forming chiral complexes with the reactant and force enantioselective surface reactions, and (3) by forming naturally chiral surfaces using imprinting chiral agents. Individually, the members of our team are leaders in these various aspects of chiral catalysis, but the present program provides the vehicle to generate and exploit the synergies necessary to address the problem in a comprehensive manner. Our initial work has advanced the methodology needed for these studies, including an enantioselective titration procedure to identify surface chiral sites, infrared spectroscopy in situ at the interface between gases or liquids and solids to mimic realistic catalytic conditions, and DFT and Monte Carlo algorithms to simulate and understand chirality on surfaces. The next step, to be funded by the monies requested in this proposal, is to apply those methods to specific problems in chiral catalysis, including the identification of the requirements for the formation of supramolecular surface structures with enantioselective behavior, the search for better molecules to probe the chiral nature of the modified surfaces, the exploration of the transition from supramolecular to one-to-one chiral modification, the correlation of the adsorption characteristics of one-to-one chiral modifiers with their physical properties, in particular with their configuration

  4. Molecular-Level Design of Heterogeneous Chiral Catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Francisco Zaera

    2012-03-21

    The following is a proposal to continue our multi-institutional research on heterogeneous chiral catalysis. Our team combines the use of surface-sensitive analytical techniques for the characterization of model systems with quantum and statistical mechanical calculations to interpret experimental data and guide the design of future research. Our investigation focuses on the interrelation among the three main mechanisms by which enantioselectivity can be bestowed to heterogeneous catalysts, namely: (1) by templating chirality via the adsorption of chiral supramolecular assemblies, (2) by using chiral modifiers capable of forming chiral complexes with the reactant and force enantioselective surface reactions, and (3) by forming naturally chiral surfaces using imprinting chiral agents. Individually, the members of our team are leaders in these various aspects of chiral catalysis, but the present program provides the vehicle to generate and exploit the synergies necessary to address the problem in a comprehensive manner. Our initial work has advanced the methodology needed for these studies, including an enantioselective titration procedure to identify surface chiral sites, infrared spectroscopy in situ at the interface between gases or liquids and solids to mimic realistic catalytic conditions, and DFT and Monte Carlo algorithms to simulate and understand chirality on surfaces. The next step, to be funded by the monies requested in this proposal, is to apply those methods to specific problems in chiral catalysis, including the identification of the requirements for the formation of supramolecular surface structures with enantioselective behavior, the search for better molecules to probe the chiral nature of the modified surfaces, the exploration of the transition from supramolecular to one-to-one chiral modification, the correlation of the adsorption characteristics of one-to-one chiral modifiers with their physical properties, in particular with their configuration

  5. Chiral assembly of weakly curled hard rods: Effect of steric chirality and polarity

    Energy Technology Data Exchange (ETDEWEB)

    Wensink, H. H., E-mail: wensink@lps.u-psud.fr; Morales-Anda, L. [Laboratoire de Physique des Solides–UMR 8502, Université Paris-Sud & CNRS, 91405 Orsay (France)

    2015-10-14

    We theoretically investigate the pitch of lyotropic cholesteric phases composed of slender rods with steric chirality transmitted via a weak helical deformation of the backbone. In this limit, the model is amenable to analytical treatment within Onsager theory and a closed expression for the pitch versus concentration and helical shape can be derived. Within the same framework, we also briefly review the possibility of alternative types of chiral order, such as twist-bend or screw-like nematic phases, finding that cholesteric order dominates for weakly helical distortions. While long-ranged or “soft” chiral forces usually lead to a pitch decreasing linearly with concentration, steric chirality leads to a much steeper decrease of quadratic nature. This reveals a subtle link between the range of chiral intermolecular interaction and the pitch sensitivity with concentration. A much richer dependence on the thermodynamic state is revealed for polar helices where parallel and anti-parallel pair alignments along the local director are no longer equivalent. It is found that weak temperature variations may lead to dramatic changes in the pitch, despite the lyotropic nature of the assembly.

  6. Enhanced Electromagnetic Chirality by Locally Excited Surface Plasmon Polaritons

    CERN Document Server

    Alizadeh, M H

    2015-01-01

    The possibility to enhance chiral light-matter interactions through plasmonic nanostructures provides entirely new opportunities for greatly improving the detection limits of chiroptical spectroscopies down to the single molecule level. The most pronounced of these chiral interactions occur in the ultraviolet (UV) range of the electromagnetic spectrum, which is difficult to access with conventional localized plasmon resonance based sensors. Although Surface Plasmon Polaritons (SPPs) on noble metal films can sustain resonances in the desired spectral range, their transverse magnetic nature has been an obstacle for enhancing chiroptical effects. Here we demonstrate, both analytically and numerically, that SPPs excited by near-field sources can exhibit rich and non-trivial chiral characteristics. In particular, we show that the excitation of SPPs by a chiral source not only results in a locally enhanced optical chirality but also achieves manifold enhancement of net optical chirality. Our finding that SPPs facil...

  7. Chiral solitons in a coupled double Peierls chain.

    Science.gov (United States)

    Cheon, Sangmo; Kim, Tae-Hwan; Lee, Sung-Hoon; Yeom, Han Woong

    2015-10-01

    Chiral edge states are the hallmark of two- and three-dimensional topological materials, but their one-dimensional (1D) analog has not yet been found. We report that the 1D topological edge states, solitons, of the charge density wave system of indium atomic wires self-assembled on a silicon surface have chirality. The system is described by a coupled double Peierls-dimerized atomic chain, where the interchain coupling induces dynamical sublattice symmetry breaking. This changes its topological symmetry from Z₂× Z₂to Z₄ and endows solitons with a chiral degree of freedom. Chiral solitons can produce quantized charge transport across the chain that is topologically protected and controllable by the soliton's chirality. Individual right- and left-chiral solitons in indium wires are directly identified by scanning tunneling microscopy. PMID:26450206

  8. Formation of chiral branched nanowires by the Eshelby Twist.

    Science.gov (United States)

    Zhu, Jia; Peng, Hailin; Marshall, A F; Barnett, D M; Nix, W D; Cui, Yi

    2008-08-01

    Manipulating the morphology of inorganic nanostructures, such as their chirality and branching structure, has been actively pursued as a means of controlling their electrical, optical and mechanical properties. Notable examples of chiral inorganic nanostructures include carbon nanotubes, gold multishell nanowires, mesoporous nanowires and helical nanowires. Branched nanostructures have also been studied and been shown to have interesting properties for energy harvesting and nanoelectronics. Combining both chiral and branching motifs into nanostructures might provide new materials properties. Here we show a chiral branched PbSe nanowire structure, which is formed by a vapour-liquid-solid branching from a central nanowire with an axial screw dislocation. The chirality is caused by the elastic strain of the axial screw dislocation, which produces a corresponding Eshelby Twist in the nanowires. In addition to opening up new opportunities for tailoring the properties of nanomaterials, these chiral branched nanowires also provide a direct visualization of the Eshelby Twist. PMID:18685634

  9. The Chiral Magnetic Effect and Anomaly-Induced Transport

    CERN Document Server

    Kharzeev, Dmitri E

    2013-01-01

    The Chiral Magnetic Effect (CME) is the phenomenon of electric charge separation along the external magnetic field that is induced by the chirality imbalance. The CME is a macroscopic quantum effect - it is a manifestation of the chiral anomaly creating a collective motion in Dirac sea. Because the chirality imbalance is related to the global topology of gauge fields, the CME current is topologically protected and hence non-dissipative even in the presence of strong interactions. As a result, the CME and related quantum phenomena affect the hydrodynamical and transport behavior of systems possessing chiral fermions, from the quark-gluon plasma to chiral materials. The goal of the present review is to provide an elementary introduction into the main ideas underlying the physics of CME, a historical perspective, and a guide to the rapidly growing literature on this topic.

  10. Detecting chirality in molecules by linearly polarized laser fields

    CERN Document Server

    Yachmenev, Andrey

    2016-01-01

    A new scheme for enantiomer differentiation of chiral molecules using a pair of linearly polarized intense ultrashort laser pulses with skewed mutual polarization is presented. The technique relies on the fact that the off-diagonal anisotropic contributions to the electric polarizability tensor for two enantiomers have different signs. Exploiting this property, we are able to excite a coherent unidirectional rotation of two enantiomers with a {\\pi} phase difference in the molecular electric dipole moment. The approach is robust and suitable for relatively high temperatures of molecular samples, making it applicable for selective chiral analysis of mixtures, and to chiral molecules with low barriers between enantiomers. As an illustration, we present nanosecond laser-driven dynamics of a tetratomic non-rigid chiral molecule with short-lived chirality. The ultrafast time scale of the proposed technique is well suited to study parity violation in molecular systems in short-lived chiral states.

  11. Detecting Chirality in Molecules by Linearly Polarized Laser Fields

    Science.gov (United States)

    Yachmenev, Andrey; Yurchenko, Sergei N.

    2016-07-01

    A new scheme for enantiomer differentiation of chiral molecules using a pair of linearly polarized intense ultrashort laser pulses with skewed mutual polarization is presented. The technique relies on the fact that the off-diagonal anisotropic contributions to the electric polarizability tensor for two enantiomers have different signs. Exploiting this property, we are able to excite a coherent unidirectional rotation of two enantiomers with a π phase difference in the molecular electric dipole moment. The approach is robust and suitable for relatively high temperatures of molecular samples, making it applicable for selective chiral analysis of mixtures, and to chiral molecules with low barriers between enantiomers. As an illustration, we present nanosecond laser-driven dynamics of a tetratomic nonrigid chiral molecule with short-lived chirality. The ultrafast time scale of the proposed technique is well suited to study parity violation in molecular systems in short-lived chiral states.

  12. Chiral medium produced by parallel electric and magnetic fields

    CERN Document Server

    Ruggieri, Marco; Chernodub, Maxim

    2016-01-01

    We compute (pseudo)critical temperature, $T_c$, of chiral symmetry restoration for quark matter in the background of parallel electric and magnetic fields. This field configuration leads to the production of a chiral medium on a time scale $\\tau$, characterized by a nonvanishing value of the chiral density that equilibrates due to microscopic processes in the thermal bath. We estimate the relaxation time $\\tau$ to be about $\\approx 0.1-1$ fm/c around the chiral crossover; then we compute the effect of the fields and of the chiral medium on~$T_c$. We find $T_c$ to be lowered by the external fields in the chiral medium.

  13. Chiral spiral induced by a strong magnetic field

    CERN Document Server

    Abuki, H

    2016-01-01

    We study the modification of the chiral phase structure of QCD due to an external magnetic field. We first demonstrate how the effect of magnetic field can systematically be incorporated into a generalized Ginzburg-Landau framework. We then analyze the phase structure in the vicinity of the chiral critical point. In the chiral limit, the effect is found to be so drastic that it totally washes the tricritical point out of the phase diagram, bringing the continent for the chiral spiral. This is the case no matter how small is the intensity of the magnetic field. On the other hand, the current quark mass protects the chiral critical point from a weak magnetic field. However the critical point will eventually be covered by the chiral spiral phase as the magnetic field grows.

  14. Emergence of Chirality from Isotropic Interactions of Three Length Scales

    Science.gov (United States)

    Mkhonta, S. K.; Elder, K. R.; Huang, Zhi-Feng

    2016-05-01

    Chirality is known to play a pivotal role in determining material properties and functionalities. However, it remains a great challenge to understand and control the emergence of chirality and the related enantioselective process particularly when the building components of the system are achiral. Here we explore the generic mechanisms driving the formation of two-dimensional chiral structures in systems characterized by isotropic interactions and three competing length scales. We demonstrate that starting from isotropic and rotationally invariant interactions, a variety of chiral ordered patterns and superlattices with anisotropic but achiral units can self-assemble. The mechanisms for selecting specific states are related to the length-scale coupling and the selection of resonant density wave vectors. Sample phase diagrams and chiral elastic properties are identified. These findings provide a viable route for predicting chiral phases and selecting the desired handedness.

  15. Generation of chiral spin state by quantum simulation

    Science.gov (United States)

    Tanamoto, Tetsufumi

    2016-06-01

    Chirality of materials in nature appears when there are asymmetries in their lattice structures or interactions in a certain environment. Recent development of quantum simulation technology has enabled the manipulation of qubits. Accordingly, chirality can be realized intentionally rather than passively observed. Here we theoretically provide simple methods to create a chiral spin state in a spin-1/2 qubit system on a square lattice. First, we show that switching on and off the Heisenberg and X Y interactions produces the chiral interaction directly in the effective Hamiltonian without controlling local fields. Moreover, when initial states of spin qubits are appropriately prepared, we prove that the chirality with desirable phase is dynamically obtained. Finally, even for the case where switching on and off the interactions is infeasible and the interactions are always on, we show that, by preparing an asymmetric initial qubit state, the chirality whose phase is π /2 is dynamically generated.

  16. Nonperturbative Regulator for Chiral Gauge Theories?

    Science.gov (United States)

    Grabowska, Dorota M; Kaplan, David B

    2016-05-27

    We propose a nonperturbative gauge-invariant regulator for d-dimensional chiral gauge theories on the lattice. The method involves simulating domain wall fermions in d+1 dimensions with quantum gauge fields that reside on one d-dimensional surface and are extended into the bulk via gradient flow. The result is a theory of gauged fermions plus mirror fermions, where the mirror fermions couple to the gauge fields via a form factor that becomes exponentially soft with the separation between domain walls. The resultant theory has a local d-dimensional interpretation only if the chiral fermion representation is anomaly free. A physical realization of this construction would imply the existence of mirror fermions in the standard model that are invisible except for interactions induced by vacuum topology, and which could gravitate differently than conventional matter. PMID:27284646

  17. Toy model for two chiral nonets

    CERN Document Server

    Fariborz, A H; Schechter, J; Fariborz, Amir H.; Jora, Renata; Schechter, Joseph

    2005-01-01

    Motivated by the possibility that nonets of scalar mesons might be described as mixtures of "two quark" and "four quark" components, we further study a toy model in which corresponding chiral nonets (containing also the pseudoscalar partners) interact with each other. Although the "two quark" and "four quark" chiral fields transform identically under SU(3)$_L \\times$ SU(3)$_R$ transformations they transform differently under the U(1)$_A$ transformation which essentially counts total (quark + antiquark) content of the mesons. To implement this we formulate an effective Lagrangian which mocks up the U(1)$_A$ behavior of the underlying QCD. We derive generating equations which yield Ward identity type relations based only on the assumed symmetry structure. This is applied to the mass spectrum of the low lying pseudoscalars and scalars. as well as their "excitations". Assuming isotopic spin invariance, it is possible to disentangle the amount of"two quark" vs."four quark" content in the pseudoscalar $\\pi, K ,\\eta...

  18. Lagrangians for Massive Dirac Chiral Superfields

    CERN Document Server

    Jiménez, Enrique

    2015-01-01

    A new off-shell, $ 4D $, $ \\mathcal{N}=1 $ supersymmetric theory, based on massive Dirac superfields and carrying superspin one-half, is offered. In order to obtain the Dirac formalism for fermions, second order derivatives in the propagating component Dirac fields must be absent in the off-shell free Lagrangian. The bosonic sector is encoded in a tensor-spinor field and after studying its form, in the interaction picture, the propagating and auxiliary bosonic fields are identified. Besides the supersymmetric chiral condition, the Dirac superfields are not further constrained. In addition, an interaction super Yukawa potential, formed by Dirac and scalar chiral superfields, is given in terms of their component fields. Finally, in order to treat the case of neutral superparticles, the Majorana condition on the Dirac superfields is imposed.

  19. Oscillating Chiral Tensor Spectrum from Axionic Inflation

    CERN Document Server

    Obata, Ippei

    2016-01-01

    We study the axionic inflation with a modulated potential and examine if the primordial tensor power spectrum exhibits oscillatory feature, which is testable with future space-based gravitational wave experiments such as DECIGO and BBO. In the case of the single-field axion monodromy inflation, it turns out that it is difficult to detect the oscillation in the spectrum due to suppression of the sub-Planckian decay constant of axion. On the other hand, in the case of aligned chromo-natural inflation where the axion is coupled to a SU(2) gauge field, it turns out that the sizable oscillation in the tensor spectrum can occur due to the enhancement of chiral gravitational waves sourced by the gauge field. We expect that this feature will be a new probe to axion phenomenologies in early universe through the chiral gravitational waves.

  20. Mechanically generated surface chirality at the nanoscale.

    Science.gov (United States)

    Ferjani, Sameh; Choi, Yoonseuk; Pendery, Joel; Petschek, Rolfe G; Rosenblatt, Charles

    2010-06-25

    A substrate coated with an achiral polyimide alignment layer was scribed bidirectionally with the stylus of an atomic force microscope to create an easy axis for liquid crystal orientation. The resulting noncentrosymmetric topography resulted in a chiral surface that manifests itself at the molecular level. To show this unambiguously, a planar-aligned negative dielectric aniostropy achiral nematic liquid crystal was placed in contact with the surface and subjected to an electric field E. The nematic director was found to undergo an azimuthal rotation approximately linear in E. This so-called "surface electroclinic effect" is a signature of surface chirality and was not observed when the polyimide was treated for a centrosymmetric topography, and therefore was nonchiral. PMID:20867414

  1. Bootstrapping ${\\mathcal N}=2$ chiral correlators

    CERN Document Server

    Lemos, Madalena

    2016-01-01

    We apply the numerical bootstrap program to chiral operators in four-dimensional ${\\mathcal N}=2$ SCFTs. In the first part of this work we study four-point functions in which all fields have the same conformal dimension. We give special emphasis to bootstrapping a specific theory: the simplest Argyres-Douglas fixed point with no flavor symmetry. In the second part we generalize our setup and consider correlators of fields with unequal dimension. This is an example of a mixed correlator and allows us to probe new regions in the parameter space of ${\\mathcal N}=2$ SCFTs. In particular, our results put constraints on relations in the Coulomb branch chiral ring and on the curvature of the Zamolodchikov metric.

  2. Chiral fermions in asymptotically safe quantum gravity

    Science.gov (United States)

    Meibohm, J.; Pawlowski, J. M.

    2016-05-01

    We study the consistency of dynamical fermionic matter with the asymptotic safety scenario of quantum gravity using the functional renormalisation group. Since this scenario suggests strongly coupled quantum gravity in the UV, one expects gravity-induced fermion self-interactions at energies of the Planck scale. These could lead to chiral symmetry breaking at very high energies and thus to large fermion masses in the IR. The present analysis which is based on the previous works (Christiansen et al., Phys Rev D 92:121501, 2015; Meibohm et al., Phys Rev D 93:084035, 2016), concludes that gravity-induced chiral symmetry breaking at the Planck scale is avoided for a general class of NJL-type models. We find strong evidence that this feature is independent of the number of fermion fields. This finding suggests that the phase diagram for these models is topologically stable under the influence of gravitational interactions.

  3. Restoration of chiral symmetry: a supergravity perspective

    International Nuclear Information System (INIS)

    The supergravity dual of N regular and M fractional D3-branes on the conifold has a naked singularity in the infrared. Supersymmetric resolution of this singularity requires deforming the conifold: this is the supergravity dual of chiral symmetry breaking. Buchel suggested that at sufficiently high temperature there is no need to deform the conifold: the singularity may be cloaked by a horizon. This would be the supergravity manifestation of chiral symmetry restoration. In previous work [hep-th/0102105] the ansatz and the system of second-order radial differential equations necessary to find such a solution were written down. In this paper we find smooth solutions to this system in a perturbation theory that is valid when the Hawking temperature of the horizon is very high. (author)

  4. Applications of in-medium chiral dynamics

    International Nuclear Information System (INIS)

    A relativistic nuclear energy density functional is developed, guided by two important features that establish connections with chiral dynamics and the symmetry breaking pattern of low-energy QCD: a) strong scalar and vector fields related to in-medium changes of QCD vacuum condensates; b) long- and intermediate-range interactions generated by one-and two-pion exchange, derived from in-medium chiral perturbation theory, with explicit inclusion of Δ(1232) excitations. Applications are presented for the the description of ground-state properties and collective excitations of medium and heavy nuclei. The extension to hypernuclei are also presented, showing a new interpretation of the Λ-nucleus spin-orbit potential.

  5. Helical chirality induction of expanded porphyrin analogues

    Indian Academy of Sciences (India)

    Jun-Ichiro Setsune

    2012-11-01

    Expanded porphyrin analogues with unique figure-eight conformation were prepared by way of useful pyrrole intermediates such as bis(azafulvene)s and 2-borylpyrrole. Supramolecular chirogenesis of cyclooctapyrrole O1 with 32-cycloconjugation was successfully applied to determine absolute configuration of chiral carboxylic acids. Dinuclear CuII complex of cyclooctapyrrole O2 with interrupted -conjugation was resolved by HPLC into enantiomers and their helical handedness was determined by theoretical simulation of their CD spectral pattern. Enantioselective induction of helicity in the metal helicate formation in the presence of a chiral promoter was demonstrated by using ()-(+)-1-(1-phenyl)ethylamine that favoured , helicity. Dinuclear CoII complexes of cyclotetrapyrroletetrapyridine O3 were found to be substitution labile and pick up amino acid anions in water. Those amino acid complexes of O3Co2 were rendered to adopt a particular unidirectional helical conformation preferentially depending on the ligated amino acid anion.

  6. Magnetic rotation and chiral symmetry breaking

    Indian Academy of Sciences (India)

    Ashok Kumar Jain; Amita

    2001-08-01

    The deformed mean field of nuclei exhibits various geometrical and dynamical symmetries which manifest themselves as various types of rotational and decay patterns. Most of the symmetry operations considered so far have been defined for a situation wherein the angular momentum coincides with one of the principal axes and the principal axis cranking may be invoked. New possibilities arise with the observation of rotational features in weakly deformed nuclei and now interpreted as magnetic rotational bands. More than 120 MR bands have now been identified by filtering the existing data. We present a brief overview of these bands. The total angular momentum vector in such bands is tilted away from the principal axes. Such a situation gives rise to several new possibilities including breaking of chiral symmetry as discussed recently by Frauendorf. We present the outcome of such symmetries and their possible experimental verification. Some possible examples of chiral bands are presented.

  7. Practical chiral alcohol manufacture using ketoreductases.

    Science.gov (United States)

    Huisman, Gjalt W; Liang, Jack; Krebber, Anke

    2010-04-01

    Over the past two years the application of ketoreductases in the commercial synthesis of chiral alcohols has undergone a revolution. Biocatalysts are now often the preferred catalyst for the synthesis of chiral alcohols via ketone reduction and are displacing reagents and chemocatalysts that only recently were considered break-through process solutions themselves. Tailor-made enzymes can now be generated from advanced, non-natural variants using HTP screening and modern molecular biology techniques. At the same time, global economic and environmental pressures direct industrial process development toward versatile platforms that can be applied to the different stages of product development. We will discuss the technologies that have emerged over the past years that have guided biocatalysis from the bottom of the toolbox, to the power tool of choice. PMID:20071211

  8. Chiral discrimination in biomimetic systems: Phenylalanine

    Indian Academy of Sciences (India)

    K Thirumoorthy; K Soni; T Arun; N Nandi

    2007-09-01

    Chiral discrimination and recognition is important in peptide biosynthesis, amino acid synthesis and drug designing. Detailed structural information is available about the peptide synthesis in ribosome. However, no detailed study is available about the discrimination in peptide synthesis. We study the conformational energy variation of neutral methoxy phenyl alanine molecule as a function of its different dihedral angle to locate the minimum energy conformation using quantum chemical theory. We compared the intermolecular energy surfaces of phenyl alanine molecule in its neutral and zwitterionic state using quantum chemical theory as a function of distance and mutual orientation. The energy surfaces are studied with rigid geometry by varying the distance and orientation. The potential energy surfaces of - and - pairs are found to be dissimilar and reflect the underlying chirality of the homochiral pair and racemic nature of the heterochiral pair. The intermolecular energy surface of homochiral pair is more favourable than the corresponding energy surface of heterochiral pair.

  9. Imprintable membranes from incomplete chiral coalescence

    Science.gov (United States)

    Zakhary, Mark J.; Gibaud, Thomas; Nadir Kaplan, C.; Barry, Edward; Oldenbourg, Rudolf; Meyer, Robert B.; Dogic, Zvonimir

    2014-01-01

    Coalescence is an essential phenomenon that governs the equilibrium behaviour in a variety of systems from intercellular transport to planetary formation. In this report, we study coalescence pathways of circularly shaped two-dimensional colloidal membranes, which are one rod-length-thick liquid-like monolayers of aligned rods. The chirality of the constituent rods leads to three atypical coalescence pathways that are not found in other simple or complex fluids. In particular, we characterize two pathways that do not proceed to completion but instead produce partially joined membranes connected by line defects—π-wall defects or alternating arrays of twisted bridges and pores. We elucidate the structure and energetics of these defects and ascribe their stability to a geometrical frustration inherently present in chiral colloidal membranes. Furthermore, we induce the coalescence process with optical forces, leading to a robust on-demand method for imprinting networks of channels and pores into colloidal membranes.

  10. Optical tractor beam with chiral light

    Science.gov (United States)

    Fernandes, David E.; Silveirinha, Mário G.

    2015-06-01

    We suggest a novel mechanism to induce the motion of a chiral material body towards an optical source with no optical traps. Our solution is based on the interference between a chiral light beam and its reflection on an opaque mirror. Surprisingly, it is theoretically shown that the electromagnetic response of the material may be tailored in such a way that independent of the specific body location with respect to the mirror, it is always pulled upstream against the photon flow associated with the incoming wave. Moreover, it is proven that by controlling the handedness of the incoming light it may be possible to harness the sign of the optical force, switching from a pulling force to a pushing force.

  11. Optical Tractor Beam with Chiral Light

    CERN Document Server

    Fernandes, David E

    2015-01-01

    We suggest a novel mechanism to induce the motion of a chiral material body towards an optical source. Our solution is based on the interference between a chiral light beam and its reflection on an opaque mirror. Surprisingly, it is theoretically shown that the electromagnetic response of the material may be tailored in such a way that independent of the specific body location with the respect to the mirror, it is always pushed upstream against the photon flow associated with the incoming wave. Moreover, it is proven that by controlling the handedness of the incoming light it may be possible to harness the sign of the optical force, switching from a pulling force to a pushing force.

  12. A primer for Chiral Perturbative Theory

    International Nuclear Information System (INIS)

    Chiral Perturbation Theory, as effective field theory, is a commonly accepted and well established working tool, approximating quantum chromodynamics at energies well below typical hadron masses. This volume, based on a number of lectures and supplemented with additional material, provides a pedagogical introduction for graduate students and newcomers entering the field from related areas of nuclear and particle physics. Starting with the the Lagrangian of the strong interactions and general symmetry principles, the basic concepts of Chiral Perturbation Theory in the mesonic and baryonic sectors are developed. The application of these concepts is then illustrated with a number of examples. A large number of exercises (81, with complete solutions) are included to familiarize the reader with helpful calculational techniques. (orig.)

  13. Chiral Magnetic Effect Task Force Report

    CERN Document Server

    Skokov, Vladimir; Koch, Volker; Schlichting, Soeren; Thomas, Jim; Voloshin, Sergei; Wang, Gang; Yee, Ho-Ung

    2016-01-01

    In this report, we briefly examine the current status of the study of the chiral magnetic effect including theory and experimental progress. We recommend future strategies for resolving uncertainties in interpretation including recommendations for theoretical work, recommendations for measurements based on data collected in the past five years, and recommendations for beam use in the coming years of RHIC. We have specifically investigated the case for colliding nuclear isobars (nuclei with the same mass but different charge) and find the case compelling. We recommend that a program of nuclear isobar collisions to isolate the chiral magnetic effect from background sources be placed as a high priority item in the strategy for completing the RHIC mission.

  14. A Nonperturbative Regulator for Chiral Gauge Theories

    CERN Document Server

    Grabowska, Dorota M

    2015-01-01

    We propose a nonperturbative gauge invariant regulator for $d$-dimensional chiral gauge theories on the lattice. The method involves simulating domain wall fermions in $d+1$ dimensions with quantum gauge fields that reside on one $d$-dimensional surface and are extended into the bulk via gradient flow. The result is a theory of gauged fermions plus mirror fermions, where the mirror fermions couple to the gauge fields via a form factor that becomes exponentially soft with the separation between domain walls. The resultant theory has a local $d$-dimensional interpretation if and only if the chiral fermion representation is anomaly free. A physical realization of this construction leads to mirror fermions in the Standard Model with soft form factors for gauge fields and gravity. These mirror particles could evade detection except by sensitive probes at extremely low energy, and yet still affect vacuum topology, and could gravitate differently than conventional matter.

  15. Nonperturbative Regulator for Chiral Gauge Theories?

    Science.gov (United States)

    Grabowska, Dorota M.; Kaplan, David B.

    2016-05-01

    We propose a nonperturbative gauge-invariant regulator for d -dimensional chiral gauge theories on the lattice. The method involves simulating domain wall fermions in d +1 dimensions with quantum gauge fields that reside on one d -dimensional surface and are extended into the bulk via gradient flow. The result is a theory of gauged fermions plus mirror fermions, where the mirror fermions couple to the gauge fields via a form factor that becomes exponentially soft with the separation between domain walls. The resultant theory has a local d -dimensional interpretation only if the chiral fermion representation is anomaly free. A physical realization of this construction would imply the existence of mirror fermions in the standard model that are invisible except for interactions induced by vacuum topology, and which could gravitate differently than conventional matter.

  16. A primer for Chiral Perturbative Theory

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, Stefan [Mainz Univ. (Germany). Inst. fuer Kernphysik; Schindler, Matthias R. [South Carolina Univ., Columbia, SC (United States). Dept. of Physics; George Washington Univ., Washington, DC (United States). Dept. of Physics

    2012-07-01

    Chiral Perturbation Theory, as effective field theory, is a commonly accepted and well established working tool, approximating quantum chromodynamics at energies well below typical hadron masses. This volume, based on a number of lectures and supplemented with additional material, provides a pedagogical introduction for graduate students and newcomers entering the field from related areas of nuclear and particle physics. Starting with the the Lagrangian of the strong interactions and general symmetry principles, the basic concepts of Chiral Perturbation Theory in the mesonic and baryonic sectors are developed. The application of these concepts is then illustrated with a number of examples. A large number of exercises (81, with complete solutions) are included to familiarize the reader with helpful calculational techniques. (orig.)

  17. A primer for chiral perturbation theory

    CERN Document Server

    Scherer, Stefan

    2012-01-01

    Chiral Perturbation Theory, as effective field theory, is a commonly accepted and well established working tool, approximating quantum chromodynamics at energies well below typical hadron masses. This volume, based on a number of lectures and supplemented with additional material, provides a pedagogical introduction for graduate students and newcomers entering the field from related areas of nuclear and particle physics. Starting with the the Lagrangian of the strong interactions and general symmetry principles, the basic concepts of Chiral Perturbation Theory in the mesonic and baryonic sectors are developed. The application of these concepts is then illustrated with a number of examples. A large number of exercises (81, with complete solutions) are included to familiarize the reader with helpful calculational techniques.

  18. Testing Chiral Symmetry Breaking at DAPHNE

    OpenAIRE

    M. R. Pennington

    1996-01-01

    The spontaneous breakdown of the chiral symmetry of the QCD Lagrangian ensures that $\\pi\\pi$ interactions are weak at low energies. How weak depends on the nature of explicit symmetry breaking. Measurements of $K_{e4}$ decays at DA$\\Phi$NE will provide a unique insight into this mechanism and test whether the $q{\\overline q}$--condensate is large or small.

  19. From Ostwald Ripening to Single Chirality

    OpenAIRE

    Noorduin, Wim L.; Vlieg, Elias; Kellogg, Richard M.; Kaptein, Bernard

    2009-01-01

    A century ago Wilhelm Ostwald received the Nobel Prize for Chemistry. Although Ostwald was never significantly involved with the phenomenon of chirality, one of his discoveries, Ostwald ripening, is thought to be involved in a recently discovered method in which grinding-induced attrition is used to transform racemic conglomerates virtually quantitatively into a single enantiomer. In this Minireview the basic concepts developed by Ostwald will be introduced, followed by a summary of the curre...

  20. Chiral Negative-Index Metamaterials in Terahertz

    OpenAIRE

    Zhang, Shuang; Park, Yong-Shik; Li, Jensen; Lu, Xinchao; Zhang, Weili; Zhang, Xiang

    2008-01-01

    Negative index metamaterials (NIMs) give rise to unusual and intriguing properties and phenomena, which may lead to important applications such as superlens, subwavelength cavity and slow light devices. However, the negative refractive index in metamaterials normally requires a stringent condition of simultaneously negative permittivity and negative permeability. A new class of negative index metamaterials - chiral NIMs, have been recently proposed. In contrast to the conventional NIMs, chira...

  1. Chiral fermions in asymptotically safe quantum gravity

    OpenAIRE

    Meibohm, Jan; Pawlowski, Jan M.

    2016-01-01

    We study the consistency of dynamical fermionic matter with the asymptotic safety scenario of quantum gravity using the functional renormalisation group. Since this scenario suggests strongly coupled quantum gravity in the UV, one expects gravity-induced fermion self-interactions at energies of the Planck-scale. These could lead to chiral symmetry breaking at very high energies and thus to large fermion masses in the IR. The present analysis which is based on the previous works \\cite{Christia...

  2. Lifetime measurements in chiral nucleus 130Cs

    Institute of Scientific and Technical Information of China (English)

    WANG Lie-Lin; WU Xiao-Guang; ZHU Li-Hua; LI Guang-Sheng; HAO Xin; ZHENG Yun; HE Chuang-Ye; WANG Lei; LI Xue-Qin; LIU Ying; PAN Bo; LI Zhong-Yu; DING Huai-Bo

    2009-01-01

    The level lifetimes in partner bands of 130Cs have been measured using the Doppler Shift Attenuation method. The high-spin states of 130Cs were populated via fusion evaporation reaction 124Sn(11B,5n)130Cs at a beam energy of 65 MeV. The absolute M1 and E2 transition probabilities have been deduced. The results indicate that the partner bands of 130Cs manifest the chiral properties.

  3. Test of Chirality in Nucleus 130Cs

    Institute of Scientific and Technical Information of China (English)

    吴晓光; 王烈林; 竺礼华; 李广生; 郝昕; 郑云; 贺创业; 李雪琴; 潘波; 刘颖; 汪雷; 赵延新; 李忠宇; 丁怀博

    2012-01-01

    The level lifetimes in partner bands of 130Cs have been measured using the Doppler Shift Attenuation method (DSAM). The high-spin states of 130Cs were populated via fusion evap- oration reaction 124Sn(11B; 5n)130Cs at a beam energy of 65 MeV. The absolute M1 and E2 transition probabilities have been deduced. The results indicate that the partner bands of 130Cs indeed manifest chiral properties.

  4. Electron quantum optics in ballistic chiral conductors

    OpenAIRE

    Bocquillon, E.; Freulon, V.; Parmentier, F. D.; Berroir, J.-M.; Plaçais, B.; Wahl, C.; Rech, J.; Jonckheere, T.; Martin, T; Grenier, C.; Ferraro, D.; Degiovanni, P.; Fève, G.

    2014-01-01

    The edge channels of the quantum Hall effect provide one dimensional chiral and ballistic wires along which electrons can be guided in optics like setup. Electronic propagation can then be analyzed using concepts and tools derived from optics. After a brief review of electron optics experiments performed using stationary current sources which continuously emit electrons in the conductor, this paper focuses on triggered sources, which can generate on-demand a single particle state. It first ou...

  5. Phenomenology of chiral damping in noncentrosymmetric magnets

    OpenAIRE

    Akosa, C. A.; Miron, I. M.; Gaudin, G.; Manchon, A.

    2015-01-01

    A phenomenology of magnetic chiral damping is proposed in the context of magnetic materials lacking inversion symmetry breaking. We show that the magnetic damping tensor adopts a general form that accounts for a component linear in magnetization gradient in the form of Lifshitz invariants. We propose different microscopic mechanisms that can produce such a damping in ferromagnetic metals, among which spin pumping in the presence of anomalous Hall effect and an effective "$s$-$d$" Dzyaloshinsk...

  6. Chiral unitary theory: Application to nuclear problems

    Indian Academy of Sciences (India)

    E Oset; D Cabrera; H C Chiang; C Garcia Recio; S Hirenzaki; S S Kamalov; J Nieves; Y Okumura; A Ramos; H Toki; M J Vicente Vacas

    2001-08-01

    In this talk we briefly describe some basic elements of chiral perturbation theory, , and how the implementation of unitarity and other novel elements lead to a better expansion of the -matrix for meson–meson and meson–baryon interactions. Applications are then done to the interaction in nuclear matter in the scalar and vector channels, antikaons in nuclei and - atoms, and how the meson properties are changed in a nuclear medium.

  7. Chirality and Cosmic Origin of Life

    OpenAIRE

    Sidharth, Burra G.

    2009-01-01

    Chirality or the property that distinguishes lefthandedness from righthandedness is an important aspect of the universe, starting from neutrinos, which are lefthanded. Fifteen years ago the author had proposed that life on the earth was formed through a dual process -- several key ingredients being transported from outer space to the earth by comets or meteorites and these in turn interacting with compounds already cooked up in the earth's seas. Several recent observations point to the fact t...

  8. Chiral Lagrangians and quark condensate in nuclei

    International Nuclear Information System (INIS)

    The evolution of density of quark condensate in nuclear medium with interacting nucleons, including the short range correlations is examined. Two chiral models are used, the linear sigma model and the non-linear one. It is shown that the quark condensate, as other observables, is independent on the variant selected. The application to physical pions excludes the linear sigma model as a credible one. The non-linear models restricted to pure s-wave pion-nucleon scattering are examined. (author)

  9. Structure Functions from Chiral Soliton Models

    OpenAIRE

    Weigel, H.(Physics Department, Stellenbosch University, Matieland 7602, South Africa); Gamberg, L.(Department of Physics, Penn State University-Berks, Reading, PA, 19610, U.S.A.); Reinhardt, H.

    1997-01-01

    We study nucleon structure functions within the bosonized Nambu-Jona-Lasinio (NJL) model where the nucleon emerges as a chiral soliton. We discuss the model predictions on the Gottfried sum rule for electron-nucleon scattering. A comparison with a low-scale parametrization shows that the model reproduces the gross features of the empirical structure functions. We also compute the leading twist contributions of the polarized structure functions $g_{1}(x)$ and $g_{2}(x)$ in this model. We compa...

  10. Nuclear electromagnetic currents from chiral EFT

    International Nuclear Information System (INIS)

    Using the method of unitary transformation in combination with chiral effective field theory we derive the pion exchange contributions to the two-nucleon electromagnetic current. A formal definition of the current operator in this scheme and the power counting is presented. We discuss the implications of additional unitary transformations that have to be present to ensure the renormalizability of the one-pion exchange current. Further, we give explicit and compact results for the current in coordinate-space.

  11. Circular Intensity Differential Scattering of chiral molecules

    Energy Technology Data Exchange (ETDEWEB)

    Bustamante, C.J.

    1980-12-01

    In this thesis a theory of the Circular Intensity Differential Scattering (CIDS) of chiral molecules as modelled by a helix oriented with respect to the direction of incidence of light is presented. It is shown that a necessary condition for the existence of CIDS is the presence of an asymmetric polarizability in the scatterer. The polarizability of the scatterer is assumed generally complex, so that both refractive and absorptive phenomena are taken into account.

  12. Chiral Biomarkers and Microfossils in Carbonaceous Meteorites

    Science.gov (United States)

    Hoover, Richard B.

    2010-01-01

    Homochirality of the biomolecules (D-sugars of DNA and RNA and L-amino acids of proteins) is a fundamental property of all life on Earth. Abiotic mechanisms yield racemic mixtures (D/L=1) of chiral molecules and after the death of an organism, the enantiopure chiral biomolecules slowly racemize. Several independent investigators have now established that the amino acids present in CI1 and CM2 carbonaceous meteorites have a moderate to strong excess of the L-enantiomer. Stable isotope data have established that these amino acids are both indigenous and extraterrestrial. Carbonaceous meteorites also contain many other strong chemical biomarkers including purines and pyrimidines (nitrogen heterocycles of nucleic acids); pristine and phytane (components of the chlorophyll pigment) and morphological biomarkers (microfossils of filamentous cyanobacteria). Energy dispersive X-ray Spectroscopy (EDS) analysis reveals that nitrogen is below the detectability level in most of the meteorite filaments as well as in Cambrian Trilobites and filaments of 2.7 Gya Archaean cyanobacteria from Karelia. The deficiency of nitrogen in the filaments and the total absence of sugars, of twelve of the life-critical protein amino acids, and two of the nucleobases of DNA and RNA provide clear and convincing evidence that these filaments are not modern biological contaminants. This paper reviews the chiral, chemical biomarkers morphological biomarkers and microfossils in carbonaceous meteorites. This paper reviews chiral and morphological biomarkers and discusses the missing nitrogen, sugars, protein amino acids, and nucleobases as ?bio-discriminators? that exclude modern biological contaminants as a possible explanation for the permineralized cyanobacterial filaments found in the meteorites.

  13. Synthesis of Resins with Chiral Salen Complexes

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ The enormous growth in the use of polymer resin supports in solid phase combinatorial synthesis, and related methodologies, has re-stimulated interest in the area of polymer-supported transition metal complex catalyst .The recently developed chiral salen-based for the enantioselective ring opening of meso epoxides and kinetic resolution of terminal epoxides are appealing candidates for immobilization on solid support. The catalysts are reading prepare from inexpensive components, and are amenable to modification for attachment to a solid support.

  14. Random Lattice QCD and chiral effective theories

    OpenAIRE

    Pavlovsky, O. V.

    2004-01-01

    Resent developments in the Random Matrix and Random Lattice Theories give a possibility to find low-energy theorems for many physical models in the Born-Infeld form. In our approach that based on the Random Lattice regularization of QCD we try to used the similar ideas in the low-energy baryon physics for finding of the low-energy theory for the chiral fields in the strong-coupling regime.

  15. Chiral perturbation theory for nucleon generalized parton distributions

    Energy Technology Data Exchange (ETDEWEB)

    Diehl, M. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Manashov, A. [Regensburg Univ. (Germany). Inst. fuer Physik 1 - Theoretische Physik]|[Sankt-Petersburg State Univ. (Russian Federation). Dept. of Theoretical Physics; Schaefer, A. [Regensburg Univ. (Germany). Inst. fuer Physik 1 - Theoretische Physik

    2006-08-15

    We analyze the moments of the isosinglet generalized parton distributions H, E, H, E of the nucleon in one-loop order of heavy-baryon chiral perturbation theory. We discuss in detail the construction of the operators in the effective theory that are required to obtain all corrections to a given order in the chiral power counting. The results will serve to improve the extrapolation of lattice results to the chiral limit. (orig.)

  16. Fermion self-energy in magnetized chirally asymmetric QED matter

    CERN Document Server

    Rybalka, D O

    2016-01-01

    The fermion self-energy is calculated for a cold QED plasma with chiral chemical potential in a magnetic field. It is found that a momentum shift parameter dynamically generated in such a plasma leads to a modification of the chiral magnetic effect current. It is argued that the momentum shift parameter can be relevant for the evolution of magnetic field in the chirally asymmetric primordial plasma in the early Universe.

  17. Chiral Topological Superconductor From the Quantum Hall State

    OpenAIRE

    Qi, Xiao-Liang; Hughes, Taylor L.; Zhang, Shou-Cheng

    2010-01-01

    The chiral topological superconductor in two dimensions has a full pairing gap in the bulk and a single chiral Majorana state at the edge. The vortex of the chiral superconducting state carries a Majorana zero mode which is responsible for the non-abelian statistics of the vortices. Despite intensive searches, this novel superconducting state has not yet been identified in nature. In this paper, we consider a quantum Hall or a quantum anomalous Hall state near the plateau transition, and in p...

  18. Acoustic orbital angular momentum transfer to matter by chiral scattering

    OpenAIRE

    Wunenburger, Régis; Israel, Juan; Lozano, Vazquez; Brasselet, Etienne

    2015-01-01

    We report on orbital angular momentum exchange between sound and matter mediated by a non-dissipative chiral scattering process. An experimental demonstration is made possible by irradiating a three-dimensional printed, spiral-shaped chiral object with an incident ultrasonic beam carrying zero orbital angular momentum. Chiral refraction is shown to impart a nonzero orbital angular momentum to the scattered field and to rotate the object. This result constitutes a proof of concept of a novel k...

  19. The anomalous Hall conductivity due to the vector spin chirality

    OpenAIRE

    Taguchi, Katsuhisa; Tatara, Gen

    2008-01-01

    We study theoretically the anomalous Hall effect due to the vector spin chirality carried by the local spins in the $s$-$d$ model. We will show that the vector spin chirality indeed induces local Hall effect in the presence of the electron spin polarization, while the global Hall effect vanishes if electron transport is homogeneous. This anomalous Hall effect can be interpreted in terms of the rotational component of the spin current associated with the vector chirality.

  20. Chiral Ground States in a Frustrated Holographic Superconductor

    CERN Document Server

    Nishida, Mitsuhiro

    2015-01-01

    Frustration is an important phenomenon in condensed matter physics because it can introduce a new order parameter such as chirality. Towards understanding a mechanism of the frustration in strongly correlated systems, we study a holographic superconductor model with three scalar fields and an interband Josephson coupling, which is important for the frustration. We analyze free energy of solutions of the model to determine ground states. We find chiral ground states, which have nonzero chirality.

  1. Magnetotransport phenomena related to the chiral anomaly in Weyl semimetals

    Science.gov (United States)

    Spivak, B. Z.; Andreev, A. V.

    2016-02-01

    We present a theory of magnetotransport phenomena related to the chiral anomaly in Weyl semimetals. We show that conductivity, thermal conductivity, thermoelectric, and the sound absorption coefficients exhibit strong and anisotropic magnetic field dependencies. We also discuss properties of magnetoplasmons and magnetopolaritons, whose existences are entirely determined by the chiral anomaly. Finally, we discuss the conditions of applicability of the quasiclassical description of electron transport phenomena related to the chiral anomaly.

  2. Relativistic Chiral Theory of Nuclear Matter and QCD Constraints

    OpenAIRE

    Chanfray, G.; Ericson, M.

    2009-01-01

    Talk given by G. Chanfray at PANIC 08, Eilat (Israel), november 10-14, 2008 We present a relativistic chiral theory of nuclear matter which includes the effect of confinement. Nuclear binding is obtained with a chiral invariant scalar background field associated with the radial fluctuations of the chiral condensate Nuclear matter stability is ensured once the scalar response of the nucleon depending on the quark confinement mechanism is properly incorporated. All the parameters are fixed o...

  3. Low-Energy Constants from Resonance Chiral Theory

    OpenAIRE

    Pich, Antonio

    2008-01-01

    I discuss the recent attempts to build an effective chiral Lagrangian incorporating massive resonance states. A useful approximation scheme to organize the resonance Lagrangian is provided by the large-Nc limit of QCD. Integrating out the resonance fields, one recovers the usual chiral perturbation theory Lagrangian with explicit values for the low-energy constants, parameterized in terms of resonance masses and couplings. The resonance chiral theory generates Green functions that interpolate...

  4. A molecular propeller effect for chiral separation and analysis

    OpenAIRE

    Clemens, Jonathon B.; Kibar, Osman; Chachisvilis, Mirianas

    2015-01-01

    Enantiomers share nearly identical physical properties but have different chiral geometries, making their identification and separation difficult. Here we show that when exposed to a rotating electric field, the left- and right-handed chiral molecules rotate with the field and act as microscopic propellers; moreover, owing to their opposite handedness, they propel along the axis of field rotation in opposite directions. We introduce a new molecular parameter called hydrodynamic chirality to c...

  5. Derivation of Chiral Lagrangians from Random Lattice QCD

    CERN Document Server

    Pavlovsky, O V

    2004-01-01

    In our work we extend the ideas of the derivation of the chiral effective theory from the lattice QCD [1] to the case of the random lattice regularization of QCD. Such procedure allows in principle to find contribution of any order into the chiral effective lagrangian. It is shown that an infinite subseries of the chiral perturbation can be summed up into tne Born-Infeld term and the logarithmic correction to them.

  6. Langevin evolution of disoriented chiral condensate

    International Nuclear Information System (INIS)

    As the matter produced in a relativistic heavy ion collision cools through the QCD phase transition, the dynamical evolution of the chiral condensate will be driven out of thermal equilibrium. As a prelude to analyzing this evolution, and in particular as a prelude to learning how rapid the cooling must be in order for significant deviations from equilibrium to develop, we present a detailed analysis of the time-evolution of an idealized region of disoriented chiral condensate. We set up a Langevin field equation which can describe the evolution of these (or more realistic) linear sigma model configurations in contact with a heat bath representing the presence of other shorter wavelength degrees of freedom. We first analyze the model in equilibrium, paying particular attention to subtracting ultraviolet divergent classical terms and replacing them by their finite quantum counterparts. We use known results from lattice gauge theory and chiral perturbation theory to fix nonuniversal constants. The result is a theory which is ultraviolet cutoff independent and that reproduces quantitatively the expected equilibrium behavior of the quantum field theory of pions and σ fields over a wide range of temperatures. Finally, we estimate the viscosity η(T), which controls the dynamical timescale in the Langevin equation, by requiring that the timescale for DCC decay agrees with previous calculations. The resulting η(T) is larger than that found perturbatively. We also determine the temperature below which the classical field Langevin equation ceases to be a good model for the quantum field dynamics

  7. Dynamics and Stability of Chiral Fluid

    CERN Document Server

    Mishustin, Igor N; Denicol, Gabriel S; Torrieri, Giorgio

    2014-01-01

    Starting from the linear sigma model with constituent quarks we derive the chiral fluid dynamics where hydrodynamic equations for the quark fluid are coupled to the equation of motion for the order-parameter field. In a static system at thermal equilibrium this model leads to a chiral phase transition which, depending on the choice of the quark-meson coupling constant, could be a crossover or a first order one. We investigate the stability of the chiral fluid in the static and expanding backgrounds by considering the evolution of perturbations with respect to the mean-field solution. In the static background the spectrum of plane-wave perturbations consists of two branches, one corresponding to the sound waves and another to the sigma-meson excitations. For large couplings these two branches "cross" and the excitation spectrum acquires exponentially growing modes. The stability analysis is also done for the Bjorken-like background solution by explicitly solving the time-dependent differential equation for per...

  8. Concise theory of chiral lipid membranes

    CERN Document Server

    Tu, Z C

    2007-01-01

    A theory of chiral lipid membranes is proposed on the basis of a concise free energy density which includes the contributions of the bending and the surface tension of membranes, as well as the chirality and orientational variation of tilting molecules. This theory is consistent with the previous experiments [J.M. Schnur \\textit{et al.}, Science \\textbf{264}, 945 (1994); M.S. Spector \\textit{et al.}, Langmuir \\textbf{14}, 3493 (1998); Y. Zhao, \\textit{et al.}, Proc. Natl. Acad. Sci. USA \\textbf{102}, 7438 (2005)] on self-assembled chiral lipid membranes of DC$_{8,9}$PC. A torus with the ratio between its two generated radii larger than $\\sqrt{2}$ is predicted from the Euler-Lagrange equations. It is found that tubules with helically modulated tilting state are not admitted by the Euler-Lagrange equations, and that they are less energetically favorable than helical ripples in tubules. The pitch angles of helical ripples are theoretically estimated to be about 0$^\\circ$ and 35$^\\circ$, which are close to the mo...

  9. Chiral analysis of baryon form factors

    International Nuclear Information System (INIS)

    This work presents an extensive theoretical investigation of the structure of the nucleon within the standard model of elementary particle physics. In particular, the long range contributions to a number of various form factors parametrizing the interactions of the nucleon with an electromagnetic probe are calculated. The theoretical framework for those calculations is chiral perturbation theory, the exact low energy limit of Quantum Chromo Dynamics, which describes such long range contributions in terms of a pion-cloud. In this theory, a nonrelativistic leading one loop order calculation of the form factors parametrizing the vector transition of a nucleon to its lowest lying resonance, the Δ, a covariant calculation of the isovector and isoscalar vector form factors of the nucleon at next to leading one loop order and a covariant calculation of the isoscalar and isovector generalized vector form factors of the nucleon at leading one loop order are performed. In order to perform consistent loop calculations in the covariant formulation of chiral perturbation theory an appropriate renormalization scheme is defined in this work. All theoretical predictions are compared to phenomenology and results from lattice QCD simulations. These comparisons allow for a determination of the low energy constants of the theory. Furthermore, the possibility of chiral extrapolation, i.e. the extrapolation of lattice data from simulations at large pion masses down to the small physical pion mass is studied in detail. Statistical as well as systematic uncertainties are estimated for all results throughout this work. (orig.)

  10. Chiral Receiving Antenna With Low Backscattering Levels

    CERN Document Server

    Karilainen, Antti O

    2011-01-01

    Receiving antennas absorb power from incident waves, but they also re-radiate some power into surrounding space. If a receiving antenna is to be used as a sensor which should not disturb the object under study, it should scatter as little power as possible in the receiving direction. We propose to use a chiral element composed of two orthogonal chiral particles as a low-scattering sensor.The element can transmit and receive circular polarization in all directions with the Huygens' pattern. We derive the vector effective length for the antenna using the small dipole approximation for the chiral particles. We observe that the element does not backscatter, regardless of the polarization, when the incidence direction is normal to the plane of the particles. Scattered fields, scattered axial ratio, and the scattering cross section are presented. We show that the zero-backscattering property holds also for the antenna element when it is capable to receive all the available power with conjugate loading. The approxim...

  11. Chiral symmetry breaking in QCD Lite

    CERN Document Server

    Engel, Georg P; Lottini, Stefano; Sommer, Rainer

    2014-01-01

    A distinctive feature of the presence of spontaneous chiral symmetry breaking in QCD is the condensation of low modes of the Dirac operator near the origin. The rate of condensation must be equal to the slope of (Mpi^2 Fpi^2)/2 with respect to the quark mass m in the chiral limit, where Mpi and Fpi are the mass and the decay constant of the Nambu-Goldstone bosons. We compute the spectral density of the (Hermitian) Dirac operator, the quark mass, the pseudoscalar meson mass and decay constant by numerical simulations of lattice QCD with two light degenerate Wilson quarks. We use CLS lattices at three values of the lattice spacing in the range 0.05-0.08 fm, and for several quark masses corresponding to pseudoscalar mesons masses down to 190 MeV. Thanks to this coverage of parameters space, we can extrapolate all quantities to the chiral and continuum limits with confidence. The results show that the low quark modes do condense in the continuum as expected by the Banks-Casher mechanism, and the rate of condensat...

  12. Energetic molding of chiral magnetic bubbles

    Science.gov (United States)

    Lau, Derek; Sundar, Vignesh; Zhu, Jian-Gang; Sokalski, Vincent

    2016-08-01

    Topologically protected magnetic structures such as skyrmions and domain walls (DWs) have drawn a great deal of attention recently due to their thermal stability and potential for manipulation by spin current, which is the result of chiral magnetic configurations induced by the interfacial Dzyaloshinskii-Moriya interaction (DMI). Designing devices that incorporate DMI necessitates a thorough understanding of how the interaction presents and can be measured. One approach is to measure growth asymmetry of chiral bubble domains in perpendicularly magnetized thin films, which has been described elsewhere by thermally activated DW motion. Here, we demonstrate that the anisotropic angular dependence of DW energy originating from the DMI is critical to understanding this behavior. Domains in Co/Ni multilayers are observed to preferentially grow into nonelliptical teardrop shapes, which vary with the magnitude of an applied in-plane field. We model the domain profile using energetic calculations of equilibrium shape via the Wulff construction, which serves as a new paradigm for describing chiral domains that explains both the teardrop shape and the reversal of growth symmetry at large fields.

  13. N phi state in chiral quark model

    CERN Document Server

    Huang, F; Zhang, Z Y

    2006-01-01

    The structures of N phi states with spin-parity J^{p}=3/2^- and J^p=1/2^- are dynamically studied in both the chiral SU(3) quark model and the extended chiral SU(3) quark model by solving a resonating group method (RGM) equation. The model parameters are taken from our previous work, which gave a satisfactory description of the energies of the baryon ground states, the binding energy of the deuteron, the nucleon-nucleon (NN) scattering phase shifts, and the hyperon-nucleon (YN) cross sections. The channel coupling of N phi and Lambda K* is considered, and the effect of the tensor force which results in the mixing of S and D waves is also investigated. The results show that the N phi state has an attractive interaction, and in the extended chiral SU(3) quark model such an attraction plus the channel coupling effect can consequently make for an N phi quasi-bound state with several MeV binding energy.

  14. Evidence for chirality in 105Rh

    International Nuclear Information System (INIS)

    Complete text of publication follows. High-spin states in 105Rh were populated by the 96Zr(13C,p3n) reaction at beam energies of 51 and 58 MeV, and studied using the EUROBALL IV γ-ray spectrometer and the DIAMANT charged particle array. A pair of nearly degenerate ΔI = 1 three-quasiparticle bands (bands 4 and 5 in Fig. 1) with the same spins and parity have been observed. Comparison of the experimental results with tilted axis cranking calculations (see Fig. 2) confirms the chiral character of the two bands, while arguments based on the excitation of particles within the πg9/2ν(h11/2)2 configuration of the yrast band and comparison with the previously observed γ band (band 2) exclude the other possible interpretations. This is the first experimental evidence for three-quasiparticle chiral structure in the A∼100 region, and the first simultaneous observation of a γ band and chiral partner bands in one nucleus. The results are published in Ref. 1. (author)

  15. Enantiomeric separations of chiral pharmaceuticals using chirally modified tetrahexahedral Au nanoparticles

    Science.gov (United States)

    Shukla, N.; Yang, D.; Gellman, A. J.

    2016-06-01

    Tetrahexahedral (THH, 24-sided) Au nanoparticles modified with D- or L-cysteine (Cys) have been used as enantioselective separators of the chiral pharmaceutical propranolol (PLL) in solution phase. Polarimetry has been used to measure the rotation of linearly polarized light by solutions containing mixtures of PLL and Cys/THH-Au NPs with varying enantiomeric excesses of each. Polarimetry yields clear evidence of enantiospecific adsorption of PLL onto the Cys/THH-Au NPs. This extends prior work using propylene oxide as a test chiral probe, by using the crystalline THH Au NPs with well-defined facets to separate a real pharmaceutical. This work suggests that chiral nanoparticles, coupled with a density separation method such as centrifugation, could be used for enantiomeric purification of real pharmaceuticals. A simple robust model developed earlier has also been used to extract the enantiospecific equilibrium constants for R- and S-PLL adsorption onto the D- and L-Cys/THH-Au NPs.

  16. Rationalization of chirality induction and inversion in a zinc trisporphyrinate by a chiral monoalcohol.

    Science.gov (United States)

    Li, Li; Hu, Chuanjiang; Shi, Bo; Wang, Yong

    2016-05-10

    A new host-guest system is formed between a benzene tricarboxamide linked zinc trisporphyrinate and a chiral monoalcohol (1-phenylethylalcohol). CD spectra show the chirality induction and inversion processes, which are controlled by the corresponding 1 : 1 and 1 : 2 coordination complexes. The binding constants calculated by UV-vis and CD spectral data are much larger than that for [Zn(TPP)] (TPP = tetraphenylporphyrin). The crystallographic structure of the host-guest complex reveals that multiple intramolecular hydrogen bonds and π-π interactions could contribute to its high binding affinity to 1-phenylethylalcohol. The DFT calculations suggest that the spatial orientations of porphyrin moieties change from the 1 : 1 complex to the 1 : 2 complex. The chirality induction and inversion processes are rationalized by the summation of pairwise interactions among multichromophores according to pairwise additivity. PMID:27074900

  17. Chiral symmetry breaking and vacuum polarization in a bag

    CERN Document Server

    Yasui, S

    2006-01-01

    We study the effects of a finite quark mass in the hedgehog configuration in the two phase chiral bag model. We discuss the chiral properties, such as the fractional baryon number and the chiral Casimir energy, by using the Debye expansion for the analytical calculation and the Strutinsky's smearing method for the numerical computation. It is shown that the fractional baryon number carried by massive quarks in the vacuum is canceled by that in the meson sector. A finite term of the chiral Casimir energy is obtained with subtraction of the logarithmic divergence term.

  18. Chirally enhanced solubilization through perylene-based surfactant

    International Nuclear Information System (INIS)

    Recently we introduced a rationally designed surfactant which forms energy transfer complexes with carbon nanotubes. We investigate the chiral selectivity of this compound, a perylene derived surfactant, through photoluminescence (PL) measurements, and find a strong enhancement of the luminescence intensity for one particular group of chiralities. The effect is striking, with luminescence increases of several hundred percent. Chiral selectivity of the investigated surfactant compound as compared to solubilization through sodium cholate (SC). Small numbers indicate chirality, large numbers laola family. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Chirally enhanced solubilization through perylene-based surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Friederike; Reich, Stephanie; Setaro, Antonio [Department of Physics, Freie Universitaet Berlin, Arnimallee 14, 14195 Berlin (Germany); Heek, Timm; Haag, Rainer [Department of Chemistry, Freie Universitaet Berlin, Takustrasse 3, 14195 Berlin (Germany)

    2012-12-15

    Recently we introduced a rationally designed surfactant which forms energy transfer complexes with carbon nanotubes. We investigate the chiral selectivity of this compound, a perylene derived surfactant, through photoluminescence (PL) measurements, and find a strong enhancement of the luminescence intensity for one particular group of chiralities. The effect is striking, with luminescence increases of several hundred percent. Chiral selectivity of the investigated surfactant compound as compared to solubilization through sodium cholate (SC). Small numbers indicate chirality, large numbers laola family. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. OSp(1,4)-superfields in chiral representation

    International Nuclear Information System (INIS)

    The properties of OSp(1.4)-superfields in splitting (chiral)parametrization of the superspace of OSp(1.4)/O(1.3) are studied. The connection is found between the real and chiral bases in superspace and construct covariant derivatives and invariant integration measures in chiral bases. The group structure of chiral representations of OSp(1.4) is studied in detail. The simplest linear OSp(1.4)-invariant models are presented: the OSp(1.4)-analog of the Wess-Zumino model and OSp(1.4)-extension of the Yang-Mills theory. The relation of the described formalism to supergravity is also discussed

  1. Topological state engineering by potential impurities on chiral superconductors

    Science.gov (United States)

    Kaladzhyan, Vardan; Röntynen, Joel; Simon, Pascal; Ojanen, Teemu

    2016-08-01

    In this work we consider the influence of potential impurities deposited on top of two-dimensional chiral superconductors. As discovered recently, magnetic impurity lattices on an s -wave superconductor may give rise to a rich topological phase diagram. We show that a similar mechanism takes place in chiral superconductors decorated by nonmagnetic impurities, thus avoiding the delicate issue of magnetic ordering of adatoms. We illustrate the method by presenting the theory of potential impurity lattices embedded on chiral p -wave superconductors. While a prerequisite for the topological state engineering is a chiral superconductor, the proposed procedure results in vistas of nontrivial descendant phases with different Chern numbers.

  2. Partial restoration of chiral symmetry in the color flux tube

    CERN Document Server

    Iritani, Takumi; Hashimoto, Shoji

    2015-01-01

    Using the quark eigenmodes computed on the lattice with the overlap-Dirac operator, we investigate the spatial distribution of the chiral condensate around static color sources corresponding to quark-antiquark and three-quark systems. A flux structure of chromo fields appears in the presence of such color charges. The magnitude of the chiral condensate is reduced inside the color flux, which implies partial restoration of chiral symmetry inside hadrons. Taking a static baryon source in a periodic box as a toy model of the nuclear matter, we estimate the magnitude of the chiral symmetry restoration as a function of baryon matter density.

  3. Chiral nucleon-nucleon forces in nuclear structure calculations

    Directory of Open Access Journals (Sweden)

    Coraggio L.

    2016-01-01

    Full Text Available Realistic nuclear potentials, derived within chiral perturbation theory, are a major breakthrough in modern nuclear structure theory, since they provide a direct link between nuclear physics and its underlying theory, namely the QCD. As a matter of fact, chiral potentials are tailored on the low-energy regime of nuclear structure physics, and chiral perturbation theory provides on the same footing two-nucleon forces as well as many-body ones. This feature fits well with modern advances in ab-initio methods and realistic shell-model. Here, we will review recent nuclear structure calculations, based on realistic chiral potentials, for both finite nuclei and infinite nuclear matter.

  4. From enemies to friends: chiral symmetry on the lattice

    International Nuclear Information System (INIS)

    The physics of strong interactions is invariant under the exchange of left-handed and right-handed quarks, at least in the massless limit. This invariance is reflected in the chiral symmetry of quantum chromodynamics. Surprisingly, it has become clear only recently how to implement this important symmetry in lattice formulations of quantum field theories. We will discuss realizations of exact lattice chiral symmetry and give an example of the computation of a physical observable in quantum chromodynamics where chiral symmetry is important. This calculation is performed by relying on finite size scaling methods as predicted by chiral perturbation theory. (orig.)

  5. Single beam optical conveyor belt for chiral particles

    CERN Document Server

    Fernandes, David E

    2016-01-01

    We propose a novel paradigm to selectively manipulate and transport small engineered chiral particles and discriminate different enantiomers using unstructured chiral light. It is theoretically shown that the response of a chiral metamaterial particle may be tailored to enable an optical conveyor belt operation with no optical traps, such that for a fixed incident light helicity and independent of the nanoparticle location, it is either steadily pushed towards the direction of the photon flow or steadily pulled against the photon flow. Our findings create new opportunities for unconventional optical manipulations of tailored nanoparticles and may have applications in sorting racemic mixtures of artificial chiral molecules and in particle delivery.

  6. DSAM lifetime measurements for the chiral pair in 194Tl

    International Nuclear Information System (INIS)

    Most important for the identification of chiral symmetry in atomic nuclei is to establish a pair of bands that are near-degenerate in energy, but also in B(M1) and B(E2) transition probabilities. Dedicated lifetime measurements were performed for four bands of 194Tl, including the pair of four-quasiparticle chiral bands with close near-degeneracy, considered as a prime candidate for best chiral symmetry pair. The lifetime measurements confirm the excellent near-degeneracy in this pair and indicate that a third band may be involved in the chiral symmetry scenario. (orig.)

  7. Enantiomer-Specific State Transfer of Chiral Molecules

    CERN Document Server

    Eibenberger, Sandra; Patterson, David

    2016-01-01

    State-selective enantiomeric excess is realized using microwave-driven coherent population transfer. The method selectively promotes either R- or S- molecules to a higher rotational state by phase-controlled microwave pulses that drive electric-dipole allowed rotational transitions. We demonstrate the method using a racemic mixture of 1,2-propanediol. This method of chiral enrichment can be applied to nearly any chiral molecule that can be vaporized and cooled to the point where rotationally resolved spectroscopy is possible, including molecules that rapidly racemize. The rapid chiral switching demonstrated here allows for new applications in high-precision spectroscopic searches for parity violation in chiral molecules.

  8. Chiral nucleon-nucleon forces in nuclear structure calculations

    CERN Document Server

    Coraggio, L; Holt, J W; Itaco, N; Machleidt, R; Marcucci, L E; Sammarruca, F

    2016-01-01

    Realistic nuclear potentials, derived within chiral perturbation theory, are a major breakthrough in modern nuclear structure theory, since they provide a direct link between nuclear physics and its underlying theory, namely the QCD. As a matter of fact, chiral potentials are tailored on the low-energy regime of nuclear structure physics, and chiral perturbation theory provides on the same footing two-nucleon forces as well as many-body ones. This feature fits well with modern advances in ab-initio methods and realistic shell-model. Here, we will review recent nuclear structure calculations, based on realistic chiral potentials, for both finite nuclei and infinite nuclear matter.

  9. Tunable circular dichroism due to the chiral anomaly in Weyl semimetals

    OpenAIRE

    Hosur, Pavan; Qi, Xiao-Liang

    2014-01-01

    Weyl semimetals are a three dimensional gapless topological phase in which bands intersect at arbitrary points -- the Weyl nodes -- in the Brillouin zone. These points carry a topological quantum number known as the \\emph{chirality} and always appear in pairs of opposite chiralities. The notion of chirality leads to anomalous non-conservation of chiral charge, known as the \\emph{chiral anomaly}, according to which charge can be pumped between Weyl nodes of opposite chiralities by an electroma...

  10. Chiral-particle Approach to Hadrons in an Extended Chiral ($\\sigma,\\pi,\\omega$) Mean-Field Model

    CERN Document Server

    Uechi, Schun T

    2010-01-01

    The chiral nonlinear ($\\sigma,\\pi,\\omega$) mean-field model is an extension of the conserving nonlinear (nonchiral) $\\sigma$-$\\omega$ hadronic mean-field model which is thermodynamically consistent, relativistic and Lorentz-covariant mean-field theory of hadrons. In the extended chiral ($\\sigma,\\pi,\\omega$) mean-field model, all the masses of hadrons are produced by chiral symmetry breaking mechanism, which is different from other conventional chiral partner models. By comparing both nonchiral and chiral mean-field approximations, the effects of chiral symmetry breaking to the mass of $\\sigma$-meson, coefficients of nonlinear interactions, coupling ratios of hyperons to nucleons and Fermi-liquid properties are investigated in nuclear matter, hyperonic matter, and neutron stars.

  11. The effect of the chiral chemical potential on the chiral phase transition in the NJL model with different regularization schemes

    CERN Document Server

    Yu, Lang; Huang, Mei

    2015-01-01

    We study the chiral phase transition in the presence of the chiral chemical potential $\\mu_5$ using the two-flavor Nambu--Jona-Lasinio model. In particular, we analyze the reason why one can obtain two opposite behaviors of the chiral critical temperature as a function of $\\mu_5$ in the framework of different regularization schemes. We compare the modifications of the chiral condensate and the critical temperature due to $\\mu_5$ in different regularization schemes, analytically and numerically. Finally, we find that, for the conventional hard-cutoff regularization scheme, the increasing dependence of the critical temperature on the chiral chemical potential is an artifact, which is caused by the fact that it does not include complete contribution from the thermal fluctuations. When the thermal contribution is fully taken into account, the chiral critical temperature should decrease with $\\mu_5$.

  12. Chiral selection and frequency response of spiral waves in reaction-diffusion systems under a chiral electric field

    Science.gov (United States)

    Li, Bing-Wei; Cai, Mei-Chun; Zhang, Hong; Panfilov, Alexander V.; Dierckx, Hans

    2014-05-01

    Chirality is one of the most fundamental properties of many physical, chemical, and biological systems. However, the mechanisms underlying the onset and control of chiral symmetry are largely understudied. We investigate possibility of chirality control in a chemical excitable system (the Belousov-Zhabotinsky reaction) by application of a chiral (rotating) electric field using the Oregonator model. We find that unlike previous findings, we can achieve the chirality control not only in the field rotation direction, but also opposite to it, depending on the field rotation frequency. To unravel the mechanism, we further develop a comprehensive theory of frequency synchronization based on the response function approach. We find that this problem can be described by the Adler equation and show phase-locking phenomena, known as the Arnold tongue. Our theoretical predictions are in good quantitative agreement with the numerical simulations and provide a solid basis for chirality control in excitable media.

  13. Chiral Perturbation in the Hidden Local Symmetry and Vector Manifestation of Chiral Symmetry

    OpenAIRE

    Harada, Masayasu

    2001-01-01

    In this talk I summarize our recent works on the chiral phase transition in the large flavor QCD studied by the hidden local symmetry (HLS). Bare parameters in the HLS are determined by matching the HLS with the underlying QCD at the matching scale through the Wilsonian matching. This leads to the vector manifestation of the Wigner realization of the chiral symmetry in which the symmetry is restored by the massless degenerate pion (and its flavor partners) and rho meson (and its flavor partne...

  14. Examination of the Potential for Adaptive Chirality of the Nitrogen Chiral Center in Aza-Aspartame

    OpenAIRE

    Samir H. Bouayad-Gervais; William D. Lubell

    2013-01-01

    The potential for dynamic chirality of an azapeptide nitrogen was examined by substitution of nitrogen for the α-carbon of the aspartate residue in the sweetener S,S-aspartame. Considering that S,S- and R,S-aspartame possess sweet and bitter tastes, respectively, a bitter-sweet taste of aza-aspartame 9 could be indicative of a low isomerization barrier for nitrogen chirality inter-conversion. Aza-aspartame 9 was synthesized by a combination of hydrazine and peptide chemistry. Crystallizatio...

  15. Chiral behavior of light meson form factors in 2+1 flavor QCD with exact chiral symmetry

    CERN Document Server

    Kaneko, T; Cossu, G; Feng, X; Fukaya, H; Hashimoto, S; Noaki, J; Onogi, T

    2016-01-01

    We present a study of chiral behavior of light meson form factors in QCD with three flavors of overlap quarks. Gauge ensembles are generated at single lattice spacing 0.12 fm with pion masses down to 300 MeV. The pion and kaon electromagnetic form factors and the kaon semileptonic form factors are precisely calculated using the all-to-all quark propagator. We discuss their chiral behavior using the next-to-next-to-leading order chiral perturbation theory.

  16. True and false chirality, CP violation, and the breakdown of microscopic reversibility in chiral molecular and elementary particle processes

    International Nuclear Information System (INIS)

    The concept of chirality is extended to cover systems that exhibit enantiomorphism on account of motion. This is achieved by applying time reversal in addition to space inversion and leads to a more precise definition of a chiral system. Although spatial enantiomorphism is sufficient to guarantee chirality in a stationary system such as a finite helix, enantiomorphous systems are not necessarily chiral when motion is involved, which leads to the concept of true and false chirality associated with time-invariant and time-noninvariant enantiomorphism, respectively. Only a truly chiral influence can induce an enantiomeric excess in a reaction that has reached true thermodynamic equilibrium (i.e., when all possible interconversion pathways have equilibrated); however, false chirality can suffice in a reaction under kinetic control due to a breakdown of microscopic reversibility analogous to that observed in particle-antiparticle processes involving the neutral K-meason as a result of CP violation, with the apparently contradictory kinetic and thermodynamic aspects being reconciled by an appeal to unitarity. This reveals that CP violation is analogous to chemical catalysis since it affects the rates of certain particle-antiparticle interconversion pathways without affecting the initial and final particle energies and hence the equilibrium thermodynamics. Consideration of falsely chiral influences, including the open-quote ratchet effect close-quote arising from the associated breakdown in microscopic reversibility, greatly enlarges the range of possible chiral advantage factors in prebiotic chemical processes if far from equilibrium. copyright 1996 American Institute of Physics

  17. Molecular-level Design of Heterogeneous Chiral Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Gellman, Andrew John [Carnegie Mellon University; Sholl, David S. [Georgia Institute of Technology; Tysoe, Wilfred T. [University of Wisconsin - Milwaukee; Zaera, Francisco [University of California at Riverside

    2013-04-28

    Understanding and controlling selectivity is one of the key challenges in heterogeneous catalysis. Among problems in catalytic selectivity enantioselectivity is perhaps the most the most challenging. The primary goal of the project on “Molecular-level Design of Heterogeneous Chiral Catalysts” is to understand the origins of enantioselectivity on chiral heterogeneous surfaces and catalysts. The efforts of the project team include preparation of chiral surfaces, characterization of chiral surfaces, experimental detection of enantioselectivity on such surfaces and computational modeling of the interactions of chiral probe molecules with chiral surfaces. Over the course of the project period the team of PI’s has made some of the most detailed and insightful studies of enantioselective chemistry on chiral surfaces. This includes the measurement of fundamental interactions and reaction mechanisms of chiral molecules on chiral surfaces and leads all the way to rationale design and synthesis of chiral surfaces and materials for enantioselective surface chemistry. The PI’s have designed and prepared new materials for enantioselective adsorption and catalysis. Naturally Chiral Surfaces • Completion of a systematic study of the enantiospecific desorption kinetics of R-3-methylcyclohexanone (R-3-MCHO) on 9 achiral and 7 enantiomeric pairs of chiral Cu surfaces with orientations that span the stereographic triangle. • Discovery of super-enantioselective tartaric acid (TA) and aspartic acid (Asp) decomposition as a result of a surface explosion mechanism on Cu(643)R&S. Systematic study of super-enantiospecific TA and Asp decomposition on five enantiomeric pairs of chiral Cu surfaces. • Initial observation of the enantiospecific desorption of R- and S-propylene oxide (PO) from Cu(100) imprinted with {3,1,17} facets by L-lysine adsorption. Templated Chiral Surfaces • Initial observation of the enantiospecific desorption of R- and S-PO from Pt(111) and Pd(111

  18. A novel approach for LC-MS/MS-based chiral metabolomics fingerprinting and chiral metabolomics extraction using a pair of enantiomers of chiral derivatization reagents.

    Science.gov (United States)

    Takayama, Takahiro; Mochizuki, Toshiki; Todoroki, Kenichiro; Min, Jun Zhe; Mizuno, Hajime; Inoue, Koichi; Akatsu, Hiroyasu; Noge, Ichiro; Toyo'oka, Toshimasa

    2015-10-22

    Chiral metabolites are found in a wide variety of living organisms and some of them are understood to be physiologically active compounds and biomarkers. However, the overall analysis of chiral metabolomics is quite difficult due to the high number of metabolites, the significant diversity in their physicochemical properties, and concentration range from metabolite-to-metabolite. To solve this difficulty, we developed a novel approach for chiral metabolomics fingerprinting and chiral metabolomics extraction, which is based on the labeling of a pair of enantiomers of chiral derivatization reagents (i.e., DMT-(S,R)-Pro-OSu and DMT-3(S,R)-Apy) and precursor ion scan chromatography of the derivatives. The multivariate statistics is also required for this strategy. The proposed procedures were evaluated by the detection of a diagnostic marker (i.e., d-lactic acid) using the saliva of diabetic patients. This method was used for the determination of biomarker candidates of chiral amines and carboxyls in Alzheimer's disease (AD) brain homogenates. As the results, l-phenylalanine (L-Phe) and l-lactic acid (L-LA) were identified as the decreased and increased biomarker candidates in the AD brain, respectively. Therefore, the proposed approach seems to be helpful for the determination of non-target chiral metabolomics possessing amines and carboxyls. PMID:26526912

  19. Chiral liquid crystals: the vestigial chiral phases of T, O, I matter

    Science.gov (United States)

    Nissinen, Jaakko; Liu, Ke; Slager, Robert-Jan; Wu, Kai; Zaanen, Jan

    We show how chiral order develops in vestigial isotropic phases of T , O and I liquid crystalline systems in three dimensions. The liquid crystal phases are realized in a lattice model of orientational degrees of freedom with point group symmetries G ⊂ O (3) , represented as O (3) -rotors coupled to G gauge fields. The model incorporates also disclinations via the gauge fields, features an ordered nematic phase with unbroken G rotations at low temperatures and a high temperature isotropic liquid phase. We observe an intermediate phase with spontaneous chirality but isotropic SO (3) symmetry (a liquid) for the gauge groups T, O, and I, the proper symmetry groups of the tetrahedron, cube and icosahedron, respectively. For the other subgroups of SO (3) , Cn <= ∞ and Dn <= ∞, there is generically only a single phase transition from the nematic phase to the isotropic liquid. We discuss the nature of the phase transitions and conditions under which the chiral phase is stabilized by the nematic order parameter fluctuations. The nature of the vestigial chiral phase is reminiscent of the so-called Ising nematic phase in iron based superconductors. Research supported by the Netherlands foundation for Fundamental Research of Matter (FOM).

  20. Supramolecular Chirality: Solvent Chirality Transfer in Molecular Chemistry and Polymer Chemistry

    Directory of Open Access Journals (Sweden)

    Michiya Fujiki

    2014-08-01

    Full Text Available Controlled mirror symmetry breaking arising from chemical and physical origin is currently one of the hottest issues in the field of supramolecular chirality. The dynamic twisting abilities of solvent molecules are often ignored and unknown, although the targeted molecules and polymers in a fluid solution are surrounded by solvent molecules. We should pay more attention to the facts that mostly all of the chemical and physical properties of these molecules and polymers in the ground and photoexcited states are significantly influenced by the surrounding solvent molecules with much conformational freedom through non-covalent supramolecular interactions between these substances and solvent molecules. This review highlights a series of studies that include: (i historical background, covering chiral NaClO3 crystallization in the presence of d-sugars in the late 19th century; (ii early solvent chirality effects for optically inactive chromophores/fluorophores in the 1960s–1980s; and (iii the recent development of mirror symmetry breaking from the corresponding achiral or optically inactive molecules and polymers with the help of molecular chirality as the solvent use quantity.

  1. Synthesis of Chiral Chalcone Derivatives Catalyzed by the Chiral Cinchona Alkaloid Squaramide

    Directory of Open Access Journals (Sweden)

    Dandan Xie

    2014-11-01

    Full Text Available An effective method has been developed for the preparation of novel chiral chalcone derivatives under mild conditions from the easily accessible starting materials nitromethane and chalcone derivatives 2. The corresponding products were obtained in moderate yields with excellent enantioselectivities (up to 99%.

  2. Synthesis of Chiral Chalcone Derivatives Catalyzed by the Chiral Cinchona Alkaloid Squaramide

    OpenAIRE

    Dandan Xie; Ying Xie; Yan Ding; Jian Wu; Deyu Hu

    2014-01-01

    An effective method has been developed for the preparation of novel chiral chalcone derivatives under mild conditions from the easily accessible starting materials nitromethane and chalcone derivatives 2. The corresponding products were obtained in moderate yields with excellent enantioselectivities (up to 99%).

  3. New Chiral Zwitterionic Phosphorus Heterocycles: Synthesis, Structure, Properties and Application as Chiral Solvating Agents

    Czech Academy of Sciences Publication Activity Database

    Sheshenev, A. E.; Boltukhina, E. V.; Grishina, Anastasia; Císařová, I.; Lyapkalo, Ilya; Hii, K. K.

    2013-01-01

    Roč. 19, č. 25 (2013), s. 8136-8143. ISSN 0947-6539 Grant ostatní: 7th European Community Framework Programme(XE) FP7-252247 Institutional support: RVO:61388963 Keywords : binding constants * chirality * enantioselectivity * NMR spectroscopy * phosphorus heterocycles * zwitterions Subject RIV: CC - Organic Chemistry Impact factor: 5.696, year: 2013

  4. The non chiral fusion rules in rational conformal field theories

    CERN Document Server

    Rida, A

    1999-01-01

    We introduce a general method to construct the non chiral fusion rules in rational conformal field theories. We are particularly interested by the models of the complementary series or like-D series which are solutions of modular invariant partition function. The form proposed of the non chiral fusion rules has a structure of Zn grading.

  5. Chiral Boson Theory on the Light-Front

    CERN Document Server

    Srivastava, P P

    1999-01-01

    The {\\it front form} framework for describing the quantized theory of chiral boson is discussed. It avoids the conflict with the requirement of the principle of microcausality as is found in the conventional equal- time treatment. The discussion of the Floreanini-Jackiw model and its modified version for describing the chiral boson becomes very transparent on the light-front.

  6. Nucleon Properties from Approximating Chiral Quark Sigma Model

    CERN Document Server

    Abu-Shady, M

    2009-01-01

    We apply the approximating chiral quark model. This chiral quark model is based on an effective Lagrangian which the interactions between quarks via sigma and pions mesons. The field equations have been solved in the mean field approximation for the hedgehog baryon state. Good results are obtained for nucleon properties in comparison with original model.

  7. Power counting for nuclear forces in chiral effective field theory

    CERN Document Server

    Long, Bingwei

    2016-01-01

    The present note summarizes the discourse on power counting issues of chiral nuclear forces, with an emphasis on renormalization-group invariance. Given its introductory nature, I will lean toward narrating a coherent point of view on the concepts, rather than covering comprehensively the development of chiral nuclear forces in different approaches.

  8. Candidates for Four Quasiparticle Chiral Structures in 126I

    Institute of Scientific and Technical Information of China (English)

    ZHENG; Yun; ZHU; Li-hua; WU; Xiao-guang; GAO; Zao-chun; HE; Chuang-ye; LI; Guang-sheng; WANG; Lie-lin; CHEN; Yong-shou; YU; Bei-bei; YAO; Shun-he; HAO; Xin; LIU; Ying; LI; Xue-qin; PAN; Bo

    2012-01-01

    <正>Since the first prediction of chirality in triaxial nuclei was pointed out by Frauendorf and Meng, nuclei in the A≈80, 100, 130, and 190 mass regions have been extensively studied in recent years to investigate the characteristics of nuclear chirality. Excited states in the doubly odd nucleus 126I were populated via heavy-ion fusion-evaporation

  9. Circular dichroism of graphene oxide: the chiral structure model

    Institute of Scientific and Technical Information of China (English)

    Jing CAO; Hua-Jie YIN; Rui SONG

    2013-01-01

    We have observed the circular dichroism signal of dilute graphene oxide (GO), then systematically investigated the chirality of GO and established a probable chiral unit model, This study may open up a new field for understanding the structure of GO and lay the foundation for fabrication of GO-based materials.

  10. Relation between color-deconfinement and chiral restoration

    OpenAIRE

    Fukushima, Kenji

    2003-01-01

    We discuss the relation between the Polyakov loop and the chiral order parameter at finite temperature by using an effective model. We clarify why and how the pseudo-critical temperature associated with the Polyakov loop should coincide with that of the chiral condensate.

  11. The possible mass region for shears bands and chiral doublets

    Energy Technology Data Exchange (ETDEWEB)

    Meng, J. [Institute of Physical and Chemical Research, Wako, Saitama (Japan); Frauendorf, S.

    1998-03-01

    The Tilted Axis Cranking (TAC) theory is reviewed. The recent progress of TAC for triaxial deformed nuclei is reported. More emphasis has been paid to the new discovered phenomena - chiral doublets and their explanation. The possible mass region for the shears bands and chiral doublets and their experimental signature are discussed. (author)

  12. Long Range Chiral Imprinting of Cu(110) by Tartaric Acid

    Energy Technology Data Exchange (ETDEWEB)

    Lawton, T J; Pushkarev, V; Wei, D; Lucci, F R; Sholl, D S; Gellman, A J; Sykes, E C. H.

    2013-10-31

    Restructuring of metals by chiral molecules represents an important route to inducing and controlling enantioselective surface chemistry. Tartaric acid adsorption on Cu(110) has served as a useful system for understanding many aspects of chiral molecule adsorption and ordering on a metal surface, and a number of chiral and achiral unit cells have been reported. Herein, we show that given the appropriate annealing treatment, singly deprotonated tartaric acid monolayers can restructure the Cu metal itself, and that the resulting structure is both highly ordered and chiral. Molecular resolution scanning tunneling microscopy reveals that singly deprotonated tartaric acid extracts Cu atoms from the Cu(110) surface layer and incorporates them into highly ordered, chiral adatom arrays capped by a continuous molecular layer. Further evidence for surface restructuring comes from images of atom-deep trenches formed in the Cu(110) surface during the process. These trenches also run in low symmetry directions and are themselves chiral. Simulated scanning tunneling microscopy images are consistent with the appearance of the added atom rows and etched trenches. The chiral imprinting results in a long-range, highly ordered unit cell covering the whole surface as confirmed by low energy electron diffraction. Details of the restructuring mechanism were further investigated via time-lapse imaging at elevated temperature. This work reveals the stages of nanoscale surface restructuring and offers an interesting method for chiral modification of an achiral metal surface.

  13. Chiral Pool-Based Synthesis of Naphtho-Fused Isocoumarins.

    Science.gov (United States)

    Raza, Abdul Rauf; Saddiqa, Aisha; Çakmak, Osman

    2015-12-01

    A variety of chiral derivatives of benzo[d]naphtho[1,2-b]pyran-6-one were prepared in a single step by Et3 N-mediated condensation of homophthalic anhydride with different derivatives of (S)-amino acid chlorides at -5 °C by employing a chiral pool methodology. PMID:26441372

  14. pi-pi interaction amplitudes with chiral constraints

    OpenAIRE

    Kaminski, Robert

    2000-01-01

    The pi-pi interaction amplitudes have been calculated using a three coupled channel model both with and without constraints imposed by chiral models. Roy's equations have been used to compare the amplitudes and to study the role played by chiral constraints in the pi-pi interaction.

  15. Hadron Structure Functions within a Chiral Quark Model

    OpenAIRE

    Weigel, H.(Physics Department, Stellenbosch University, Matieland 7602, South Africa); Gamberg, L.(Department of Physics, Penn State University-Berks, Reading, PA, 19610, U.S.A.)

    2000-01-01

    We outline a consistent regularization procedure to compute hadron structure functions within bosonized chiral quark models. We impose the Pauli--Villars scheme, which reproduces the chiral anomaly, to regularize the bosonized action. We derive the Compton amplitude from this action and utilize the Bjorken limit to extract structure functions that are consistent with the scaling laws and sum rules of deep inelastic scattering.

  16. Renormalization of NN Interaction with Relativistic Chiral Two Pion Exchange

    Energy Technology Data Exchange (ETDEWEB)

    Higa, R; Valderrama, M Pavon; Arriola, E Ruiz

    2007-06-14

    The renormalization of the NN interaction with the Chiral Two Pion Exchange Potential computed using relativistic baryon chiral perturbation theory is considered. The short distance singularity reduces the number of counter-terms to about a half as those in the heavy-baryon expansion. Phase shifts and deuteron properties are evaluated and a general overall agreement is observed.

  17. Scalemic and racemic imprinting with a chiral crosslinker.

    Science.gov (United States)

    Hebert, Britney; Meador, Danielle S; Spivak, David A

    2015-08-26

    The development of molecularly imprinted chiral stationary phases has traditionally been limited by the need for a chiral pure template. Paradoxically, availability of a chiral pure template largely defeats the purpose of developing a chiral stationary phase. To solve this paradox, imprinting of scalemic and racemic template mixtures was investigated using both chiral (N-α-bismethacryloyl-L-alanine) and achiral (N,O-bisacrylamide ethanolamine) crosslinkers. Imprinting of scalemic mixtures provided polymers capable of partial separation of Boc-tyrosine enantiomers with virtually the same results when using either the chiral or achiral crosslinker. However, the chiral crosslinker was required for chiral differentiation by the racemic imprinted polymers which were evaluated in both batch rebinding and chromatographic modes. Batch rebinding analysis revealed intersecting binding isotherms for the L- and D-Boc-tyrosine, indicating bias for the D or L enantiomer is concentration dependent. Partial chromatographic separation was achieved by the racemic imprinted polymers providing variable D or L bias in equal probability over multiple replicates of polymer synthesis. Correlation of enantiomer bias with the batch rebinding results and optimization of HPLC parameters are discussed. PMID:26347178

  18. Chiral Stationary Phases Based on Silica Modified by Helicenes

    Czech Academy of Sciences Publication Activity Database

    Bernard, Martin; Církva, Vladimír; Sýkora, Jan; Storch, Jan

    - : -, 2014, s. 74. ISBN N. [Belgian Organic Synthesis Symposium (BOSS XIV) /14./. Louvain-la-Neuve (BE), 13.07.2014-18.07.2014] R&D Projects: GA TA ČR TA01010646 Institutional support: RVO:67985858 Keywords : chiral stationary phase * helicene * chiral resolution Subject RIV: CC - Organic Chemistry

  19. On the overlap formulation of chiral gauge theory

    International Nuclear Information System (INIS)

    The overlap formula proposed by Narayanan and Neuberger in chiral gauge theories is examined. The free chiral and Dirac Green's functions are constructed in this formalism. Four dimensional anomalies are calculated and the usual anomaly cancellation for one standard family of quarks and leptons is verified. (author). 4 refs

  20. Nuclear forces from chiral EFT: The unfinished business

    OpenAIRE

    Machleidt, R.; Entem, D.R.

    2010-01-01

    In spite of the great progress we have seen in recent years in the derivation of nuclear forces from chiral effective field theory (EFT), some important issues are still unresolved. In this contribution, we discuss the open problems which have particular relevance for microscopic nuclear structure, namely, the proper renormalization of chiral nuclear potentials and sub-leading many-body forces.

  1. Dirac Bracket Quantization of Bosonized chiral QCD2

    International Nuclear Information System (INIS)

    We systematically derive the bosonized form of the chiral QCD2 Zagrangean exchibiting explicitely the anomalous breaking of gauge invariance and quantize it using Dirac's algorithm for constrained systems. As a side product we also discuss the Hamiltonean formalism for the principal sigma model, and derive the commutation relations of the chiral currents in both models. (author)

  2. Lagrangian Formulation of the General Modified Chiral Model

    OpenAIRE

    Ioannidou, Theodora; Zakrzewski, Wojtek

    1998-01-01

    We present a Lagrangian formulation for the general modified chiral model. We use it to discuss the Hamiltonian formalism for this model and to derive the commutation relations for the chiral field. We look at some explicit examples and show that the Hamiltonian, containing a contribution involving a Wess-Zumino term, is conserved, as required.

  3. Hidden symmetry of the two-dimensional chiral fields

    International Nuclear Information System (INIS)

    The non-Abelian Goldstone boson (chiral field) interaction in two dimensions is examined. As was shown earlier, this theory strongly resembles the Yang-Mills theory in four dimensions. It is shown that dynamics of chiral fields is governed by the infinite number of the non-trivial conservation laws, which impose strong limitations on the S matrix. (Auth.)

  4. Spontaneous transmission of chirality through multiple length scales.

    Science.gov (United States)

    Iski, Erin V; Tierney, Heather L; Jewell, April D; Sykes, E Charles H

    2011-06-20

    The hierarchical transfer of chirality in nature, from the nano-, to meso-, to macroscopic length scales, is very complex, and as of yet, not well understood. The advent of scanning probes has allowed chirality to be monitored at the single molecule or monolayer level and has opened up the possibility to track enantiospecific interactions and chiral self-assembly with molecular-scale detail. This paper describes the self-assembly of a simple, model molecule (naphtho[2,3-a]pyrene) that is achiral in the gas phase, but becomes chiral when adsorbed on a surface. This polyaromatic hydrocarbon forms a stable and reversibly ordered system on Cu(111) in which the transmission of chirality from single surface-bound molecules to complex 2D chiral architectures can be monitored as a function of molecular packing density and surface temperature. In addition to the point chirality of the surface-bound molecule, the unit cell of the molecular domains was also found to be chiral due to the incommensurate alignment of the molecular rows with respect to the underlying metal lattice. These molecular domains always aggregated in groups of three, all of the same chirality, but with different rotational orientations, forming homochiral "tri-lobe" ensembles. At a larger length scale, these tri-lobe ensembles associated with nearest-neighbor tri-lobe units of opposite chirality at lower packing densities before forming an extended array of homochiral tri-lobe ensembles at higher converges. This system displayed chirality at a variety of size scales from the molecular (≈1 nm) and domain (≈5 nm) to the tri-lobe ensemble (≈10 nm) and extended array (>25 nm) levels. The chirality of the tri-lobe ensembles dictated how the overall surface packing occurred and both homo- and heterochiral arrays could be reproducibly and reversibly formed and interchanged as a function of surface coverage. Finally, these chirally templated surfaces displayed remarkable enantiospecificity for

  5. Chiral properties of dynamical Wilson fermions

    International Nuclear Information System (INIS)

    Quantum Chromodynamics with two light quark flavors is considered in the lattice regularization with improved Wilson fermions. In this formulation chiral symmetry is explicitly broken by cutoff effects linear in the lattice spacing a. As a consequence the isovector axial currents require improvement (in the Symanzik sense) as well as a finite renormalization if they are to satisfy the continuum Ward-Takahashi identities associated with the isovector chiral symmetries up to small lattice corrections of O(a2). In exploratory numerical simulations of the lattice theory algorithmic difficulties were encountered at coarse lattice spacings. There the hybrid Monte Carlo algorithm used suffers from a distorted Dirac spectrum in the form of unphysically small eigenvalues. This is shown to be a cutoff effect, which disappears rapidly as the lattice spacing is decreased. An alternative algorithm, the polynomial hybrid Monte Carlo algorithm, is found to perform significantly better in the presence of exceptionally small eigenvalues. Extending previously used methods both the improvement and the renormalization of the axial current are implemented non-perturbatively in terms of correlation functions formulated in the framework of the Schroedinger functional. In both cases this is achieved by enforcing continuum Ward identities at finite lattice spacing. Together, this restores the isovector chiral symmetry to quadratic order in the lattice spacing. With little additional effort the normalization factor of the local vector current is also obtained. The methods developed and implemented here can easily be applied to other actions formulated in the Schroedinger functional framework. This includes improved gauge actions as well as theories with more than two dynamical quark flavors. (orig.)

  6. Some aspects of chirality: Fermion masses and chiral p-forms

    International Nuclear Information System (INIS)

    The properties of fermion mass matrices are investigated from different points of view, both within the minimal Standard Model and in extensions of the model. It is shown how mass matrix invariants are used to define the measurables of the quark mixing matrix as invariant functions of the mass matrices. One model is presented where the family pattern is suggested to originate from a kind of mass scaling. A Lagrangian density is defined for an entire charge sector, such that the existence of a Dirac field with mass m0 implies the existence of other Dirac fields where the corresponding quanta have masses Rm0, R2m0, .. which are obtained by a discrete scale transformation. This suggests a certain type of democratic fermion mass matrices. Also extensions of the minimal Standard Model are investigated, obtained by including right-handed neutrinos in the model. The Standard Model extended by two right-handed neutrinos gives rise to a mass spectrum with two massive and three massless neutrinos. The phenomenological consequences of this model are discussed. The neutrino mass matrix in such a scheme has what is defined as a democratic texture. They are studied for the cases with two and three right-handed neutrinos, resp. The chiral fields that we find in the Standard Model have certain similarities with self-dual fields. Among other things, both chiral and self-dual fields suffer species doubling on the lattice. Chiral p-forms are self-dual fields that appear in twice odd dimensions. Chiral p-forms violate manifest covariance, in the same sense as manifest covariance is violated by non-covariant gauges in electrodynamics. It is shown that a covariant action can nevertheless be formulated for chiral p-forms, by introducing an infinite set of gauge fields in a carefully controlled way

  7. Some aspects of chirality: Fermion masses and chiral p-forms

    Energy Technology Data Exchange (ETDEWEB)

    Kleppe, A.

    1997-05-01

    The properties of fermion mass matrices are investigated from different points of view, both within the minimal Standard Model and in extensions of the model. It is shown how mass matrix invariants are used to define the measurables of the quark mixing matrix as invariant functions of the mass matrices. One model is presented where the family pattern is suggested to originate from a kind of mass scaling. A Lagrangian density is defined for an entire charge sector, such that the existence of a Dirac field with mass m{sub 0} implies the existence of other Dirac fields where the corresponding quanta have masses Rm{sub 0}, R{sup 2}m{sub 0}, .. which are obtained by a discrete scale transformation. This suggests a certain type of democratic fermion mass matrices. Also extensions of the minimal Standard Model are investigated, obtained by including right-handed neutrinos in the model. The Standard Model extended by two right-handed neutrinos gives rise to a mass spectrum with two massive and three massless neutrinos. The phenomenological consequences of this model are discussed. The neutrino mass matrix in such a scheme has what is defined as a democratic texture. They are studied for the cases with two and three right-handed neutrinos, resp. The chiral fields that we find in the Standard Model have certain similarities with self-dual fields. Among other things, both chiral and self-dual fields suffer species doubling on the lattice. Chiral p-forms are self-dual fields that appear in twice odd dimensions. Chiral p-forms violate manifest covariance, in the same sense as manifest covariance is violated by non-covariant gauges in electrodynamics. It is shown that a covariant action can nevertheless be formulated for chiral p-forms, by introducing an infinite set of gauge fields in a carefully controlled way.

  8. Magnetic fields and chiral asymmetry in the early hot universe

    CERN Document Server

    Sidorenko, Maxim; Shtanov, Yuri

    2016-01-01

    In this paper, we study analytically the process of external generation and subsequent free evolution of the lepton chiral asymmetry and helical magnetic fields in the early hot universe. This process is known to be affected by the Abelian anomaly of the electroweak gauge interactions. As a consequence, chiral asymmetry in the fermion distribution generates magnetic fields of non-zero helicity, and vice versa. We take into account the presence of thermal bath, which serves as a seed for the development of instability in magnetic field in the presence of externally generated lepton chiral asymmetry. The developed helical magnetic field and lepton chiral asymmetry support each other, considerably prolonging their mutual existence, in the process of 'inverse cascade' transferring magnetic-field power from small to large spatial scales. For cosmologically interesting initial conditions, the chiral asymmetry and the energy density of helical magnetic field are shown to evolve by scaling laws, effectively depending...

  9. Lateral shifting in one dimensional chiral photonic crystal

    International Nuclear Information System (INIS)

    We report the lateral shifts of the transmitted waves in a one dimensional chiral photonic crystal by using the stationary-phase approach. It is revealed that two kinds of lateral shifts are observed due to the existence of cross coupling in chiral materials, which is different from what has been observed in previous non-chiral photonic crystals. Unlike the chiral slab, the positions of lateral shift peaks are closely related to the band edges of band gap characteristics of periodic structure and lateral shifts can be positive as well as negative. Besides, the lateral shifts show a strong dependence on the chiral factor, which varies the lateral shift peaks in both magnitudes and positions. These features are desirable for future device applications.

  10. A new approach to chiral fermions on the lattice

    International Nuclear Information System (INIS)

    We wish to describe a method for formulating, on the lattice, field theories that contain Dirac particles with chiral couplings to gauge fields. As is well-known, the most straight-forward lattice transcription of the continuum action for a Dirac particle leads to the doubling problem: for every particle of a given chirality in the continuum theory, there appear on the lattice, in d dimensions, 2d particles, with equal numbers of particles of left- and right-handed chirality. No-go theorems, state that it is impossible to eliminate the doubling problem and still maintain an exact chiral gauge symmetry. Rather than follow an approach that attempts to circumvent the no-go theorems we, instead, explore the possibility of abandoning exact chiral symmetry

  11. Hyperfine meson splittings: chiral symmetry versus transverse gluon exchange

    CERN Document Server

    Llanes-Estrada, Felipe J; Swanson, Eric S; Szczepaniak, Adam P; Llanes-Estrada, Felipe J.; Cotanch, Stephen R.; Szczepaniak, Adam P.; Swanson, Eric S.

    2004-01-01

    Meson spin splittings are examined within an effective Coulomb gauge QCD Hamiltonian incorporating chiral symmetry and a transverse hyperfine interaction necessary for heavy quarks. For light and heavy quarkonium systems the pseudoscalar-vector meson spectrum is generated by approximate BCS-RPA diagonalizations. This relativistic formulation includes both $S$ and $D$ waves for the vector mesons which generates a set of coupled integral equations. A smooth transition from the heavy to the light quark regime is found with chiral symmetry dominating the $\\pi$-$\\rho$ mass difference. A good, consistent description of the observed meson spin splittings and chiral quantities, such as the quark condensate and the $\\pi$ mass, is obtained. Similar comparisons with TDA diagonalizations, which violate chiral symmetry, are deficient for light pseudoscalar mesons indicating the need to simultaneously include both chiral symmetry and a hyperfine interaction. The $\\eta_b$ mass is predicted to be around 9400 MeV consistent w...

  12. Chiral organic glass and its infrared spectrum property

    Institute of Scientific and Technical Information of China (English)

    陶卫东; 夏海平; 董建峰; 白贵儒; 聂秋华; 陆祖康

    2003-01-01

    Chiral molecules griseofulvin were disseminated homogeneously in poly methyl metahcrylate (PMMA) host, which agglomerate from methyl metahcrylate and N, N-dimethyl formamide dimethyl acetal, using benzoyl peroxide as a catalyst. So the chiral organic glass has been manufactured successfully. Its optical rotatory were investigated from a solution state to a solid state. The results of measurement show that the chiral parameter of the chiral organic glass is 2.65×10-7 and its specific rotation has increased compared with its solution condition. Its infrared spectra property has been measured by Fourier transformation infrared spectrometer. The results show that the chiral molecules fill in the pore of the network structure in the organic glass, which hardly link with the host.

  13. Spontaneous chiral symmetry breaking in collective active motion

    Science.gov (United States)

    Breier, Rebekka E.; Selinger, Robin L. B.; Ciccotti, Giovanni; Herminghaus, Stephan; Mazza, Marco G.

    2016-02-01

    Chiral symmetry breaking is ubiquitous in biological systems, from DNA to bacterial suspensions. A key unresolved problem is how chiral structures may spontaneously emerge from achiral interactions. We study a simple model of active swimmers in three dimensions that effectively incorporates hydrodynamic interactions. We perform large-scale molecular dynamics simulations (up to 106 particles) and find long-lived metastable collective states that exhibit chiral organization although the interactions are achiral. We elucidate under which conditions these chiral states will emerge and grow to large scales. To explore the complex phase space available to the system, we perform nonequilibrium quenches on a one-dimensional Lebwohl-Lasher model with periodic boundary conditions to study the likelihood of formation of chiral structures.

  14. Synthesis of novel chiral compounds of purine and pyrimidine bases

    Institute of Scientific and Technical Information of China (English)

    汪毓海; 陈庆华

    1999-01-01

    The physiologically active groups such as purine and pyrimidine bases are introduced to the asymmetric ynthesis. The optically pure compounds bearing purine and pyrimidine bases (5a—5e) were prepared via the asymetric Michael addition reaction of purines and pyrimidines as Michael donators with the chiral source 5-(R)-[(1R, 2S, 5R)-menthyloxy]-2(5H)-furanone (3a), which was prepared from the natural chiral auxiliary (-)-menthol. The synthetic method was studied in detail and the new compounds were identified on the basis of their analytical data and spectroscopic data, such as [α]D20, IR, UV, 1H NMR, 13C NMR and MS. The absolute configuration of 5a was established by X-ray crystallography. The results provided an efficient synthetic route to chiral purines and pyrimidine analogues, and offered chiral sources for further research on the physiologically active compounds of chiral nucleotides.

  15. Inhomogeneous chiral symmetry breaking in dense neutron-star matter

    CERN Document Server

    Buballa, Michael

    2015-01-01

    An increasing number of model results suggests that chiral symmetry is broken inhomogeneously in a certain window at intermediate densities in the QCD phase diagram. This could have significant effects on the properties of compact stars, possibly leading to new astrophysical signatures. In this contribution we discuss this idea by reviewing recent results on inhomogeneous chiral symmetry breaking under an astrophysics-oriented perspective. After introducing two commonly studied spatial modulations of the chiral condensate, the chiral density wave and the real kink crystal, we focus on their properties and their effect on the equation of state of quark matter. We also describe how these crystalline phases are affected by different elements which are required for a realistic description of a compact star, such as charge neutrality, the presence of magnetic fields, vector interactions and the interplay with color-superconductivity. Finally, we discuss possible signatures of inhomogeneous chiral symmetry breaking...

  16. Microstructure effects for Casimir forces in chiral metamaterials

    International Nuclear Information System (INIS)

    We examine a recent prediction for the chirality dependence of the Casimir force in chiral metamaterials by numerical computation of the forces between the exact microstructures, rather than homogeneous approximations. Although repulsion in the metamaterial regime is rigorously impossible, it is unknown whether a reduction in the attractive force can be achieved through suitable material engineering. We compute the exact force for a chiral bent-cross pattern, as well as forces for an idealized ''omega''-particle medium in the dilute approximation and identify the effects of structural inhomogeneity (i.e., proximity forces and anisotropy). We find that these microstructure effects dominate the force for separations where chirality was predicted to have a strong influence. At separations where the homogeneous approximation is valid, in even the most ideal circumstances the effects of chirality are less than 10-4 of the total force, making them virtually undetectable in experiments.

  17. Helical polyacetylene synthesized with a chiral nematic reaction field

    Science.gov (United States)

    Akagi; Piao; Kaneko; Sakamaki; Shirakawa; Kyotani

    1998-11-27

    Helical polyacetylene was synthesized under an asymmetric reaction field consisting of chiral nematic (N*) liquid crystals (LCs). The chiral nematic LC was prepared by adding a chiroptical binaphthol derivative as a chiral dopant to a mixture of two nematic LCs. Acetylene polymerizations were carried out using the catalyst titanium tetra-n-butoxide-triethylaluminum dissolved in the chiral nematic LC solvent. The polyacetylene film was shown by scanning electron microscopy to consist of clockwise or counterclockwise helical structure of fibrils. A Cotton effect was observed in the region of the pi --> pi* transition of the polyacetylene chain in circular dichroism spectra. The high electrical conductivities of approximately 1500 to 1800 siemens per centimeter after iodine doping and the chiral helicity of these films may be exploited in electromagnetic and optical applications. PMID:9831554

  18. Chiral rings and anomalies in supersymmetric gauge theory

    International Nuclear Information System (INIS)

    Motivated by recent work of Dijkgraaf and Vafa, we study anomalies and the chiral ring structure in a supersymmetric U(N) gauge theory with an adjoint chiral superfield and an arbitrary superpotential. A certain generalization of the Konishi anomaly leads to an equation which is identical to the loop equation of a bosonic matrix model. This allows us to solve for the expectation values of the chiral operators as functions of a finite number of 'integration constants'. From this, we can derive the Dijkgraaf-Vafa relation of the effective superpotential to a matrix model. Some of our results are applicable to more general theories. For example, we determine the classical relations and quantum deformations of the chiral ring of N=1 super Yang-Mills theory with SU(N) gauge group, showing, as one consequence, that all supersymmetric vacua of this theory have a nonzero chiral condensate. (author)

  19. Chirality in block copolymer melts: mesoscopic helicity from intersegment twist.

    Science.gov (United States)

    Zhao, Wei; Russell, Thomas P; Grason, Gregory M

    2013-02-01

    We study the effects of chirality at the segment scale on the thermodynamics of block copolymer melts using self-consistent field theory. In linear diblock melts where segments of one block prefer a twisted, or cholesteric, texture, we show that melt assembly is critically sensitive to the ratio of random coil size to the preferred pitch of cholesteric twist. For weakly chiral melts (large pitch), mesophases remain achiral, while below a critical value of pitch, two mesoscopically chiral phases are stable: an undulated lamellar phase and a phase of hexagonally ordered helices. We show that the nonlinear sensitivity of mesoscale chiral order to preferred pitch derives specifically from the geometric and thermodynamic coupling of the helical mesodomain shape to the twisted packing of chiral segments within the core, giving rise to a second-order cylinder-to-helix transition. PMID:23414052

  20. Chiroptical studies on supramolecular chirality of molecular aggregates.

    Science.gov (United States)

    Sato, Hisako; Yajima, Tomoko; Yamagishi, Akihiko

    2015-10-01

    The attempts of applying chiroptical spectroscopy to supramolecular chirality are reviewed with a focus on vibrational circular dichroism (VCD). Examples were taken from gels, solids, and monolayers formed by low-molecular mass weight chiral gelators. Particular attention was paid to a group of gelators with perfluoroalkyl chains. The effects of the helical conformation of the perfluoroalkyl chains on the formation of chiral architectures are reported. It is described how the conformation of a chiral gelator was determined by comparing the experimental and theoretical VCD spectra together with a model proposed for the molecular aggregation in fibrils. The results demonstrate the potential utility of the chiroptical method in analyzing organized chiral aggregates. PMID:26183570