U1 small nuclear RNA variants differentially form ribonucleoprotein particles in vitro.
Somarelli, Jason A; Mesa, Annia; Rodriguez, Carol E; Sharma, Shalini; Herrera, Rene J
2014-04-25
The U1 small nuclear (sn)RNA participates in splicing of pre-mRNAs by recognizing and binding to 5' splice sites at exon/intron boundaries. U1 snRNAs associate with 5' splice sites in the form of ribonucleoprotein particles (snRNPs) that are comprised of the U1 snRNA and 10 core components, including U1A, U1-70K, U1C and the 'Smith antigen', or Sm, heptamer. The U1 snRNA is highly conserved across a wide range of taxa; however, a number of reports have identified the presence of expressed U1-like snRNAs in multiple species, including humans. While numerous U1-like molecules have been shown to be expressed, it is unclear whether these variant snRNAs have the capacity to form snRNPs and participate in splicing. The purpose of the present study was to further characterize biochemically the ability of previously identified human U1-like variants to form snRNPs and bind to U1 snRNP proteins. A bioinformatics analysis provided support for the existence of multiple expressed variants. In vitro gel shift assays, competition assays, and immunoprecipitations (IPs) revealed that the variants formed high molecular weight assemblies to varying degrees and associated with core U1 snRNP proteins to a lesser extent than the canonical U1 snRNA. Together, these data suggest that the human U1 snRNA variants analyzed here are unable to efficiently bind U1 snRNP proteins. The current work provides additional biochemical insights into the ability of the variants to assemble into snRNPs. Copyright © 2014 Elsevier B.V. All rights reserved.
Cajal bodies and snRNPs friends with benefits
Czech Academy of Sciences Publication Activity Database
Staněk, David
2017-01-01
Roč. 14, č. 6 (2017), s. 671-679 ISSN 1547-6286 R&D Projects: GA ČR GA15-00790S Institutional support: RVO:68378050 Keywords : spinal muscular-atrophy * small nuclear-rna * u4/u6.u5 tri-snrnp * xenopus-laevis oocytes * u6 spliceosomal rna * coiled bodies * smn complex * u1 snrnp * u2 snrnp * in-vivo Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Cell biology Impact factor: 3.900, year: 2016
International Nuclear Information System (INIS)
Chang, Chia-Feng; Ma, Ernest; Yuan, Tzu-Chiang
2015-01-01
In this talk we will explore the possibility of adding a local U(1) dark sector to the standard model with the Higgs boson as a portal connecting the visible standard model sector and the dark one. We will discuss existing experimental constraint on the model parameters from the invisible width of Higgs decay. Implications of such a dark U(1) sector on phenomenology at the Large Hardon Collider will be addressed. In particular, detailed results for the non-standard signals of multi-lepton-jets that arise from this simple dark sector will be presented. (paper)
Energy Technology Data Exchange (ETDEWEB)
McDougall, N.A. (Oxford Univ. (UK). Dept. of Theoretical Physics)
1984-08-23
The resolution of the U(1) problem requires the quark condensates to have a specific THETA dependence. We show that the required THETA dependence arises naturally upon application of the index theorem during the calculation of the dynamically generated quark mass.
Biliński, Szczepan M; Kloc, Małgorzata
2002-03-01
Oocytes of certain insects contain peculiar organelles termed accessory nuclei (AN). These organelles originate by budding off from the envelope of the oocyte nucleus and contain 1-2 dense inclusions immersed in a translucent ground substance. We have demonstrated that in the wasp Vespula germanica each inclusion consists of two elements: a spherical body, and a hemispherical structure composed of numerous 20-30 nm particles. Immunoelectron microscopy and whole-mount in situ hybridization have shown that the inclusions contain AgNOR-staining proteins, p80-coilin, Sm proteins, and small nuclear RNAs (snRNAs). These results indicate that the inclusions and hemispherical structures are homologous to Cajal bodies and B-snurposomes of Xenopus germinal vesicles, respectively. During previtellogenesis, AN (together with their Cajal bodies) migrate to the cortical ooplasm of the oocyte where they reside at least until the onset of embryogenesis. We suggest that AN are vehicles for the transport and localization of snRNPs to the periphery of the oocyte, i.e., to the region where the blastoderm of the embryo develops and where there is a requirement for a high concentration of RNA-processing factors.
Lee, Hyun Min
2018-03-01
We consider the gauged U (1) clockwork theory with a product of multiple gauge groups and discuss the continuum limit of the theory to a massless gauged U (1) with linear dilaton background in five dimensions. The localization of the lightest state of gauge fields on a site in the theory space naturally leads to exponentially small effective couplings of external matter fields localized away from the site. We discuss the implications of our general discussion with some examples, such as mediators of dark matter interactions, flavor-changing B-meson decays as well as D-term SUSY breaking.
International Nuclear Information System (INIS)
McDougall, N.A.
1984-01-01
The resolution of the U(1) problem requires the quark condensates to have a specific THETA dependence. We show that the required THETA dependence arises naturally upon application of the index theorem during the calculation of the dynamically generated quark mass. (orig.)
Functional organization of the Sm core in the crystal structure of human U1 snRNP.
Weber, Gert; Trowitzsch, Simon; Kastner, Berthold; Lührmann, Reinhard; Wahl, Markus C
2010-12-15
U1 small nuclear ribonucleoprotein (snRNP) recognizes the 5'-splice site early during spliceosome assembly. It represents a prototype spliceosomal subunit containing a paradigmatic Sm core RNP. The crystal structure of human U1 snRNP obtained from natively purified material by in situ limited proteolysis at 4.4 Å resolution reveals how the seven Sm proteins, each recognize one nucleotide of the Sm site RNA using their Sm1 and Sm2 motifs. Proteins D1 and D2 guide the snRNA into and out of the Sm ring, and proteins F and E mediate a direct interaction between the Sm site termini. Terminal extensions of proteins D1, D2 and B/B', and extended internal loops in D2 and B/B' support a four-way RNA junction and a 3'-terminal stem-loop on opposite sides of the Sm core RNP, respectively. On a higher organizational level, the core RNP presents multiple attachment sites for the U1-specific 70K protein. The intricate, multi-layered interplay of proteins and RNA rationalizes the hierarchical assembly of U snRNPs in vitro and in vivo.
International Nuclear Information System (INIS)
Pan Feng
1991-01-01
VCS representations of SO 5 contains SU 2 + SU 2 contains U 1 + U 1 and SO 5 contains U 1 + U 1 are discussed. Reduced matrix elements for SO 5 contains SU 2 + SU 2 are derived. The multiplicity of a weight for SO 5 is determined by using the K-matrix technique
U(1) x U(1) x U(1) symmetry of the Kimura 3ST model and phylogenetic branching processes
International Nuclear Information System (INIS)
Bashford, J D; Jarvis, P D; Sumner, J G; Steel, M A
2004-01-01
An analysis of the Kimura 3ST model of DNA sequence evolution is given on the basis of its continuous Lie symmetries. The rate matrix commutes with a U(1) x U(1) x U(1) phase subgroup of the group GL(4) of 4 x 4 invertible complex matrices acting on a linear space spanned by the four nucleic acid base letters. The diagonal 'branching operator' representing speciation is defined, and shown to intertwine the U(1) x U(1) x U(1) action. Using the intertwining property, a general formula for the probability density on the leaves of a binary tree under the Kimura model is derived, which is shown to be equivalent to established phylogenetic spectral transform methods. (letter to the editor)
U(1) mediation of flux supersymmetry breaking
Grimm, Thomas W.; Klemm, Albrecht
2008-10-01
We study the mediation of supersymmetry breaking triggered by background fluxes in Type II string compactifications with Script N = 1 supersymmetry. The mediation arises due to an U(1) vector multiplet coupling to both a hidden supersymmetry breaking flux sector and a visible D-brane sector. The required internal manifolds can be constructed by non-Kähler resolutions of singular Calabi-Yau manifolds. The effective action encoding the U(1) coupling is then determined in terms of the global topological properties of the internal space. We investigate suitable local geometries for the hidden and visible sector in detail. This includes a systematic study of orientifold symmetries of del Pezzo surfaces realized in compact geometries after geometric transition. We construct compact examples admitting the key properties to realize flux supersymmetry breaking and U(1) mediation. Their toric realization allows us to analyze the geometry of curve classes and confirm the topological connection between the hidden and visible sector.
U(1) mediation of flux supersymmetry breaking
International Nuclear Information System (INIS)
Grimm, Thomas W.; Klemm, Albrecht
2008-01-01
We study the mediation of supersymmetry breaking triggered by background fluxes in Type II string compactifications with N = 1 supersymmetry. The mediation arises due to an U(1) vector multiplet coupling to both a hidden supersymmetry breaking flux sector and a visible D-brane sector. The required internal manifolds can be constructed by non-Kaehler resolutions of singular Calabi-Yau manifolds. The effective action encoding the U(1) coupling is then determined in terms of the global topological properties of the internal space. We investigate suitable local geometries for the hidden and visible sector in detail. This includes a systematic study of orientifold symmetries of del Pezzo surfaces realized in compact geometries after geometric transition. We construct compact examples admitting the key properties to realize flux supersymmetry breaking and U(1) mediation. Their toric realization allows us to analyze the geometry of curve classes and confirm the topological connection between the hidden and visible sector.
O(5) x U(1) electroweak theory
International Nuclear Information System (INIS)
Mukku, C.; Sayed, W.A.
1980-12-01
An anomaly free O(5) x U(1) theory of electroweak interactions is described which provides a unified description of electroweak phenomena for two families of standard leptons and quarks. No ''new'' non-sequential type fermions of the standard model are introduced as has been the case for all past studies based on this group. The present scheme requires the introduction of two further charged and three more neutral gauge fields over and above the Wsup(+-), Z and photon fields of SU(2) x U(1) giving rise to new neutral and charged currents. In this note we outline our reasons for proposing the present electroweak scheme, give the basic structure of the model, discuss the symmetry breaking pattern which ensures that SU(2)sub(L) x U(1) is the low energy symmetry, point out the new interactions present in the extended framework and obtain limits on the masses of all the gauge fields. (author)
Topological excitations in U(1) -invariant theories
International Nuclear Information System (INIS)
Savit, R.
1977-01-01
A class of U(1) -invariant theories in d dimensions is introduced on a lattice. These theories are labeled by a simplex number s, with 1 < or = s < d. The case with s = 1 is the X-Y model; and s = 2 gives compact photodynamics. An exact duality transformation is applied to show that the U(1) -invariant theory in d dimensions with simplex number s is the same as a similar theory in d dimensions but which is Z /sub infinity/-invariant and has simplex number s = d-s. This dual theory describes the topological excitations of the original theory. These excitations are of dimension s - 1
O(5) x U(1) electroweak theory
International Nuclear Information System (INIS)
Mukku, C.; Sayed, W.A.
1981-01-01
An anomaly-free O(5) x U(1) theory of electroweak interactions is described which provides a unified description of electroweak phenomena for two families of standard leptons and quarks. No ''new'' nonsequential-type fermions are introduced, unlike the case for all past studies based on this group. The present scheme requires the introduction of two further charged and three more neutral gauge fields over and above those of SU(2) x U(1) giving rise to new neutral and charged currents
Two-dimensional gauge model with vector U(1) and axial-vector U(1) symmetries
International Nuclear Information System (INIS)
Watabiki, Y.
1989-01-01
We have succeeded in constructing a two-dimensional gauge model with both vector U(1) and axial-vector U(1) symmetries. This model is exactly solvable. The Schwinger term vanishes in this model as a consequence of the above symmetries, and negative-norm states appear. However, the norms of physical states are always positive semidefinite due to the gauge symmetries
Deletion of SNURF/SNRPN U1B and U1B* upstream exons in a ...
Indian Academy of Sciences (India)
RESEARCH ARTICLE. Deletion of SNURF/SNRPN U1B and U1B* upstream exons in a child ... whereby genes are expressed in a parent-of-origin dependent manner. One of the ... lity, neurodevelopmental delay, features of attention deficit hyperactivity .... Received 16 December 2015; accepted 8 January 2016. Unedited ...
More modular invariant anomalous U(1) breaking
International Nuclear Information System (INIS)
Gaillard, Mary K.; Giedt, Joel
2002-01-01
We consider the case of several scalar fields, charged under a number of U(1) factors, acquiring vacuum expectation values due to an anomalous U(1). We demonstrate how to make redefinitions at the superfield level in order to account for tree-level exchange of vector supermultiplets in the effective supergravity theory of the light fields in the supersymmetric vacuum phase. Our approach builds upon previous results that we obtained in a more elementary case. We find that the modular weights of light fields are typically shifted from their original values, allowing an interpretation in terms of the preservation of modular invariance in the effective theory. We address various subtleties in defining unitary gauge that are associated with the noncanonical Kaehler potential of modular invariant supergravity, the vacuum degeneracy, and the role of the dilaton field. We discuss the effective superpotential for the light fields and note how proton decay operators may be obtained when the heavy fields are integrated out of the theory at the tree-level. We also address how our formalism may be extended to describe the generalized Green-Schwarz mechanism for multiple anomalous U(1)'s that occur in four-dimensional Type I and Type IIB string constructions
U(1) textures and Lepton Flavor Violation
Gómez, M E; Lola, S; Vergados, J D
1999-01-01
U(1) family symmetries have led to successful predictions of the fermion mass spectrum and the mixing angles of the hadronic sector. In the context of the supersymmetric unified theories, they further imply a non-trivial mass structure for the scalar partners, giving rise to new sources of flavour violation. In the present work, lepton flavour non-conserving processes are examined in the context of the MSSM augmented by a U(1) family symmetry. We calculate the mixing effects on the mu -> e gamma and tau-> mu gamma rare decays. All supersymmetric scalar masses involved in the processes are determined at low energies using two loop renormalisation group analysis and threshold corrections. Further, various novel effects are considered and found to have important impact on the branching ratios. Thus, a rather interesting result is that when the see-saw mechanism is applied in the (12X12)-sneutrino mass matrix, the mixing effects of the Dirac matrix in the effective light sneutrino sector are canceled at first ord...
Flipped SU(5) times U(1) in superconformal models
Energy Technology Data Exchange (ETDEWEB)
Bailin, D.; Katechou, E.K. (Sussex Univ., Brighton (United Kingdom). School of Mathematical and Physical Sciences); Love, A. (London Univ. (United Kingdom))
1992-01-10
This paper reports that flipped SU(5) {times} U(1) models are constructed in the framework of tensoring of N = 2 superconformal minimal models quotiented by discrete symmetries. Spontaneous breaking of flipped SU(5) {times} U(1) and extra U(1) factors in the gauge group along F-flat directions of the effective potential is studied.
SU(2) x U(1) x U'(1) models which are slightly different from the Weinberg-Salam model
International Nuclear Information System (INIS)
Gao, C.; Wu, D.
1981-01-01
We discuss SU(2) x U(1) x U'(1) models by a uniform formula which is convenient for their comparison with the standard Weinberg-Salam model. As examples, we give three interesting models which are based on different grand unification models. In one model, U'(1) does not contribute to the electromagnetic interaction; in the other two, both U(1) and U'(1) do contribute to the electromagnetic interaction. Also, the first two models can approach the standard Weinberg-Salam model as close as one wants; but the third model has limitations on it
Light hidden-sector U(1)s in string compactifications
Energy Technology Data Exchange (ETDEWEB)
Goodsell, Mark; Ringwald, Andreas
2010-02-15
We review the case for light U(1) gauge bosons in the hidden-sector of heterotic and type II string compactifications, present estimates of the size of their kinetic mixing with the visible-sector hypercharge U(1), and discuss their possibly very interesting phenomenological consequences in particle physics and cosmology. (orig.)
Light hidden-sector U(1)s in string compactifications
International Nuclear Information System (INIS)
Goodsell, Mark; Ringwald, Andreas
2010-02-01
We review the case for light U(1) gauge bosons in the hidden-sector of heterotic and type II string compactifications, present estimates of the size of their kinetic mixing with the visible-sector hypercharge U(1), and discuss their possibly very interesting phenomenological consequences in particle physics and cosmology. (orig.)
Gauge U(1 dark symmetry and radiative light fermion masses
Directory of Open Access Journals (Sweden)
Corey Kownacki
2016-09-01
Full Text Available A gauge U(1 family symmetry is proposed, spanning the quarks and leptons as well as particles of the dark sector. The breaking of U(1 to Z2 divides the two sectors and generates one-loop radiative masses for the first two families of quarks and leptons, as well as all three neutrinos. We study the phenomenological implications of this new connection between family symmetry and dark matter. In particular, a scalar or pseudoscalar particle associated with this U(1 breaking may be identified with the 750 GeV diphoton resonance recently observed at the Large Hadron Collider (LHC.
Supersymmetric U boson and the old U(1) problem
International Nuclear Information System (INIS)
Kim, B.R.
1983-01-01
In the supersymmetric SU(3)xSU(2)xU(1)xUsup(')(1) model the new gauge group Usup(')(1) enforces the introduction of mirror fermions. In this note we address the inverse question. If one starts with SU(3)xSU(2)xU(1) including mirror fermions, what physical arguments other than the supersymmetric require the introduction of a new gauge group Usup(')(1). It turns out that the old U(1) problem is closely related with this question. Further we give an estimate for the upper bound for the parameter of the supersymmetric U boson r and x. (orig.)
Isoforms of U1-70k control subunit dynamics in the human spliceosomal U1 snRNP.
Directory of Open Access Journals (Sweden)
Helena Hernández
2009-09-01
Full Text Available Most human protein-encoding genes contain multiple exons that are spliced together, frequently in alternative arrangements, by the spliceosome. It is established that U1 snRNP is an essential component of the spliceosome, in human consisting of RNA and ten proteins, several of which are post-translationally modified and exist as multiple isoforms. Unresolved and challenging to investigate are the effects of these post translational modifications on the dynamics, interactions and stability of the particle. Using mass spectrometry we investigate the composition and dynamics of the native human U1 snRNP and compare native and recombinant complexes to isolate the effects of various subunits and isoforms on the overall stability. Our data reveal differential incorporation of four protein isoforms and dynamic interactions of subunits U1-A, U1-C and Sm-B/B'. Results also show that unstructured post-translationally modified C-terminal tails are responsible for the dynamics of Sm-B/B' and U1-C and that their interactions with the Sm core are controlled by binding to different U1-70k isoforms and their phosphorylation status in vivo. These results therefore provide the important functional link between proteomics and structure as well as insight into the dynamic quaternary structure of the native U1 snRNP important for its function.
A SU(3) x U(1) model for electroweak interactions
International Nuclear Information System (INIS)
Pisano, F.; Pleitez, V.
1992-01-01
We consider a gauge model based on a SU(3) vector U(1) symmetry in which the lepton number is violated explicitly by charged scalar and gauge boson, including a vector field with double electric charge. (author)
Anomalous U(1) as a mediator of Supersymmetry Breaking
Dvali, Gia; Dvali, Gia; Pomarol, Alex
1996-01-01
We point out that an anomalous gauge U(1) symmetry is a natural candida= te for being the mediator and messenger of supersymmetry breaking. It facilitate= s dynamical supersymmetry breaking even in the flat limit. Soft masses are induced by both gravity and the U(1) gauge interactions giving an unusual= mass hierarchy in the sparticle spectrum which suppresses flavor violations. T= his scenario does not suffer from the Polonyi problem.
Underground storage tank 291-D1U1: Closure plan
Energy Technology Data Exchange (ETDEWEB)
Mancieri, S.; Giuntoli, N.
1993-09-01
The 291-D1U1 tank system was installed in 1983 on the north side of Building 291. It supplies diesel fuel to the Building 291 emergency generator and air compressor. The emergency generator and air compressor are located southwest and southeast, respectively, of the tank (see Appendix B, Figure 2). The tank system consists of a single-walled, 2,000- gallon, fiberglass tank and a fuel pump system, fill pipe, vent pipe, electrical conduit, and fuel supply and return piping. The area to be excavated is paved with asphalt and concrete. It is not known whether a concrete anchor pad is associated with this tank. Additionally, this closure plan assumes that the diesel tank is below the fill pad. The emergency generator and air compressor for Building 291 and its associated UST, 291-D1U1, are currently in use. The generator and air compressor will be supplied by a temporary above-ground fuel tank prior to the removal of 291-D1U1. An above-ground fuel tank will be installed as a permanent replacement for 291-D1U1. The system was registered with the State Water Resources Control Board on June 27, 1984, as 291-41D and has subsequently been renamed 291-D1U1. Figure 1 (see Appendix B) shows the location of the 291-D1U1 tank system in relation to the Lawrence Livermore National Laboratory (LLNL). Figure 2 (see Appendix B) shows the 291-D1U1 tank system in relation to Building 291. Figure 3 (see Appendix B) shows a plan view of the 291-D1U1 tank system.
Energy Technology Data Exchange (ETDEWEB)
Mihajlovic, A; Djuric, B; Tepavac, P [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Yugoslavia)
1965-11-15
Study of continuous cooling of the U-1% Mo alloy is significant if it could be used as fuel in the nuclear reactor. Previous studies were dealing with relatively low cooling rate up to 3 deg C/s{sup 1}, which produced alpha + gamma structure. This task was devoted to testing the U-1% Mo alloy properties at higher cooling rates in order to discover whether bainite reaction and favourable alpha grain could be achieved under certain conditions.
F-GUTs with Mordell-Weil U(1)'s
Antoniadis, I
2014-01-01
In this note we study the constraints on F-theory GUTs with extra $U(1)$'s in the context of elliptic fibrations with rational sections. We consider the simplest case of one abelian factor (Mordell-Weil rank one) and investigate the conditions that are induced on the coefficients of its Tate form. Converting the equation representing the generic hypersurface $P_{112}$ to this Tate's form we find that the presence of a U(1), already in this local description, is consistent with the exceptional ${\\cal E}_6$ and ${\\cal E}_7$ non-abelian singularities. We briefly comment on a viable ${\\cal E}_6\\times U(1)$ effective F-theory model.
Minimal anomalous U(1) theories and collider phenomenology
Ekstedt, Andreas; Enberg, Rikard; Ingelman, Gunnar; Löfgren, Johan; Mandal, Tanumoy
2018-02-01
We study the collider phenomenology of a neutral gauge boson Z ' arising in minimal but anomalous U(1) extensions of the Standard Model (SM). To retain gauge invariance of physical observables, we consider cancellation of gauge anomalies through the Green-Schwarz mechanism. We categorize a wide class of U(1) extensions in terms of the new U(1) charges of the left-handed quarks and leptons and the Higgs doublet. We derive constraints on some benchmark models using electroweak precision constraints and the latest 13 TeV LHC dilepton and dijet resonance search data. We calculate the decay rates of the exotic and rare one-loop Z ' decays to ZZ and Z-photon modes, which are the unique signatures of our framework. If observed, these decays could hint at anomaly cancellation through the Green-Schwarz mechanism. We also discuss the possible observation of such signatures at the LHC and at future ILC colliders.
A model with isospin doublet U(1)D gauge symmetry
Nomura, Takaaki; Okada, Hiroshi
2018-05-01
We propose a model with an extra isospin doublet U(1)D gauge symmetry, in which we introduce several extra fermions with odd parity under a discrete Z2 symmetry in order to cancel the gauge anomalies out. A remarkable issue is that we impose nonzero U(1)D charge to the Standard Model Higgs, and it gives the most stringent constraint to the vacuum expectation value of a scalar field breaking the U(1)D symmetry that is severer than the LEP bound. We then explore relic density of a Majorana dark matter candidate without conflict of constraints from lepton flavor violating processes. A global analysis is carried out to search for parameters which can accommodate with the observed data.
A reduction of the globalization and U(1)-covering
International Nuclear Information System (INIS)
Tran Dao Dong.
1993-03-01
We suggest a reduction of the globalization and multidimensional quantization to the case of reductive Lie groups by lifting to U(1)-covering. our construction is connected with M. Duflo's third method for algebraic groups. From a reductive datum of the given real algebraic Lie group we firstly construct geometric complexes with respect to U(1)-covering by using the unipotent positive distributions. Then we describe in terms of local cohomology the maximal globalization of Harish-Chandra modules which correspond to the geometric complexes. (author). 9 refs
Implications of Anomalous U(1) Symmetry in Unified Models the Flipped SU(5) x U(1) Paradigm
Ellis, Jonathan Richard; Rizos, J; Ellis, John
2000-01-01
A generic feature of string-derived models is the appearance of an anomalousAbelian U(1)_A symmetry which, among other properties, constrains the Yukawacouplings and distinguishes the three families from each other. In this paper,we discuss in a model-independent way the general constraints imposed by such aU(1)_A symmetry on fermion masses, R-violating couplings and proton-decayoperators in a generic flipped SU(5) x U(1)' model. We construct all possibleviable fermion mass textures and give various examples of effective low-energymodels which are distinguished from each other by their different predictionsfor B-, L- and R-violating effects. We pay particular attention to predictionsfor neutrino masses, in the light of the recent Super-Kamiokande data.
Fractional winding numbers and the U(1) problem
International Nuclear Information System (INIS)
Rothe, K.D.; Swieca, J.A.; Pontificia Univ. Catolica do Rio de Janeiro
1980-06-01
The effective Lagrangian description of gauge theories with spontaneous mass generation is simulated by considering the chiral Gross-Neveu model embedded in a two-dimensional U(1) gauge theory. It is shown that in this hybrid model the non-vanishing expectation value of psi psi is due to the contribution of instanton configurations with fractional winding. (Author) [pt
Rational conformal theories involving a U(1) current algebra
International Nuclear Information System (INIS)
Todorov, I.T.
1989-01-01
The problem of constructing and classifying rational conformal theories is illustrated on the example of extended chiral algebras involving a single U(1) current. The bulk of the paper is a self contained review (with some improvements) of recent work of R. Paunov and the author. (author)
Anomalous U(1)A and electroweak symmetry breaking
International Nuclear Information System (INIS)
Gogoladze, I.; Tsulaya, M.
2000-01-01
A new mechanism for electroweak symmetry breaking in the supersymmetric Standard Model is suggested. Our suggestion is based on the presence of an anomalous U(1) A gauge symmetry, which naturally arises in the four-dimensional superstring theory, and heavily relies on the corresponding Fayet-Illiopoulos ξ-term
Anomalous U(1)A and electroweak symmetry breaking
International Nuclear Information System (INIS)
Gogoladze, Ilia
2000-10-01
We suggest a mechanism for electroweak symmetry breaking in the Supersymmetric Standard Model. Our suggestion is based on the presence of an anomalous U(1) A gauge symmetry, which naturally arises in the four dimensional superstring theory, and heavily relies on the value of the corresponding Fayet-Illiopoulos ξ-term. (author)
The U(1) Higgs model in an external electromagnetic field
International Nuclear Information System (INIS)
Damgaard, P.H.; Heller, U.M.
1988-01-01
An external electromagnetic field is coupled to the lattice-regularized U(1) Higgs model. We study the phase diagram of this model by both analytical and numerical techniques for different values of the external field strength tensor. The results are compared with expectations based on the analogy with superconducting systems, as described by the phenomenological Ginzburg-Landau theory. (orig.)
Interactions between $U(1)$ Cosmic Strings: An Analytical Study
Bettencourt, L. M. A.; Rivers, R. J.
1994-01-01
We derive analytic expressions for the interaction energy between two general $U(1)$ cosmic strings as the function of their relative orientation and the ratio of the coupling constants in the model. The results are relevant to the statistic description of strings away from critical coupling and shed some light on the mechanisms involved in string formation and the evolution of string networks.
Kinetic Mixing of U(1)s in Heterotic Orbifolds
Goodsell, Mark; Ringwald, Andreas
2012-01-01
We study kinetic mixing between massless U(1) gauge symmetries in the bosonic formulation of heterotic orbifold compactifications. For non-prime Z_N factorisable orbifolds, we find a simple expression of the mixing in terms of the properties of the N=2 subsectors, which helps understand under what conditions mixing can occur. With this tool, we analyse Z_6-II heterotic orbifolds and find non-vanishing mixing even without including Wilson lines. We show that some semi-realistic models of the Mini-Landscape admit supersymmetric vacua with mixing between the hypercharge and an additional U(1), which can be broken at low energies. We finally discuss some phenomenologically appealing possibilities that hidden photons in heterotic orbifolds allow.
SU(4) x U(1) gauge theory. II. CP nonconservation
International Nuclear Information System (INIS)
Deshpande, N.G.; Hwa, R.C.; Mannheim, P.D.
1979-01-01
We exploit the higher symmetry inherent in an SU(4) x U(1) gauge theory to construct a spontaneously broken theory of CP nonconservation. Higgs multiplets in the adjoint representation of SU(4) contain both even and odd CP fields; thus, requiring the simultaneous nonvanishing of the vacuum expectation values of these fields leads to CP noninvariance of the vacuum. We find that all the CP-nonconserving effects are mediated in our theory by the superheavy gauge bosons of the broken SU(4) x U(1) symmetry. In fact, the very existence of CP violation sets an upper limit on the masses of these bosons. In our model the dominant CP effect lies in the neutral kaon system and is found to arise through a direct (ΔS = 2) K 1 -K 2 transition. The model has all the features of a superweak theory, with a neutron electric dipole moment substantially smaller than 10 -24 e cm
Kinetic mixing of U(1)s in heterotic orbifolds
Energy Technology Data Exchange (ETDEWEB)
Goodsell, Mark [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Ramos-Sanchez, Saul [UNAM, Mexico (Mexico). Dept. of Theoretical Physics; Ringwald, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2011-10-15
We study kinetic mixing between massless U(1) gauge symmetries in the bosonic formulation of heterotic orbifold compactifications. For non-prime Z{sub N} factorisable orbifolds, we find a simple expression of the mixing in terms of the properties of the N=2 subsectors, which helps understand under what conditions mixing can occur. With this tool, we analyse Z{sub 6}-II heterotic orbifolds and find non-vanishing mixing even without including Wilson lines. We show that some semi-realistic models of the Mini-Landscape admit supersymmetric vacua with mixing between the hypercharge and an additional U(1), which can be broken at low energies. We finally discuss some phenomenologically appealing possibilities that hidden photons in heterotic orbifolds allow. (orig.)
Underground storage tank 431-D1U1, Closure Plan
Energy Technology Data Exchange (ETDEWEB)
Mancieri, S.
1993-09-01
This document contains information about the decommissioning of Tank 431-D1U1. This tank was installed in 1965 for diesel fuel storage. This tank will remain in active usage until closure procedures begin. Soils and ground water around the tank will be sampled to check for leakage. Appendices include; proof of proper training for workers, health and safety briefing record, task hazard analysis summary, and emergency plans.
More flipped SU(5) x U(1) baryosynthesis
Energy Technology Data Exchange (ETDEWEB)
Ellis, J.; Hagelin, J.S.; Nanopoulos, D.V.; Olive, K.A.
1988-06-30
We supplement a previous discussion of baryosynthesis in flipped SU(5)xU(1) GUTs by including (1) the large incoherent field energy density which is likely when SU(5) is broken, and (2) the possibility of additional Higgs triplet fields suggested by four-dimensional string model-building. We consider strong (weak) reheating scenarios in which the Universe is (is not) SU(5) symmetric after inflation. We find an adequate baryon asymmetry subsequent to strong reheating, whatever the number of Higgs triplets (although beware of possible difficulties with quasi-stable relic particles), whereas weak reheating requires at least two Higgs triplets.
Gaugino radiative decay in an anomalous U(1)' model
International Nuclear Information System (INIS)
Lionetto, Andrea; Racioppi, Antonio
2010-01-01
We study the neutralino radiative decay into the lightest supersymmetric particle (LSP) in the framework of a minimal anomalous U(1) ' extension of the MSSM. It turns out that in a suitable decoupling limit the axino, which is present in the Stueckelberg multiplet, is the LSP. We compute the branching ratio (BR) for the decay of a neutralino into an axino and a photon. We find that in a wide region of the parameter space, the BR is higher than 93% in contrast with the typical value (≤1%) in the CMSSM.
Supersymmetric U(1)' model with multiple dark matters
International Nuclear Information System (INIS)
Hur, Taeil; Lee, Hye-Sung; Nasri, Salah
2008-01-01
We consider a scenario where a supersymmetric model has multiple dark matter particles. Adding a U(1) ' gauge symmetry is a well-motivated extension of the minimal supersymmetric standard model (MSSM). It can cure the problems of the MSSM such as the μ problem or the proton decay problem with high-dimensional lepton number and baryon number violating operators which R parity allows. An extra parity (U parity) may arise as a residual discrete symmetry after U(1) ' gauge symmetry is spontaneously broken. The lightest U-parity particle (LUP) is stable under the new parity becoming a new dark matter candidate. Up to three massive particles can be stable in the presence of the R parity and the U parity. We numerically illustrate that multiple stable particles in our model can satisfy both constraints from the relic density and the direct detection, thus providing a specific scenario where a supersymmetric model has well-motivated multiple dark matters consistent with experimental constraints. The scenario provides new possibilities in the present and upcoming dark matter searches in the direct detection and collider experiments
Implications of hidden gauged U (1 ) model for B anomalies
Fuyuto, Kaori; Li, Hao-Lin; Yu, Jiang-Hao
2018-06-01
We propose a hidden gauged U (1 )H Z' model to explain deviations from the standard model (SM) values in lepton flavor universality known as RK and RD anomalies. The Z' only interacts with the SM fermions via their mixing with vectorlike doublet fermions after the U (1 )H symmetry breaking, which leads to b →s μ μ transition through the Z' at tree level. Moreover, introducing an additional mediator, inert-Higgs doublet, yields b →c τ ν process via charged scalar contribution at tree level. Using flavio package, we scrutinize adequate sizes of the relevant Wilson coefficients to these two processes by taking various flavor observables into account. It is found that significant mixing between the vectorlike and the second generation leptons is needed for the RK anomaly. A possible explanation of the RD anomaly can also be simultaneously addressed in a motivated situation, where a single scalar operator plays a dominant role, by the successful model parameters for the RK anomaly.
Light U(1) gauge boson coupled to baryon number
International Nuclear Information System (INIS)
Carone, C.D.; Murayama, Hitoshi
1995-06-01
The authors discuss the phenomenology of a light U(1) gauge boson, γ B , that couples only to baryon number. Gauging baryon number at high energies can prevent dangerous baryon-number violating operators that may be generated by Planck scale physics. However, they assume at low energies that the new U(1) gauge symmetry is spontaneously broken and that the γ B mass m B is smaller than m z . They show for m Υ B z that the γB coupling α B can be as large as ∼ 0.1 without conflicting with the current experimental constraints. The authors argue that α B ∼ 0.1 is large enough to produce visible collider signatures and that evidence for the γ B could be hidden in existing LEP data. They show that there are realistic models in which mixing between the γ B and the electroweak gauge bosons occurs only as a radiative effect and does not lead to conflict with precision electroweak measurements. Such mixing may nevertheless provide a leptonic signal for models of this type at an upgraded Tevatron
Confinement in dually transformed U(1) lattice gauge theory
International Nuclear Information System (INIS)
Zach, M.
1997-10-01
The aim of this work is a detailed investigation of the confinement mechanism in U(1) lattice gauge theory. In the first chapters we give a review on the definition of compact Abelian gauge theory on space-time lattices, the numerical calculation of physical observables for exploring confinement, and the interpretation of the results in terms of the dual superconductor picture, which is introduced at two levels of description. We work out that the electric field strength and the magnetic currents around a charge pair can be described very well by a classical effective model of Maxwell and London equations, if fluctuations of the occurring fluxoid string are considered. In order to obtain a deeper understanding of confinement in U(1), we extend the duality transformation of the path integral to the correlation functions which are used to calculate expectation values of fields and currents. This not only helps to interpret U(1) lattice gauge theory as a limit of the dual Higgs model, but also opens the possibility for efficient calculations of expectation values in the presence of static charges by simulating the dual model. Using this technique we are able to consider large flux tube lengths, low temperatures, and multiply charged systems without loss of numerical precision. The dual simulation is applied to flux tubes between static charges, to periodically closed flux tubes (torelons), and to doubly charged systems. We find that the behavior of flux tubes for large charge distances cannot be explained by the picture of a classical dual type-II superconductor; the observed roughening of the flux tube agrees very well with the prediction from the effective string description. We also analyze the different contributions to the total energy of the electromagnetic field. For torelons we calculate both the free energy and the total field energy, split the free energy into a string tension and a string fluctuation part, and apply lattice sum rules modified for finite
e +e- modes and U(1) spontaneous chiral symmetry breaking
International Nuclear Information System (INIS)
Steininger, K.
1992-01-01
In this paper, motivated by evidence for a chiral phase transition in strong coupling lattice QED, the authors calculate the two-particle spectrum of the broken QED phase. This is done in the framework of a Nambu and Jona-Lasinio model with U(1) symmetry including chiral symmetry and symmetry breaking properties of QED. The second order chiral phase transition behavior in our model and in lattice QED are in excellent agreement. The authors then present a detailed analysis of the spectra of the e + e - modes in the broken phase. The authors examine whether these modes have any possible relationship to the narrow e + e - resonances found in soft heavy ion collisions at GSL. The authors' answer is negative
U(1)' dark matter and R-parity violation
International Nuclear Information System (INIS)
Brahm, D.E.
1990-04-01
Attempts to understand physics beyond the Standard Model must face many phenomenological constraint, from recent Z degree data, neutral current measurements, cosmology and astrophysics, neutrino experiments, tests of lepton-and baryon-number conservation and CP violation, and many other ongoing experiments. The most interesting models are those which are allowed by current data, but offer predictions which can soon be experimentally confirmed or refuted. Two classes of such models are explored in this dissertation. The first, containing an extra U(1)' gauge group, has a dark matter candidate which could soon be detected. The second, incorporating supersymmetry with R-parity violation, predicts rare Z degree decays at LEP; some of these models can already be ruled out by LEP data and gluino searches at the Tevatron. 54 refs., 31 figs
Absence of U(1) anomalous superamplitudes in N≥5 supergravities
Energy Technology Data Exchange (ETDEWEB)
Freedman, Daniel Z. [Stanford Institute for Theoretical Physics and Department of Physics, Stanford University,Stanford, CA 94305 (United States); Center for Theoretical Physics and Department of Mathematics,Massachusetts Institute of Technology,Cambridge, MA 02139 (United States); Kallosh, Renata; Murli, Divyanshu [Stanford Institute for Theoretical Physics and Department of Physics, Stanford University,Stanford, CA 94305 (United States); Proeyen, Antoine Van [KU Leuven, Institute for Theoretical Physics,Celestijnenlaan 200D, B-3001, Leuven (Belgium); Yamada, Yusuke [Stanford Institute for Theoretical Physics and Department of Physics, Stanford University,Stanford, CA 94305 (United States)
2017-05-12
We list all potential candidates for U(1) anomalous non-local 1-loop 4-point amplitudes and higher loop UV divergences in N≥5 supergravities. The relevant chiral superinvariants are constructed from linearized chiral superfields and define the corresponding superamplitudes. The anomalous amplitudes, of the kind present in N=4, are shown to be absent in N≥5. In N=6 supergravity the result is deduced from the double-copy (N=4){sub YM}×(N=2){sub YM} model, whereas in N=5,8 the result on absence of anomalous amplitudes is derived in supergravities as well as in the (N=4){sub YM}×(N−4){sub YM} double-copy models.
On the BRST cohomology in U(1) gauge theory
International Nuclear Information System (INIS)
Malik, R.P.
1998-08-01
We discuss the Becchi-Rouet-Stora-Tyutin (BRST) cohomology in the case of two-dimensional free U(1) gauge theory. In addition to the usual BRST charge, we deduce a conserved and nilpotent dual-BRST charge under which the gauge-fixing term remains invariant. This charge is the analogue of the adjoint (dual) exterior derivative of differential geometry. The BRST extended Casimir operator, corresponding to the Laplacian operator of differential geometry, turns out to generate a symmetry under which the ghost term remains invariant. We take a single photon state in the Hilbert space and demonstrate the notion of gauge invariance, no-(anti)ghost theorem and transversality of photon by exploiting the refinement of cohomology by selecting the physical state as the harmonic state of the Hodge decomposition theorem. (author)
Noncommutative U(1) gauge theory from a worldline perspective
Energy Technology Data Exchange (ETDEWEB)
Ahmadiniaz, Naser [Facultad de Ciencias en Física y Matemáticas, Universidad Autónoma de Chiapas,Ciudad Universitaria, Tuxtla Gutiérrez 29050 (Mexico); Corradini, Olindo [Facultad de Ciencias en Física y Matemáticas, Universidad Autónoma de Chiapas,Ciudad Universitaria, Tuxtla Gutiérrez 29050 (Mexico); Dipartimento di Scienze Fisiche, Informatiche e Matematiche,Università di Modena e Reggio Emilia,Via Campi 213/A, I-41125 Modena (Italy); D’Ascanio, Daniela [Instituto de Física La Plata - CONICET, Universidad Nacional de La Plata,CC 67 (1900), La Plata (Argentina); Estrada-Jiménez, Sendic [Facultad de Ciencias en Física y Matemáticas, Universidad Autónoma de Chiapas,Ciudad Universitaria, Tuxtla Gutiérrez 29050 (Mexico); Pisani, Pablo [Instituto de Física La Plata - CONICET, Universidad Nacional de La Plata,CC 67 (1900), La Plata (Argentina)
2015-11-10
We study pure noncommutative U(1) gauge theory representing its one-loop effective action in terms of a phase space worldline path integral. We write the quadratic action using the background field method to keep explicit gauge invariance, and then employ the worldline formalism to write the one-loop effective action, singling out UV-divergent parts and finite (planar and non-planar) parts, and study renormalization properties of the theory. This amounts to employ worldline Feynman rules for the phase space path integral, that nicely incorporate the Fadeev-Popov ghost contribution and efficiently separate planar and non-planar contributions. We also show that the effective action calculation is independent of the choice of the worldline Green’s function, that corresponds to a particular way of factoring out a particle zero-mode. This allows to employ homogeneous string-inspired Feynman rules that greatly simplify the computation.
U(1) prime dark matter and R-parity violation
Energy Technology Data Exchange (ETDEWEB)
Brahm, D.E.
1990-04-01
Attempts to understand physics beyond the Standard Model must face many phenomenological constraint, from recent Z{sup {degree}} data, neutral current measurements, cosmology and astrophysics, neutrino experiments, tests of lepton-and baryon-number conservation and CP violation, and many other ongoing experiments. The most interesting models are those which are allowed by current data, but offer predictions which can soon be experimentally confirmed or refuted. Two classes of such models are explored in this dissertation. The first, containing an extra U(1){prime} gauge group, has a dark matter candidate which could soon be detected. The second, incorporating supersymmetry with R-parity violation, predicts rare Z{sup {degree}} decays at LEP; some of these models can already be ruled out by LEP data and gluino searches at the Tevatron. 54 refs., 31 figs.
Holism and structuralism in U(1) gauge theory
Lyre, Holger
After decades of neglect philosophers of physics have discovered gauge theories-arguably the paradigm of modern field physics-as a genuine topic for foundational and philosophical research. Incidentally, in the last couple of years interest from the philosophy of physics in structural realism-in the eyes of its proponents the best suited realist position towards modern physics-has also raised. This paper tries to connect both topics and aims to show that structural realism gains further credence from an ontological analysis of gauge theories-in particular U (1) gauge theory. In the first part of the paper the framework of fiber bundle gauge theories is briefly presented and the interpretation of local gauge symmetry will be examined. In the second part, an ontological underdetermination of gauge theories is carved out by considering the various kinds of non-locality involved in such typical effects as the Aharonov-Bohm effect. The analysis shows that the peculiar form of non-separability figuring in gauge theories is a variant of spatiotemporal holism and can be distinguished from quantum theoretic holism. In the last part of the paper the arguments for a gauge theoretic support of structural realism are laid out and discussed.
Extended U(1) conformal field theories and Zk-parafermions
International Nuclear Information System (INIS)
Furlan, P.; Paunov, R.R.; Todorov, I.T.
1992-01-01
A constructive approach is developed for studying local chiral algebras generated by a pair of oppositely charged fields ψ(z, ±g) such that the operator product expansion (OPE) of ψ(z 1 ,g) ψ(z 2 , -g) involves a U (1) current. The main tool in the study is the factorization property of the charged fields (exhibited in [PT 2.3]) for Virasoro central charge c k -parafermions. The case Δ 2 =4(Δ 1 -1), where Δ sν =Δ K-ν (Δ 0 =0) ore conformal dimensions of the parafemionic currents, is studied in detail. For Δ Τ = 2Τ(1 - Δ/k) the theory is related to GEPNER'S [GE] Z 2 [SO (k)] parafermions and the corresponding quantum field theroretic (QFT) representations of the chiral algebra are displayed. The Coulomb gas method of [CR] is further developed to include an explicit construction of the basic parafermionic current φ of wight Δ = Δ 1 . The characters of the positive energy representations of the local chiral algebra are written as sums of products of Kac,s string functions and classical Θ-functions. (orig.)
U(1) Wilson lattice gauge theories in digital quantum simulators
Muschik, Christine; Heyl, Markus; Martinez, Esteban; Monz, Thomas; Schindler, Philipp; Vogell, Berit; Dalmonte, Marcello; Hauke, Philipp; Blatt, Rainer; Zoller, Peter
2017-10-01
Lattice gauge theories describe fundamental phenomena in nature, but calculating their real-time dynamics on classical computers is notoriously difficult. In a recent publication (Martinez et al 2016 Nature 534 516), we proposed and experimentally demonstrated a digital quantum simulation of the paradigmatic Schwinger model, a U(1)-Wilson lattice gauge theory describing the interplay between fermionic matter and gauge bosons. Here, we provide a detailed theoretical analysis of the performance and the potential of this protocol. Our strategy is based on analytically integrating out the gauge bosons, which preserves exact gauge invariance but results in complicated long-range interactions between the matter fields. Trapped-ion platforms are naturally suited to implementing these interactions, allowing for an efficient quantum simulation of the model, with a number of gate operations that scales polynomially with system size. Employing numerical simulations, we illustrate that relevant phenomena can be observed in larger experimental systems, using as an example the production of particle-antiparticle pairs after a quantum quench. We investigate theoretically the robustness of the scheme towards generic error sources, and show that near-future experiments can reach regimes where finite-size effects are insignificant. We also discuss the challenges in quantum simulating the continuum limit of the theory. Using our scheme, fundamental phenomena of lattice gauge theories can be probed using a broad set of experimentally accessible observables, including the entanglement entropy and the vacuum persistence amplitude.
VG2 URA TRAJECTORY DERIVED SUMM U1 COORDS 48SEC V1.0
National Aeronautics and Space Administration — This dataset contains Voyager 2 spacecraft position vectors relative to Uranus in minus U1 coordinates. The U1 or Uranus West Longitude System coordinate system is a...
Dark Matter candidate in Inert Doublet Model with additional local gauge symmetry U (1)
International Nuclear Information System (INIS)
Gaitán, R.; De Oca, J.H. Montes; Garcés, E. A.; Cabral-Rosetti, L. G.
2016-01-01
We consider the Inert Doublet Model (IDM) with an additional local gauge symmetry U (1) and a complex singlet scalar to break the symmetry U (1). The continuous symmetry U (1) is introduced to control the CP-conserving interaction instead of some discrete symmetries as usually. We present the mass spectrum for neutral scalar and gauge bosons and the values of the charges under U (1) for which the model could have a candidate to dark matter. (paper)
Light sterile neutrinos, dark matter, and new resonances in a U(1) extension of the MSSM
Hebbar, A.; Lazarides, G.; Shafi, Q.
2017-09-01
We present ψ'MSSM, a model based on a U(1) ψ' extension of the minimal supersymmetric standard model. The gauge symmetry U(1)ψ', also known as U(1)N,is a linear combination of the U(1) χ and U(1)ψ subgroups of E6. The model predicts the existence of three sterile neutrinos with masses ≲0.1 eV , if the U(1)ψ' breaking scale is of order 10 TeV. Their contribution to the effective number of neutrinos at nucleosynthesis is Δ Nν≃0.29. The model can provide a variety of possible cold dark matter candidates including the lightest sterile sneutrino. If the U(1) ψ' breaking scale is increased to 1 03 TeV , the sterile neutrinos, which are stable on account of a Z2symmetry, become viable warm dark matter candidates. The observed value of the standard model Higgs boson mass can be obtained with relatively light stop quarks thanks to the D-term contribution from U(1)ψ'. The model predicts diquark and diphoton resonances which may be found at an updated LHC. The well-known μ problem is resolved and the observed baryon asymmetry of the universe can be generated via leptogenesis. The breaking of U(1)ψ' produces superconducting strings that may be present in our galaxy. A U(1) R symmetry plays a key role in keeping the proton stable and providing the light sterile neutrinos.
Klinar, Walter J.; Berman, Theodore
1948-01-01
An investigation has been conducted in the Langley 20-foot free-spinning tunnel on the 1/20-scale model of the Chance Vought XF6U-1 airplane altered to represent the XF6U-1 airplane as it will be spin-tested in flight, and also altered to represent the F6U-1 airplane as it will be produced for service use. Spin tests were made to determine the effects of control settings and movements at the normal loading. The results show that the spins obtained on the revised XF6U-1 airplane will be oscillatory in roll and yaw and that recoveries by rudder reversal will be rapid. Model test results indicate that the F6U-1 airplane will probably not spin. Inasmuch as the results of this investigation show that the new designs are as good as or better than the original XF6U-1 design in regard to spin recovery, it is felt that the conclusions and recommendations reached for the original design can be applied to the new designs for all loading conditions.
Single field inflation in supergravity with a U(1) gauge symmetry
Energy Technology Data Exchange (ETDEWEB)
Heurtier, L. [Centre de Physique Théorique, École Polytechnique, CNRS, 91128 Palaiseau (France); Khalil, S.; Moursy, A., E-mail: lucien.heurtier@polytechnique.edu, E-mail: skhalil@zewailcity.edu.eg, E-mail: amoursy@zewailcity.edu.eg [Center for Fundamental Physics, Zewail City of Science and Technology, 6 October City, Cairo (Egypt)
2015-10-01
A single field inflation based on a supergravity model with a shift symmetry and U(1) extension of the MSSM is analyzed. We show that one of the real components of the two U(1) charged scalar fields plays the role of inflaton with an effective scalar potential similar to the ''new chaotic inflation'' scenario. Both non-anomalous and anomalous (with Fayet-Iliopoulos term) U(1) are studied. We show that the non-anomalous U(1) scenario is consistent with data of the cosmic microwave background and recent astrophysical measurements. A possible kinetic mixing between U(1) and U(1){sub B−L} is considered in order to allow for natural decay channels of the inflaton, leading to a reheating epoch. Upper limits on the reheating temperature thus turn out to favour an intermediate (∼ O(10{sup 13}) GeV) scale B−L symmetry breaking.
Single field inflation in supergravity with a U(1) gauge symmetry
Energy Technology Data Exchange (ETDEWEB)
Heurtier, L. [Centre de Physique Théorique, École Polytechnique, CNRS,91128 Palaiseau (France); Khalil, S. [Center for Fundamental Physics, Zewail City of Science and Technology,6 October City, Cairo (Egypt); Department of Mathematics, Faculty of Science, Ain Shams University,Cairo, 11566 (Egypt); Moursy, A. [Center for Fundamental Physics, Zewail City of Science and Technology,6 October City, Cairo (Egypt)
2015-10-19
A single field inflation based on a supergravity model with a shift symmetry and U(1) extension of the MSSM is analyzed. We show that one of the real components of the two U(1) charged scalar fields plays the role of inflaton with an effective scalar potential similar to the “new chaotic inflation” scenario. Both non-anomalous and anomalous (with Fayet-Iliopoulos term) U(1) are studied. We show that the non-anomalous U(1) scenario is consistent with data of the cosmic microwave background and recent astrophysical measurements. A possible kinetic mixing between U(1) and U(1){sub B−L} is considered in order to allow for natural decay channels of the inflaton, leading to a reheating epoch. Upper limits on the reheating temperature thus turn out to favour an intermediate (∼O(10{sup 13}) GeV) scale B−L symmetry breaking.
Cvetic, Mirjam; Piragua, Hernan; Taylor, Washington
2015-01-01
We construct the general form of an F-theory compactification with two U(1) factors based on a general elliptically fibered Calabi-Yau manifold with Mordell-Weil group of rank two. This construction produces broad classes of models with diverse matter spectra, including many that are not realized in earlier F-theory constructions with U(1)xU(1) gauge symmetry. Generic U(1)xU(1) models can be related to a Higgsed non-Abelian model with gauge group SU(2)xSU(2)xSU(3), SU(2)^3xSU(3), or a subgroup thereof. The nonlocal horizontal divisors of the Mordell-Weil group are replaced with local vertical divisors associated with the Cartan generators of non-Abelian gauge groups from Kodaira singularities. We give a global resolution of codimension two singularities of the Abelian model; we identify the full anomaly free matter content, and match it to the unHiggsed non-Abelian model. The non-Abelian Weierstrass model exhibits a new algebraic description of the singularities in the fibration that results in the first expl...
Frank, Mariana; Özdal, Özer
2018-01-01
We study the low scale predictions of the supersymmetric standard model extended by U (1 )B -L×U (1 )R symmetry, obtained from S O (10 ) breaking via a left-right supersymmetric model, imposing universal boundary conditions. Two singlet Higgs fields are responsible for the radiative U (1 )B -L×U (1 )R symmetry breaking, and a singlet fermion S is introduced to generate neutrino masses through an inverse seesaw mechanism. The lightest neutralino or sneutrino emerge as dark matter candidates, with different low scale implications. We find that the composition of the neutralino lightest supersymmetric particle (LSP) changes considerably depending on the neutralino LSP mass, from roughly half U (1 )R bino, half minimal supersymmetric model (MSSM) bino, to a singlet higgsino, or completely dominated by the MSSM higgsino. The sneutrino LSP is statistically much less likely, and when it occurs it is a 50-50 mixture of right-handed sneutrino and the scalar S ˜. Most of the solutions consistent with the relic density constraint survive the XENON 1T exclusion curve for both LSP cases. We compare the two scenarios and investigate parameter space points and find consistency with the muon anomalous magnetic moment only at the edge of a 2 σ deviation from the measured value. However, we find that the sneutrino LSP solutions could be ruled out completely by the strict reinforcement of the recent Z' mass bounds. We finally discuss collider prospects for testing the model.
Naturally light neutrinos in the flipped SU(5)xU(1) superstring model
Energy Technology Data Exchange (ETDEWEB)
Antoniadis, I.; Rizos, J. (Centre de Physique Theorique, Ecole Polytechnique, 91 - Palaiseau (France)); Tamvakis, K. (Physics Dept., Univ. Ioannina (Greece))
1992-04-16
We analyze the SU(5)xU(1)'xU(1){sup 4}xSO(10)xSU(4) superstring model, taking into account non-renormalizable superpotential interactions up to sixth order, and find that all neutrinos stay naturally light within the experimental mass bounds. (orig.).
46 CFR 54.01-10 - Steam-generating pressure vessels (modifies U-1(g)).
2010-10-01
... 46 Shipping 2 2010-10-01 2010-10-01 false Steam-generating pressure vessels (modifies U-1(g)). 54... ENGINEERING PRESSURE VESSELS General Requirements § 54.01-10 Steam-generating pressure vessels (modifies U-1(g)). (a) Pressure vessels in which steam is generated are classed as “Unfired Steam Boilers” except as...
A Third-Rank Tensor Field Based on a U(1) Gauge Theory in Loop Space
Shinichi, DEGUCHI; Tadahito, NAKAJIMA; Department of Physics and Atomic Energy Research Institute College of Science and Technology; Department of Physics and Atomic Energy Research Institute College of Science and Technology
1995-01-01
We derive the Stueckelberg formalism extended to a third-rank tensor field from a U(1) gauge theory in loop space, the space of all loops in space-time. The third-rank tensor field is regarded as a constrained U(1) gauge field on the loop space.
Baryon number generation in a flipped SU(5) x U(1) model
International Nuclear Information System (INIS)
Campbell, B.; Hagelin, J.; Nanopoulos, D.V.; Olive, K.A.
1988-01-01
We consider the possibilities for generating a baryon asymmetry in the early universe in a flipped SU(5) x U(1) model inspired by the superstring. Depending on the temperature of the radiation background after inflation we can distinguish between two scenarios for baryogenesis: (1) After reheating the original SU(5) x U(1) symmetry is restored, or there was no inflation at all; (2) reheating after inflation is rather weak and SU(5) x U(1) is broken. In either case the asymmetry is generated by the out-of-equilibrium decays of a massive SU(3) x SU(2) x U(1) singlet field φ m . In the flipped SU(5) x U(1) model, gauge symmetry breaking is triggered by strong coupling phenomena, and is in general accompanied by the production of entropy. We examine constraints on the reheating temperature and the strong coupling scale in each of the scenarios. (orig.)
Closure report for underground storage tank 141-R3U1 and its associated underground piping
Energy Technology Data Exchange (ETDEWEB)
Mallon, B.J.; Blake, R.G.
1994-03-01
Underground storage tank UST 141-R3U1 at Lawrence Livermore National Laboratory (LLNL), was registered with the State Water Resources Control Board on June 27, 1984. This tank system consisted of a concrete tank, lined with polyvinyl chloride, and approximately 100 feet of PVC underground piping. UST 141-R3U1 had a capacity of 450 gallons. The underground piping connected three floor drains and one sink inside Building 141 to UST 141-R3U1. The wastewater collected in UST 141-R3U1 contained organic solvents, metals, and inorganic acids. On November 30, 1987, the 141-R3U1 tank system failed a precision tank test. The 141-R3U1 tank system was subsequently emptied and removed from service pending further precision tests to determine the location of the leak within the tank system. A precision tank test on February 5, 1988, was performed to confirm the November 30, 1987 test. Four additional precision tests were performed on this tank system between February 25, 1988, and March 6, 1988. The leak was located where the inlet piping from Building 141 penetrates the concrete side of UST 141-R3U1. The volume of wastewater that entered the backfill and soil around and/or beneath UST 141-R3U1 is unknown. On December 13, 1989, the LLNL Environmental Restoration Division submitted a plan to close UST 141-R3U1 and its associated piping to the Alameda County Department of Environmental Health. UST 141-R3U1 was closed as an UST, and shall be used instead as additional secondary containment for two aboveground storage tanks.
Closure report for underground storage tank 141-R3U1 and its associated underground piping
International Nuclear Information System (INIS)
Mallon, B.J.; Blake, R.G.
1994-03-01
Underground storage tank UST 141-R3U1 at Lawrence Livermore National Laboratory (LLNL), was registered with the State Water Resources Control Board on June 27, 1984. This tank system consisted of a concrete tank, lined with polyvinyl chloride, and approximately 100 feet of PVC underground piping. UST 141-R3U1 had a capacity of 450 gallons. The underground piping connected three floor drains and one sink inside Building 141 to UST 141-R3U1. The wastewater collected in UST 141-R3U1 contained organic solvents, metals, and inorganic acids. On November 30, 1987, the 141-R3U1 tank system failed a precision tank test. The 141-R3U1 tank system was subsequently emptied and removed from service pending further precision tests to determine the location of the leak within the tank system. A precision tank test on February 5, 1988, was performed to confirm the November 30, 1987 test. Four additional precision tests were performed on this tank system between February 25, 1988, and March 6, 1988. The leak was located where the inlet piping from Building 141 penetrates the concrete side of UST 141-R3U1. The volume of wastewater that entered the backfill and soil around and/or beneath UST 141-R3U1 is unknown. On December 13, 1989, the LLNL Environmental Restoration Division submitted a plan to close UST 141-R3U1 and its associated piping to the Alameda County Department of Environmental Health. UST 141-R3U1 was closed as an UST, and shall be used instead as additional secondary containment for two aboveground storage tanks
U1 snDNA clusters in grasshoppers: chromosomal dynamics and genomic organization
Anjos, A; Ruiz-Ruano, F J; Camacho, J P M; Loreto, V; Cabrero, J; de Souza, M J; Cabral-de-Mello, D C
2015-01-01
The spliceosome, constituted by a protein set associated with small nuclear RNA (snRNA), is responsible for mRNA maturation through intron removal. Among snRNA genes, U1 is generally a conserved repetitive sequence. To unveil the chromosomal/genomic dynamics of this multigene family in grasshoppers, we mapped U1 genes by fluorescence in situ hybridization in 70 species belonging to the families Proscopiidae, Pyrgomorphidae, Ommexechidae, Romaleidae and Acrididae. Evident clusters were observed in all species, indicating that, at least, some U1 repeats are tandemly arrayed. High conservation was observed in the first four families, with most species carrying a single U1 cluster, frequently located in the third or fourth longest autosome. By contrast, extensive variation was observed among Acrididae, from a single chromosome pair carrying U1 to all chromosome pairs carrying it, with occasional occurrence of two or more clusters in the same chromosome. DNA sequence analysis in Eyprepocnemis plorans (species carrying U1 clusters on seven different chromosome pairs) and Locusta migratoria (carrying U1 in a single chromosome pair) supported the coexistence of functional and pseudogenic lineages. One of these pseudogenic lineages was truncated in the same nucleotide position in both species, suggesting that it was present in a common ancestor to both species. At least in E. plorans, this U1 snDNA pseudogenic lineage was associated with 5S rDNA and short interspersed elements (SINE)-like mobile elements. Given that we conclude in grasshoppers that the U1 snDNA had evolved under the birth-and-death model and that its intragenomic spread might be related with mobile elements. PMID:25248465
Matrix models from localization of five-dimensional supersymmetric noncommutative U(1) gauge theory
International Nuclear Information System (INIS)
Lee, Bum-Hoon; Ro, Daeho; Yang, Hyun Seok
2017-01-01
We study localization of five-dimensional supersymmetric U(1) gauge theory on S 3 ×ℝ θ 2 where ℝ θ 2 is a noncommutative (NC) plane. The theory can be isomorphically mapped to three-dimensional supersymmetric U(N→∞) gauge theory on S 3 using the matrix representation on a separable Hilbert space on which NC fields linearly act. Therefore the NC space ℝ θ 2 allows for a flexible path to derive matrix models via localization from a higher-dimensional supersymmetric NC U(1) gauge theory. The result shows a rich duality between NC U(1) gauge theories and large N matrix models in various dimensions.
F-theory and all things rational: surveying U(1) symmetries with rational sections
International Nuclear Information System (INIS)
Lawrie, Craig; Schäfer-Nameki, Sakura; Wong, Jin-Mann
2015-01-01
We study elliptic fibrations for F-theory compactifications realizing 4d and 6d supersymmetric gauge theories with abelian gauge factors. In the fibration these U(1) symmetries are realized in terms of additional rational section. We obtain a universal characterization of all the possible U(1) charges of matter fields by determining the corresponding codimension two fibers with rational sections. In view of modelling supersymmetric Grand Unified Theories, one of the main examples that we analyze are U(1) symmetries for SU(5) gauge theories with 5̄ and 10 matter. We use a combination of constraints on the normal bundle of rational curves in Calabi-Yau three- and four-folds, as well as the splitting of rational curves in the fibers in codimension two, to determine the possible configurations of smooth rational sections. This analysis straightforwardly generalizes to multiple U(1)s. We study the flops of such fibers, as well as some of the Yukawa couplings in codimension three. Furthermore, we carry out a universal study of the U(1)-charged GUT singlets, including their KK-charges, and determine all realizations of singlet fibers. By giving vacuum expectation values to these singlets, we propose a systematic way to analyze the Higgsing of U(1)s to discrete gauge symmetries in F-theory.
Nonminimal quartic inflation in classically conformal U(1 ) X extended standard model
Oda, Satsuki; Okada, Nobuchika; Raut, Digesh; Takahashi, Dai-suke
2018-03-01
We propose quartic inflation with nonminimal gravitational coupling in the context of the classically conformal U(1 ) X extension of the standard model (SM). In this model, the U(1 ) X gauge symmetry is radiatively broken through the Coleman-Weinberg mechanism, by which the U(1 ) X gauge boson (Z' boson) and the right-handed Majorana neutrinos acquire their masses. We consider their masses in the range of O (10 GeV )-O (10 TeV ) , which are accessible to high-energy collider experiments. The radiative U(1 ) X gauge symmetry breaking also generates a negative mass squared for the SM Higgs doublet, and the electroweak symmetry breaking occurs subsequently. We identify the U(1 ) X Higgs field with inflaton and calculate the inflationary predictions. Because of the Coleman-Weinberg mechanism, the inflaton quartic coupling during inflation, which determines the inflationary predictions, is correlated to the U(1 ) X gauge coupling. With this correlation, we investigate complementarities between the inflationary predictions and the current constraint from the Z' boson resonance search at the LHC Run 2 as well as the prospect of the search for the Z' boson and the right-handed neutrinos at the future collider experiments.
Tuned and non-Higgsable U(1)s in F-theory
Energy Technology Data Exchange (ETDEWEB)
Wang, Yi-Nan [Center for Theoretical Physics, Department of Physics, Massachusetts Institute of Technology,77 Massachusetts Avenue, Cambridge, MA 02139 (United States)
2017-03-27
We study the tuning of U(1) gauge fields in F-theory models on a base of general dimension. We construct a formula that computes the change in Weierstrass moduli when such a U(1) is tuned, based on the Morrison-Park form of a Weierstrass model with an additional rational section. Using this formula, we propose the form of “minimal tuning” on any base, which corresponds to the case where the decrease in the number of Weierstrass moduli is minimal. Applying this result, we discover some universal features of bases with non-Higgsable U(1)s. Mathematically, a generic elliptic fibration over such a base has additional rational sections. Physically, this condition implies the existence of U(1) gauge group in the low-energy supergravity theory after compactification that cannot be Higgsed away. In particular, we show that the elliptic Calabi-Yau manifold over such a base has a small number of complex structure moduli. We also suggest that non-Higgsable U(1)s can never appear on any toric bases. Finally, we construct the first example of a threefold base with non-Higgsable U(1)s.
U1 snRNP Alteration and Neuronal Cell Cycle Reentry in Alzheimer Disease
Directory of Open Access Journals (Sweden)
Bing Bai
2018-03-01
Full Text Available The aberrancy of U1 small nuclear ribonucleoprotein (snRNP complex and RNA splicing has been demonstrated in Alzheimer’s disease (AD. Importantly, the U1 proteopathy is AD-specific, widespread and early-occurring, thus providing a very unique clue to the AD pathogenesis. The prominent feature of U1 histopathology is its nuclear depletion and redistribution in the neuronal cytoplasm. According to the preliminary data, the initial U1 cytoplasmic distribution pattern is similar to the subcellular translocation of the spliceosome in cells undergoing mitosis. This implies that the U1 mislocalization might reflect the neuronal cell cycle-reentry (CCR which has been extensively evidenced in AD brains. The CCR phenomenon explains the major molecular and cellular events in AD brains, such as Tau and amyloid precursor protein (APP phosphorylation, and the possible neuronal death through mitotic catastrophe (MC. Furthermore, the CCR might be mechanistically linked to inflammation, a critical factor in the AD etiology according to the genetic evidence. Therefore, the discovery of U1 aberrancy might strengthen the involvement of CCR in the AD neuronal degeneration.
International Nuclear Information System (INIS)
Yamamoto, Hisashi.
1993-07-01
We study the long-distance relevance of vortices (instantons) in an N-component axially U(1)-gauged four-Fermi theory in 1 + 1 dimensions, in which a naive use of 1/N expansion predicts the dynamical Higgs phenomenon. Its general effective lagrangian is found to be a frozen U(1) Higgs model with the gauge-field mass term proportional to an anomaly parameter (b). The dual-transformed versions of the effective theory are represented by sine-Gordon systems and recursion-relation analyses are performed. The results suggest that in the gauge-invariant scheme (b = 0) vortices are always relevant at long distances, while in non-invariant schemes (b > 0) there exists a critical N above which the long-distance behavior is dominated by a free massless scalar field. (author)
SU(3)_C× SU(2)_L× U(1)_Y( × U(1)_X ) as a symmetry of division algebraic ladder operators
Furey, C.
2018-05-01
We demonstrate a model which captures certain attractive features of SU(5) theory, while providing a possible escape from proton decay. In this paper we show how ladder operators arise from the division algebras R, C, H, and O. From the SU( n) symmetry of these ladder operators, we then demonstrate a model which has much structural similarity to Georgi and Glashow's SU(5) grand unified theory. However, in this case, the transitions leading to proton decay are expected to be blocked, given that they coincide with presumably forbidden transformations which would incorrectly mix distinct algebraic actions. As a result, we find that we are left with G_{sm} = SU(3)_C× SU(2)_L× U(1)_Y / Z_6. Finally, we point out that if U( n) ladder symmetries are used in place of SU( n), it may then be possible to find this same G_{sm}=SU(3)_C× SU(2)_L× U(1)_Y / Z_6, together with an extra U(1)_X symmetry, related to B-L.
Coenzyme O*U1*UO, Alpha-Tocopherol and Free Cholesterol in HDL and LDL Fractions
DEFF Research Database (Denmark)
Johansen, Kurt; Theorell, Henning; Karlsson, Jan
1991-01-01
Farmakologi, Alpha-tocopherol, Coenzyme Q*U1*U0, free cholesterol, LDL, Antioxidants, Lipoproteins, HDL......Farmakologi, Alpha-tocopherol, Coenzyme Q*U1*U0, free cholesterol, LDL, Antioxidants, Lipoproteins, HDL...
Gravity/Fluid Correspondence and Its Application on Bulk Gravity with U(1) Gauge Field
International Nuclear Information System (INIS)
Hu, Ya-Peng; Zhang, Jian-Hui
2014-01-01
As the long wavelength limit of the AdS/CFT correspondence, the gravity/fluid correspondence has been shown to be a useful tool for extracting properties of the fluid on the boundary dual to the gravity in the bulk. In this paper, after briefly reviewing the algorithm of gravity/fluid correspondence, we discuss the results of its application on bulk gravity with a U(1) gauge field. In the presence of a U(1) gauge field, the dual fluid possesses more interesting properties such as its charge current. Furthermore, an external field A_μ"e"x"t could affect the charge current, and the U(1) Chern-Simons term also induces extra structures to the dual current giving anomalous transport coefficients.
QCD sum rules for the gluon component of the U(1)sub(A) pseudoscalar meson
International Nuclear Information System (INIS)
Narison, S.; Centre National de la Recherche Scientifique, 13 - Marseille
1981-01-01
Using sum rules based on the positivity and the analyticity of the U(1)sub(A) spectral functions, and within the framework of QCD (quantum chromodynamics), we derive an upper bound Msub(p) approximately less than (0.6 approximately 0.75) GeV to the gluon component of the U(1)sub(A) meson mass. Such a bound could be identified as the exact value of Msub(p) if one accepts a QCD model for the ''continuum'' contribution to the U(1)sub(A) spectral functions. Comparing our result to the observed mass Msub(eta)' approximately equal to 0.96GeV, one could expect an important gluonic contribution to the eta'-mass. This experimental result could be reproduced, if one adds to our result, the quark contribution known to be Msub(q) approximately equal to root(3)msub(π). (author)
Oscillating asymmetric sneutrino dark matter from the maximally U(1L supersymmetric inverse seesaw
Directory of Open Access Journals (Sweden)
Shao-Long Chen
2016-10-01
Full Text Available The inverse seesaw mechanism provides an attractive approach to generate small neutrino mass, which origins from a tiny U(1L breaking. In this paper, we work in the supersymmetric version of this mechanism, where the singlet-like sneutrino could be an asymmetric dark matter (ADM candidate in the maximally U(1L symmetric limit. However, even a tiny δm, the mass splitting between sneutrino and anti-sneutrino as a result of the tiny U(1L breaking effect, could lead to fast oscillation between sneutrino and anti-sneutrino and thus spoils the ADM scenario. We study the evolution of this oscillation and find that a weak scale sneutrino, which tolerates a relatively larger δm∼10−5 eV, is strongly favored. We also investigate possible natural ways to realize that small δm in the model.
Renormalization group aspects of 3-dimensional Pure U(1) lattice gauge theory
International Nuclear Information System (INIS)
Gopfert, M.; Mack, G.
1983-01-01
A few surprises in a recent study of the 3-dimensional pure U(1) lattice gauge theory model, from the point of view of the renormalization group theory, are discussed. Since the gauge group U(1) of this model is abelian, the model is subject to KramersWannier duality transformation. One obtains a ferromagnet with a global symmetry group Z. The duality transformation shows that the surface tension alpha of the model equals the strong tension of the U(1) gauge model. A theorem to represent the true asymptotic behaviour of alpha is derived. A second theorem considers the correlation functions. Discrepiancies between the theorems result in a solution that ''is regarded as a catastrophe'' in renormalization group theory. A lesson is drawn: To choose a good block spin in a renormalization group procedure, know what the low lying excitations of the theory are, to avoid integrating some of them by mischief
F-theory GUTs with U(1) symmetries: Generalities and survey
International Nuclear Information System (INIS)
Dolan, Matthew J.; Marsano, Joseph; Saulina, Natalia; Schaefer-Nameki, Sakura
2011-01-01
We study the structure of SU(5) F-theory grand unified theory (GUT) models that engineer additional U(1) symmetries. These are highly constrained by a set of relations observed by Dudas and Palti (DP) that originate from the physics of four-dimensional anomaly cancellation. Using the DP relations, we describe a general tension between unification and the suppression of dimension 5 proton decay when one or more U(1)'s are Peccei-Quinn (PQ) symmetries and hypercharge flux is used to break the SU(5) GUT group. We then specialize to spectral cover models, whose global completions in F theory we know how to construct. In that setting, we provide a technical derivation of the DP relations, construct spectral covers that yield all possible solutions to them, and provide a complete survey of spectral cover models for SU(5) GUTs that exhibit two U(1) symmetries.
Scalar dark matter interpretation of the DAMPE data with U(1) gauge interactions
Cao, Junjie; Feng, Lei; Guo, Xiaofei; Shang, Liangliang; Wang, Fei; Wu, Peiwen
2018-05-01
Recently, the Dark Matter Particle Explorer (DAMPE) experiment released the new measurement of the total cosmic e+e- flux between 25 GeV and 4.6 TeV, which indicates a spectral softening at around 0.9 TeV and a tentative peak at around 1.4 TeV. We utilize a scalar dark matter (DM) model to explain the DAMPE peak by χ χ →Z'Z'→ℓℓ ¯ ℓ'ℓ' ¯ with an additional anomaly-free gauged U (1 ) family symmetry, in which χ , Z', and ℓ(') denote, respectively, the scalar DM, the new gauge boson, and ℓ(')=e , μ , τ with mχ˜mZ'˜2 ×1.5 (TeV ) . We first illustrate that the minimal framework GSM×U (1 )Y' with the above mass choices can explain the DAMPE excess, which, however, be excluded by LHC constraints from the Z' searches. Then, we study a nonminimal framework GSM×U (1 )Y'×U (1 )Y'' in which U (1 )Y'' mixes with U (1)Y'. We show that such a framework can interpret the DAMPE data and at the same time survive all other constraints including the DM relic abundance, DM direct detection, and collider bounds. We also investigate the predicted e+e- spectrum in this framework and find that the mass splitting Δ m =mχ-mZ'' should be less than about 17 GeV to produce the peaklike structure.
Some comments on flipped SU(5) times U(1) and flipped unification in general
Energy Technology Data Exchange (ETDEWEB)
Barr, S.M. (Bartol Research Institute, University of Delaware, Newark, Delaware 19716 (US))
1989-10-01
A general group-theoretical discussion of flipped embeddings is given. In addition to the well-known flipped SU(5) and flipped SO(10), the existence of flipped E{sub 6} and E{sub 7} is shown, as well as several families and special cases of flipped embeddings. A possible physical reason, essentially based on the group theory of flipped embeddings, why nature prefers the low-energy group SU(3){times}SU(2){times}U(1) to alternatives such as SU(4){times}U(1) and SU(5) is pointed out.
Some comments on flipped SU(5)xU(1) and flipped unification in general
International Nuclear Information System (INIS)
Barr, S.M.
1989-01-01
A general group-theoretical discussion of flipped embeddings is given. In addition to the well-known flipped SU(5) and flipped SO(10), the existence of flipped E 6 and E 7 is shown, as well as several families and special cases of flipped embeddings. A possible physical reason, essentially based on the group theory of flipped embeddings, why nature prefers the low-energy group SU(3)xSU(2)xU(1) to alternatives such as SU(4)xU(1) and SU(5) is pointed out
Remarks on mass and angular momenta for U(1){sup 2}-invariant initial data
Energy Technology Data Exchange (ETDEWEB)
Alaee, Aghil, E-mail: aak818@mun.ca; Kunduri, Hari K., E-mail: hkkunduri@mun.ca [Department of Mathematics and Statistics, Memorial University of Newfoundland, St John’s, Newfoundland and Labrador NL A1C 4P5 (Canada)
2016-03-15
We extend Brill’s positive mass theorem to a large class of asymptotically flat, maximal, U(1){sup 2}-invariant initial data sets on simply connected four dimensional manifolds Σ. Moreover, we extend the local mass angular momenta inequality result [A. Alaee and H. K. Kunduri, Classical Quantum Gravity 32(16), 165020 (2015)] for U(1){sup 2} invariant black holes to the case with nonzero stress energy tensor with positive matter density and energy-momentum current invariant under the above symmetries.
Duality invariance of non-anticommutative N = 1/2 supersymmetric U(1) gauge theory
International Nuclear Information System (INIS)
Dayi, Oemer F.; Kelleyane, Lara T.; Uelker, Kayhan
2005-01-01
A parent action is introduced to formulate (S-) dual of non-anticommutative N = 1/2 supersymmetric U(1) gauge theory. Partition function for parent action in phase space is utilized to establish the equivalence of partition functions of the theories which this parent action produces. Thus, duality invariance of non-anticommutative N = 1/2 supersymmetric U(1) gauge theory follows. The results which we obtained are valid at tree level or equivalently at the first order in the nonanticommutativity parameter C μν
Dark Gauge U(1) symmetry for an alternative left-right model
Kownacki, Corey; Ma, Ernest; Pollard, Nicholas; Popov, Oleg; Zakeri, Mohammadreza
2018-02-01
An alternative left-right model of quarks and leptons, where the SU(2)_R lepton doublet (ν ,l)_R is replaced with (n,l)_R so that n_R is not the Dirac mass partner of ν _L, has been known since 1987. Previous versions assumed a global U(1)_S symmetry to allow n to be identified as a dark-matter fermion. We propose here a gauge extension by the addition of extra fermions to render the model free of gauge anomalies, and just one singlet scalar to break U(1)_S. This results in two layers of dark matter, one hidden behind the other.
Camargo-Molina, José Eliel; Mandal, Tanumoy; Pasechnik, Roman; Wessén, Jonas
2018-03-01
We describe a class of three Higgs doublet models (3HDMs) with a softly broken U(1) × U(1) family symmetry that enforces a Cabibbo-like quark mixing while forbidding tree-level flavour changing neutral currents. The hierarchy in the observed quark masses is partly explained by a softer hierarchy in the vacuum expectation values of the three Higgs doublets. As a consequence, the physical scalar spectrum contains a Standard Model (SM) like Higgs boson h 125 while exotic scalars couple the strongest to the second quark family, leading to rather unconventional discovery channels that could be probed at the Large Hadron Collider. In particular, we describe a search strategy for the lightest charged Higgs boson H ±, through the process c\\overline{s}\\to {H}+\\to {W}+{h}_{125} , using a multivariate analysis that leads to an excellent discriminatory power against the SM background. Although the analysis is applied to the proposed class of 3HDMs, we employ a model-independent formulation such that it can be applied to any other model with the same discovery channel.
Irges, Nikos; Zoupanos, George
2011-01-01
We present an extension of the Standard Model inspired by the E_8 x E_8 Heterotic String. In order that a reasonable effective Lagrangian is presented we neglect everything else other than the ten-dimensional N=1 supersymmetric Yang-Mills sector associated with one of the gauge factors and certain couplings necessary for anomaly cancellation. We consider a compactified space-time M_4 x B_0 / Z_3, where B_0 is the nearly-Kaehler manifold SU(3)/U(1) x U(1) and Z_3 is a freely acting discrete group on B_0. Then we reduce dimensionally the E_8 on this manifold and we employ the Wilson flux mechanism leading in four dimensions to an SU(3)^3 gauge theory with the spectrum of a N=1 supersymmetric theory. We compute the effective four-dimensional Lagrangian and demonstrate that an extension of the Standard Model is obtained with interesting features including a conserved baryon number and fixed tree level Yukawa couplings and scalar potential. The spectrum contains new states such as right handed neutrinos and heavy ...
q-deformation of ''W3'', Virasoro and U(1)-Kac-Moody algebras
International Nuclear Information System (INIS)
El Hassouni, A.; Tahri, E.H.; Zakkari, M.
1995-07-01
A deformation of the algebra of infinite matrices gl(∞, C) is given. We show that this operation leads to the realization of a deformed ''W 3 '' like algebra. The central extension of the q-U(1) Kac-Moody and the q-Virasoro algebra is performed. (author). 10 refs
The 17 MeV anomaly in beryllium decays and U(1) portal to dark matter
Chen, Chian-Shu; Lin, Guey-Lin; Lin, Yen-Hsun; Xu, Fanrong
2017-11-01
The experiment of Krasznahorkay et al. observed the transition of a 8Be excited state to its ground state and accompanied by an emission of an e+e‑ pair with 17 MeV invariant mass. This 6.8σ anomaly can be fitted by a new light gauge boson. We consider the new particle as a U(1) gauge boson, Z‧, which plays as a portal linking dark sector and visible sector. In particular, we study the new U(1) gauge symmetry as a hidden or nonhidden group separately. The generic hidden U(1) model, referred to as dark Z model, is excluded by imposing various experimental constraints. On the other hand, a nonhidden Z‧ is allowed due to the additional interactions between Z‧ and Standard Model fermions. We also study the implication of the dark matter direct search on such a scenario. We found that the search for the DM-nucleon scattering cannot probe the parameter space that is allowed by 8Be-anomaly for the range of DM mass above 500 MeV. However, the DM-electron scattering for DM between 20 MeV and 50 MeV can test the underlying U(1) portal model using the future Si and Ge detectors with the 5e‑ threshold charges.
New fermion mass textures from anomalous U(1) symmetries with baryon and lepton number conservation
Leontaris, George K
2000-01-01
In this paper, we present solutions to the fermion mass hierarchy problem in the context of the minimal supersymmetric standard theory augmented by an anomalous family-dependent U(1)_X symmetry. The latter is spontaneously broken by non-zero vevs of a pair of singlet fields whose magnitude is determined through the D- and F-flatness conditions of the superpotential. We derive the general solutions to the anomaly cancellation conditions and show that they allow numerous choices for the U(1)_X fermion charges which give several fermion mass textures in agreement with the observed fermion mass hierarchy and mixing. Solutions with U(1)_X fermion charge assignments are found which forbid or substantially suppress the dangerous baryon and lepton number violating operators and the lepton-higgs mixing coupling while a higgs mixing mass classification of the fermion mass textures with respect to the sum of the doublet-higgs U(1)_X-charges and show that suppression of dimension-five operators naturally occurs for vario...
Right-handed neutrino dark matter in a U(1) extension of the Standard Model
Cox, Peter; Han, Chengcheng; Yanagida, Tsutomu T.
2018-01-01
We consider minimal U(1) extensions of the Standard Model in which one of the right-handed neutrinos is charged under the new gauge symmetry and plays the role of dark matter. In particular, we perform a detailed phenomenological study for the case of a U(1)(B‑L)3 flavoured B‑L symmetry. If perturbativity is required up to high-scales, we find an upper bound on the dark matter mass of mχlesssim2 TeV, significantly stronger than that obtained in simplified models. Furthermore, if the U(1)(B‑L)3 breaking scalar has significant mixing with the SM Higgs, there are already strong constraints from direct detection. On the other hand, there remains significant viable parameter space in the case of small mixing, which may be probed in the future via LHC Z' searches and indirect detection. We also comment on more general anomaly-free symmetries consistent with a TeV-scale RH neutrino dark matter candidate, and show that if two heavy RH neutrinos for leptogenesis are also required, one is naturally led to a single-parameter class of U(1) symmetries.
Electromagnetic mass differences in the SU(3) x U(1) gauge model
International Nuclear Information System (INIS)
Maharana, K.; Sastry, C.V.
1975-01-01
In this note we point out that the electromagnetic mass differences of the pion and kaon in the SU(3) times U(1) model are the same as in Weinberg's model except for the differences in the masses of the gauge bosons
Higher-spin cluster algorithms: the Heisenberg spin and U(1) quantum link models
Energy Technology Data Exchange (ETDEWEB)
Chudnovsky, V
2000-03-01
I discuss here how the highly-efficient spin-1/2 cluster algorithm for the Heisenberg antiferromagnet may be extended to higher-dimensional representations; some numerical results are provided. The same extensions can be used for the U(1) flux cluster algorithm, but have not yielded signals of the desired Coulomb phase of the system.
Higher-spin cluster algorithms: the Heisenberg spin and U(1) quantum link models
International Nuclear Information System (INIS)
Chudnovsky, V.
2000-01-01
I discuss here how the highly-efficient spin-1/2 cluster algorithm for the Heisenberg antiferromagnet may be extended to higher-dimensional representations; some numerical results are provided. The same extensions can be used for the U(1) flux cluster algorithm, but have not yielded signals of the desired Coulomb phase of the system
Deep-inelastic lepton scattering in an SU(3) x U(1) gauge model
International Nuclear Information System (INIS)
Maharana, K.; Sastry, C.V.
1976-01-01
Linear relations and sum rules for deep-inelastic lepton scattering are derived in the light-cone algebra approach from a set of weak, neutral, and electromagnetic currents based on an SU(3) x U(1) gauge model proposed by Schechter and Ueda
SU(5) x U(1) phenomenology: Theorems on neutral-current analysis
International Nuclear Information System (INIS)
Zee, A.; Kim, J.E.
1980-01-01
We embed the SU(5) unified theory of Georgi and Glashow in a U(5) theory. This may result from the breaking of an SU(N), N>5, theory or of a GL(5,c) theory. At low energy this leads to an SU(2) x U(1) x U(1) electroweak theory. We show that, with a suitable choice of Higgs representations, the predictions of this theory for neutral-current experiments are characterized by three parameters. For appropriate values of these parameters, the predictions are practically indistinguishable from the standard SU(2) x U(1) theory. Certain theorems on the analysis of neutral-current interactions are proved. (Section V is independent for readers who are interested only in the theorems.) More accurate neutral-current measurement might answer the question of whether SU(5) x U(1) is relevant. Possible verification of the present electroweak theory can result from (roughly) an order suppression relative to the standard prediction on the asymmetries in e + e - → μ + μ - and discovery of two Z bosons around 90 --100 GeV. GL(n,c) gauge theories are formulated in the Appendix
Asymptotic behaviour in polarized and half-polarized U(1) symmetric vacuum spacetimes
International Nuclear Information System (INIS)
Isenberg, James; Moncrief, Vincent
2002-01-01
We use the Fuchsian algorithm to study the behaviour near the singularity of certain families of U(1) symmetric solutions of the vacuum Einstein equations (with the U(1) isometry group acting spatially). We consider an analytic family of polarized solutions with the maximum number of arbitrary functions consistent with the polarization condition (one of the 'gravitational degrees of freedom' is turned off) and show that all members of this family are asymptotically velocity term dominated (AVTD) as one approaches the singularity. We show that the same AVTD behaviour holds for a family of 'half-polarized' solutions, which is defined by adding one extra arbitrary function to those characterizing the polarized solutions. (The full set of nonpolarized solutions involves two extra arbitrary functions.) Using SL(2, R) Geroch transformations, we produce a further class of U(1) symmetric solutions with AVTD behaviour. We begin to address the issue of whether AVTD behaviour is independent of the choice of time foliation by showing that indeed AVTD behaviour is seen for a wide class of choices of harmonic time in the polarized and half-polarized (U(1) symmetric vacuum) solutions discussed here
Duality in the U(1) Higgs model with an external field
International Nuclear Information System (INIS)
Damgaard, P.H.
1988-07-01
An external electromagnetic field is coupled to the lattice U(1) Higgs model in a Villain form. Duality transformations are then used to express the partition function in terms of an effective Lagrangian of topological excitations and their couplings to the external field. Consequences for the phase diagram are derived. (orig.)
Quark seesaw mechanism, dark U (1 ) symmetry, and the baryon-dark matter coincidence
Gu, Pei-Hong; Mohapatra, Rabindra N.
2017-09-01
We attempt to understand the baryon-dark matter coincidence problem within the quark seesaw extension of the standard model where parity invariance is used to solve the strong C P problem. The S U (2 )L×S U (2 )R×U (1 )B -L gauge symmetry of this model is extended by a dark U (1 )X group plus inclusion of a heavy neutral vector-like fermion χL ,R charged under the dark group which plays the role of dark matter. All fermions are Dirac type in this model. Decay of heavy scalars charged under U (1 )X leads to simultaneous asymmetry generation of the dark matter and baryons after sphaleron effects are included. The U (1 )X group not only helps to stabilize the dark matter but also helps in the elimination of the symmetric part of the dark matter via χ -χ ¯ annihilation. For dark matter mass near the proton mass, it explains why the baryon and dark matter abundances are of similar magnitude (the baryon-dark matter coincidence problem). This model is testable in low threshold (sub-keV) direct dark matter search experiments.
The flipped SU(5)xU(1) string model revamped
Energy Technology Data Exchange (ETDEWEB)
Antoniadis, I.; Ellis, J.; Hagelin, J.S.; Nanopoulos, D.V. (European Organization for Nuclear Research, Geneva (Switzerland))
1989-11-02
We present a refined version of our three-generation flipped SU(5)xU(1) string model with the following properties. The complete massless spectrum is derived and shown to be free of all gauge and mixed anomalies apart from a single anomalous U(1). The imaginary part of the dilaton supermultiplet is eaten by the anomalous U(1) gauge boson, and the corresponding D-term is cancelled by large VEVs for singlet fields that break surplus U(1) gauge factors, leaving a supersymmetric vacuum with an SU(5)xU(1) visible gauge group and an SO(10)xSO(6) hidden gauge group. There are sufficient Higgs multiplets to break the visible gauge symmetry down to the standard model in an essentially unique way. All trilinear superpotential couplings have been calculated and there are in particular some giving m{sub t}, m{sub b}, m{sub tau}ne0. A renormalization group analysis shows that m{sub t}<190 GeV and m{sub b}{approx equal}3m{sub tau}. Light Higgs doublets are split automatically from heavy Higgs triplets, leaving no residual dimension-five operators for baryon decay, and the baryon lifetime tau{sub B} {approx equal} 2x10{sup 34{plus minus}2} yr. There are no tree-level flavour-changing neutral currents, but muyieldsegamma may occur at a detectable level: B(muyieldsegamma){proportional to} 10{sup -11}-10{sup -14}. (orig.).
Flipped SU(5)xU(1){sub X} models from F-theory
Energy Technology Data Exchange (ETDEWEB)
Jiang Jing [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Li Tianjun, E-mail: tjli@physics.rutgers.ed [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States); Key Laboratory of Frontiers in Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190 (China); Nanopoulos, Dimitri V. [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States); Astroparticle Physics Group, Houston Advanced Research Center (HARC), Mitchell Campus, Woodlands, TX 77381 (United States); Academy of Athens, Division of Natural Sciences, 28 Panepistimiou Avenue, Athens 10679 (Greece); Xie Dan [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States)
2010-05-01
We systematically construct flipped SU(5)xU(1){sub X} models without and with bulk vector-like particles from F-theory. To realize the decoupling scenario, we introduce sets of vector-like particles in complete SU(5)xU(1) multiplets at the TeV scale, or at the intermediate scale, or at the TeV scale and high scale. To avoid the Landau pole problem for the gauge couplings, we can only introduce five sets of vector-like particles around the TeV scale. These vector-like particles can couple to the Standard Model singlet fields, and obtain suitable masses by Higgs mechanism. We study gauge coupling unification in detail. We show that the U(1){sub X} flux contributions to the gauge couplings preserve the SU(5)xU(1){sub X} gauge coupling unification. We calculate the SU(3){sub C}xSU(2){sub L} unification scales, and the SU(5)xU(1){sub X} unification scales and unified couplings. In most of our models, the high-scale or bulk vector-like particles can be considered as string-scale threshold corrections since their masses are close to the string scale. Furthermore, we discuss the phenomenological consequences of our models. In particular, in the models with TeV-scale vector-like particles, the vector-like particles can be observed at the Large Hadron Collider, the proton decay is within the reach of the future Hyper-Kamiokande experiment, the lightest CP-even Higgs boson mass can be increased, the hybrid inflation can be naturally realized, and the correct cosmic primordial density fluctuations can be generated.
Higgs phenomenology in the minimal S U (3 )L×U (1 )X model
Okada, Hiroshi; Okada, Nobuchika; Orikasa, Yuta; Yagyu, Kei
2016-07-01
We investigate the phenomenology of a model based on the S U (3 )c×S U (3 )L×U (1 )X gauge theory, the so-called 331 model. In particular, we focus on the Higgs sector of the model which is composed of three S U (3 )L triplet Higgs fields and is the minimal form for realizing a phenomenologically acceptable scenario. After the spontaneous symmetry breaking S U (3 )L×U (1 )X→S U (2 )L×U (1 )Y , our Higgs sector effectively becomes that with two S U (2 )L doublet scalar fields, in which the first- and the second-generation quarks couple to a different Higgs doublet from that which couples to the third-generation quarks. This structure causes the flavor-changing neutral current mediated by Higgs bosons at the tree level. By taking an alignment limit of the mass matrix for the C P -even Higgs bosons, which is naturally realized in the case with the breaking scale of S U (3 )L×U (1 )X much larger than that of S U (2 )L×U (1 )Y, we can avoid current constraints from flavor experiments such as the B0-B¯ 0 mixing even for the Higgs bosons masses that are O (100 ) GeV . In this allowed parameter space, we clarify that a characteristic deviation in quark Yukawa couplings of the Standard Model-like Higgs boson is predicted, which has a different pattern from that seen in two Higgs doublet models with a softly broken Z2 symmetry. We also find that the flavor-violating decay modes of the extra Higgs boson, e.g., H /A →t c and H±→t s , can be dominant, and they yield the important signature to distinguish our model from the two Higgs doublet models.
Retracing the phenomenology of the flipped SU(5)xU(1) superstring model
Energy Technology Data Exchange (ETDEWEB)
Rizos, J.; Tamvakis, K. (Ioannina Univ. (Greece). Dept. of Physics)
1990-11-22
We study in detail gauge symmetry breaking in the SU(5)xU(1)'xU(1){sup 4}xSO(10)xSO(6) superstring model, solving the D- and F-flatness conditions and taking into account quartic and quintic superpotential terms. We find that, to this order, the model describes two massive generations of quarks and leptons as well as a massless generation expected to receive naturally suppressed masses from higher order non-renormalizable terms. We show that D-flatness restricts the number of massless isodoublets to four. We also extract an inequality relating the top quark mass to M{sub W}. (orig.).
Neutrino masses from U(1) symmetries and the Super-Kamiokande data
Lola, S; Lola, Smaragda; Ross, Graham G.
1999-01-01
Motivated by the Super-Kamiokande data, we revisit models with U(1) symmetries and discuss the origin of neutrino masses and mixings in such theories. We show that, in models with just three light neutrinos and a hierarchy of neutrino masses, large (2-3) mixing fixes the lepton doublet U(1) charges and is thus related to the structure of the charged lepton mass matrix. We discuss the fermion mass structure that follows from the abelian family symmetry with an extended gauge group. Requiring that the quark and lepton masses be ordered by the family symmetry, we identify the most promising scheme. This requires large, but not necessarily maximal, mixing in the mu tau sector and gives e mu mixing in the range that is required for the small angle solution of the solar neutrino deficit.
Geometrical origin of tricritical points of various U(1) lattice models
International Nuclear Information System (INIS)
Janke, W.; Kleiert, H.
1989-01-01
The authors review the dual relationship between various compact U(1) lattice models and Abelian Higgs models, the latter being the disorder field theories of line-like topological excitations in the system. The authors point out that the predicted first-order transitions in the Abelian Higgs models (Coleman-Weinberg mechanism) are, in three dimensions, in contradiction with direct numerical investigations in the compact U(1) formulation since these yield continuous transitions in the major part of the phase diagram. In four dimensions, there are indications from Monte Carlo data for a similar situation. Concentrating on the strong-coupling expansion in terms of geometrical objects, surfaces or lines, with certain statistical weights, the authors present semi-quantitative arguments explaining the observed cross-over from first-order to continuous transitions by the balance between the lowest two weights (2:1 ratio) of these geometrical objects
Diphoton excess from hidden U(1 gauge symmetry with large kinetic mixing
Directory of Open Access Journals (Sweden)
Fuminobu Takahashi
2016-09-01
Full Text Available We show that the 750 GeV diphoton excess can be explained by introducing vector-like quarks and hidden fermions charged under a hidden U(1 gauge symmetry, which has a relatively large coupling constant as well as a significant kinetic mixing with U(1Y. With the large kinetic mixing, the standard model gauge couplings unify around 1017 GeV, suggesting the grand unified theory without too rapid proton decay. Our scenario predicts events with a photon and missing transverse momentum, and its cross section is related to that for the diphoton excess through the kinetic mixing. We also discuss other possible collider signatures and cosmology, including various ways to evade constraints on exotic stable charged particles. In some cases where the 750 GeV diphoton excess is due to diaxion decays, our scenario also predicts triphoton and tetraphoton signals.
Dirac dark matter and b →s ℓ+ℓ- with U(1) gauge symmetry
Celis, Alejandro; Feng, Wan-Zhe; Vollmann, Martin
2017-02-01
We revisit the possibility of a Dirac fermion dark matter candidate in the light of current b →s ℓ+ℓ- anomalies by investigating a minimal extension of the Standard Model with a horizontal U(1 ) ' local symmetry. Dark matter stability is protected by a remnant Z2 symmetry arising after spontaneous symmetry breaking of U(1 ) '. The associated Z' gauge boson can accommodate current hints of new physics in b →s ℓ+ℓ- decays, and acts as a vector portal between dark matter and the visible sector. We find that the model is severely constrained by a combination of precision measurements at flavor factories, LHC searches for dilepton resonances, as well as direct and indirect dark matter searches. Despite this, viable regions of the parameter space accommodating the observed dark matter relic abundance and the b →s ℓ+ℓ-anomalies still persist for dark matter and Z ' masses in the TeV range.
Program package for multicanonical simulations of U(1) lattice gauge theory-Second version
Bazavov, Alexei; Berg, Bernd A.
2013-03-01
A new version STMCMUCA_V1_1 of our program package is available. It eliminates compatibility problems of our Fortran 77 code, originally developed for the g77 compiler, with Fortran 90 and 95 compilers. New version program summaryProgram title: STMC_U1MUCA_v1_1 Catalogue identifier: AEET_v1_1 Licensing provisions: Standard CPC license, http://cpc.cs.qub.ac.uk/licence/licence.html Programming language: Fortran 77 compatible with Fortran 90 and 95 Computers: Any capable of compiling and executing Fortran code Operating systems: Any capable of compiling and executing Fortran code RAM: 10 MB and up depending on lattice size used No. of lines in distributed program, including test data, etc.: 15059 No. of bytes in distributed program, including test data, etc.: 215733 Keywords: Markov chain Monte Carlo, multicanonical, Wang-Landau recursion, Fortran, lattice gauge theory, U(1) gauge group, phase transitions of continuous systems Classification: 11.5 Catalogue identifier of previous version: AEET_v1_0 Journal Reference of previous version: Computer Physics Communications 180 (2009) 2339-2347 Does the new version supersede the previous version?: Yes Nature of problem: Efficient Markov chain Monte Carlo simulation of U(1) lattice gauge theory (or other continuous systems) close to its phase transition. Measurements and analysis of the action per plaquette, the specific heat, Polyakov loops and their structure factors. Solution method: Multicanonical simulations with an initial Wang-Landau recursion to determine suitable weight factors. Reweighting to physical values using logarithmic coding and calculating jackknife error bars. Reasons for the new version: The previous version was developed for the g77 compiler Fortran 77 version. Compiler errors were encountered with Fortran 90 and Fortran 95 compilers (specified below). Summary of revisions: epsilon=one/10**10 is replaced by epsilon/10.0D10 in the parameter statements of the subroutines u1_bmha.f, u1_mucabmha.f, u1wl
New hierarchy in GUTs based on SU(n,1)/SU(n)U(1) SUGRA
International Nuclear Information System (INIS)
Hayashi, M.J.; Murayama, Akihiro
1985-01-01
Grand unified theories (GUTs) in the framework of SU(n, 1)/SU(n) x U(1) supergravity are discussed which naturally generate a new hierarchy, Msub(P) (Planck mass): Msub(X) (GUT scale):msub(3/2) (gravitino mass):m (explicit supersymmetry breaking scale)=1:epsilon:epsilon 3 :epsilon 5 α(Msub(X)) with Msub(P) as the only input mass scale. The SUSY breaking scale m is expected to be fixed radiatively as mproportionalMsub(W), i.e., epsilonproportional10 -3 . Our method would be applicable to any GUT based on SU(n, 1)/SU(n) x U(1) supergravity. (orig.)
Dark gauge U(1) symmetry for an alternative left-right model
Energy Technology Data Exchange (ETDEWEB)
Kownacki, Corey; Ma, Ernest; Pollard, Nicholas; Popov, Oleg; Zakeri, Mohammadreza [University of California, Department of Physics and Astronomy, Riverside, CA (United States)
2018-02-15
An alternative left-right model of quarks and leptons, where the SU(2){sub R} lepton doublet (ν, l){sub R} is replaced with (n, l){sub R} so that n{sub R} is not the Dirac mass partner of ν{sub L}, has been known since 1987. Previous versions assumed a global U(1){sub S} symmetry to allow n to be identified as a dark-matter fermion. We propose here a gauge extension by the addition of extra fermions to render the model free of gauge anomalies, and just one singlet scalar to break U(1){sub S}. This results in two layers of dark matter, one hidden behind the other. (orig.)
Non(anti)commutative N = (1,1/2) supersymmetric U(1) gauge theory
International Nuclear Information System (INIS)
Araki, Takeo; Ito, Katsushi; Ohtsuka, Akihisa
2005-01-01
We study a reduction of deformation parameters in non(anti)commutative N = 2 harmonic superspace to those in non(anti)commutative N = 1 superspace. By this reduction we obtain the exact gauge and supersymmetry transformations in the Wess-Zumino gauge of non(anti)commutative N = 2 supersymmetric U(1) gauge theory defined in the deformed harmonic superspace. We also find that the action with the first order correction in the deformation parameter reduces to the one in the N = 1 superspace by some field redefinition. We construct deformed N = (1,1/2) supersymmetry in N = 2 supersymmetric U(1) gauge theory in non(anti)commutative N = 1 superspace
Testable flipped SU(5)xU(1){sub X} models
Energy Technology Data Exchange (ETDEWEB)
Jiang Jing [Institute of Theoretical Science, University of Oregon, Eugene, OR 97403 (United States); Li Tianjun [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States) and Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080 (China) and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854 (United States)]. E-mail: tjli@physics.rutgers.edu; Nanopoulos, Dimitri V. [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States); Astroparticle Physics Group, Houston Advanced Research Center (HARC), Mitchell Campus, Woodlands, TX 77381 (United States); Academy of Athens, Division of Natural Sciences, 28 Panepistimiou Avenue, Athens 10679 (Greece)
2007-06-11
The little hierarchy between the GUT scale and the string scale may give us some hints that can be tested at the LHC. To achieve string-scale gauge coupling unification, we introduce additional vector-like particles. We require that these vector-like particles be standard, form complete GUT multiplets, and have masses around the TeV scale or close to the string scale. Interestingly, only the flipped SU(5)xU(1){sub X} models can work elegantly. We consider all possible sets of vector-like particles with masses around the TeV scale. And we introduce vector-like particles with masses close to the string scale which can mimic the string-scale threshold corrections. We emphasize that all of these vector-like particles can be obtained in the interesting flipped SU(5)xU(1){sub X} string models from the four-dimensional free fermionic string construction. Assuming the low-energy supersymmetry, high-scale supersymmetry, and split supersymmetry, we show that the string-scale gauge coupling unification can indeed be achieved in the flipped SU(5)xU(1){sub X} models. These models can be tested at the LHC by observing simple sets of vector-like particles at the TeV scale. Moreover, we discuss a simple flipped SU(5)xU(1){sub X} model with string-scale gauge coupling unification and high-scale supersymmetry by introducing only one pair of the vector-like particles at the TeV scale, and we predict the corresponding Higgs boson masses. Also, we briefly comment on the string-scale gauge coupling unification in the model with low-energy supersymmetry by introducing only one pair of the vector-like particles at the intermediate scale. And we briefly comment on the mixings among the SM fermions and the corresponding extra vector-like particles.
Neutrino masses, dark matter and leptogenesis with U(1) B - L gauge symmetry
Geng, Chao-Qiang; Okada, Hiroshi
2018-06-01
We propose a model with an U(1) B - L gauge symmetry, in which small neutrino masses, dark matter and the matter-antimatter asymmetry in the Universe can be simultaneously explained. In particular, the neutrino masses are generated radiatively, while the matter-antimatter asymmetry is led by the leptogenesis mechanism, at TeV scale. We also explore allowed regions of the model parameters and discuss some phenomenological effects, including lepton flavor violating processes.
Radiative corrections in SU2 x U1 LEP/SLC
International Nuclear Information System (INIS)
Lynn, B.W.; Peskin, M.E.; Stuart, R.G.
1985-06-01
We show the sensitivity of various experimental measurements to one-loop radiative corrections in SU 2 x U 1 . Models considered are the standard GSW model as well as extensions of it which include extra quarks and leptons, SUSY and certain technicolor models. The observation of longitudinal polarization is a great help in seeing these effects in asymmetries in e + e - → μ + μ - , tau + tau - on Z 0 resonance. 25 refs., 22 figs., 10 tabs
On bound states of photons in noncommutative U(1) gauge theory
International Nuclear Information System (INIS)
Fatollahi, A.H.; Jafari, A.
2006-01-01
We consider the possibility that photons of noncommutative U(1) gauge theory can make bound states. Using the potential model, developed based on the constituent gluon picture of QCD glue-balls, arguments are presented in favor of the existence of these bound states. The basic ingredient of the potential model is that the self-interacting massless gauge particles may get mass by the inclusion of non-perturbative effects. (orig.)
Nuclear matter saturation in a U(1) circle-times chiral model
International Nuclear Information System (INIS)
Lin, Wei
1989-01-01
The mean-field approximation in the U(1) circle-times chiral model for nuclear matter maturation is reviewed. Results show that it cannot be the correct saturation mechanism. It is argued that in this chiral model, other than the fact the ω mass can depend on the density of nuclear matter, saturation is still quite like the Walecka picture. 16 refs., 3 figs
Dilatometric Study Of U1-xAmxO2±δ Transmutation Fuels
International Nuclear Information System (INIS)
Lebreton, Florent; Horlait, Denis; Delahaye, Thibaud; Blanchart, P.
2013-01-01
Conclusions - Dilatometric study results: • Reactive sintering: competition between solidsolution formation and densification process → the latter is slowed down and final density limited; • Conventional sintering: avoids this competition → higher densities are reached. - New homogeneous U 1-x Am x O 2±δ precursors: • Powders synthesized by oxalate co-conversion; • Microspheres formed using the CRMP (WAR-like) process
Slavnov and Gaudin-Korepin Formulas for Models without U(1) Symmetry: the Twisted XXX Chain
Belliard, Samuel; Pimenta, Rodrigo A.
2015-12-01
We consider the XXX spin-1/2 Heisenberg chain on the circle with an arbitrary twist. We characterize its spectral problem using the modified algebraic Bethe anstaz and study the scalar product between the Bethe vector and its dual. We obtain modified Slavnov and Gaudin-Korepin formulas for the model. Thus we provide a first example of such formulas for quantum integrable models without U(1) symmetry characterized by an inhomogenous Baxter T-Q equation.
Heavy charged leptons in an SU(3)L x U(1)N model
International Nuclear Information System (INIS)
Pleitez, V.; Tonasse, M.D.
1992-12-01
An SU(3) L x U(1) N model for the electroweak interactions which includes additional heavy charged leptons is considered. These leptons have not strong constraints on their masses since they do not couple in the same way as the lightest leptons to the neutral-currents and also because new contributions to the muon g-2 factor already suppressed because of the massive new vector boson present in this model. (author)
Zee-Babu type model with U (1 )Lμ-Lτ gauge symmetry
Nomura, Takaaki; Okada, Hiroshi
2018-05-01
We extend the Zee-Babu model, introducing local U (1 )Lμ-Lτ symmetry with several singly charged bosons. We find a predictive neutrino mass texture in a simple hypothesis in which mixings among singly charged bosons are negligible. Also, lepton-flavor violations are less constrained compared with the original model. Then, we explore the testability of the model, focusing on doubly charged boson physics at the LHC and the International Linear Collider.
New scotogenic model of neutrino mass with U(1){sub D} gauge interaction
Energy Technology Data Exchange (ETDEWEB)
Ma, Ernest [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); Picek, Ivica; Radovčić, Branimir [Department of Physics, Faculty of Science, University of Zagreb, P.O.B. 331, HR-10002 Zagreb (Croatia)
2013-11-04
We propose a new realization of the one-loop radiative model of neutrino mass generated by dark matter (scotogenic), where the particles in the loop have an additional U(1){sub D} gauge symmetry, which may be exact or broken to Z{sub 2}. This model is relevant to a number of astrophysical observations, including AMS-02 and the dark-matter distribution in dwarf galactic halos.
Neutrinoless double beta decay in an SU(3)L x U(1)N model
International Nuclear Information System (INIS)
Pleitez, V.; Tonasse, M.D.
1993-01-01
A model for the electroweak interactions with SU (3) L x U(1) N gauge symmetry is considered. It is shown that, it is the conservation of F = L + B which forbids massive neutrinos and the neutrinoless double beta decay, (β β) On u. Explicit and spontaneous breaking of F imply that the neutrinos have an arbitrary mass and (β β) On u proceeds also with some contributions that do not depend explicitly on the neutrino mass. (author)
Kinetic mixing of the photon with hidden U(1)s in string phenomenology
International Nuclear Information System (INIS)
Abel, S.A.; Khoze, V.V.; Jaeckel, J.
2008-03-01
Embeddings of the standard model in type II string theory typically contain a variety of U(1) gauge factors arising from D-branes in the bulk. In general, there is no reason why only one of these - the one corresponding to weak hypercharge - should be massless. Observations require that standard model particles must be neutral (or have an extremely small charge) under additional massless U(1)s, i.e. the latter have to belong to a so called hidden sector. The exchange of heavy messengers, however, can lead to a kinetic mixing between the hypercharge and the hidden-sector U(1)s, that is testable with near future experiments. This provides a powerful probe of the hidden sectors and, as a consequence, of the string theory realisation itself. In the present paper, we show, using a variety of methods, how the kinetic mixing can be derived from the underlying type II string compactification, involving supersymmetric and nonsupersymmetric configurations of D-branes, both in large volumes and in warped backgrounds with fluxes. We first demonstrate by explicit example that kinetic mixing occurs in a completely supersymmetric set-up where we can use conformal field theory techniques. We then develop a supergravity approach which allows us to examine the phenomenon in more general backgrounds, where we find that kinetic mixing is natural in the context of flux compactifications. We discuss the phenomenological consequences for experiments at the low-energy frontier, searching for signatures of light, sub-electronvolt or even massless hidden-sector U(1) gauge bosons and minicharged particles. (orig.)
Kinetic mixing of the photon with hidden U(1)s in string phenomenology
Energy Technology Data Exchange (ETDEWEB)
Abel, S.A.; Khoze, V.V. [Durham Univ. (United Kingdom). Inst. for Particle Physics Phenomenology; Goodsell, M.D. [Laboratoire de Physique Theorique et Hautes Energies, Paris (France); Jaeckel, J. [Durham Univ. (United Kingdom). Inst. for Particle Physics Phenomenology]|[Heidelberg Univ. (Germany). Inst. fuer Theoretische Physik; Ringwald, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2008-03-15
Embeddings of the standard model in type II string theory typically contain a variety of U(1) gauge factors arising from D-branes in the bulk. In general, there is no reason why only one of these - the one corresponding to weak hypercharge - should be massless. Observations require that standard model particles must be neutral (or have an extremely small charge) under additional massless U(1)s, i.e. the latter have to belong to a so called hidden sector. The exchange of heavy messengers, however, can lead to a kinetic mixing between the hypercharge and the hidden-sector U(1)s, that is testable with near future experiments. This provides a powerful probe of the hidden sectors and, as a consequence, of the string theory realisation itself. In the present paper, we show, using a variety of methods, how the kinetic mixing can be derived from the underlying type II string compactification, involving supersymmetric and nonsupersymmetric configurations of D-branes, both in large volumes and in warped backgrounds with fluxes. We first demonstrate by explicit example that kinetic mixing occurs in a completely supersymmetric set-up where we can use conformal field theory techniques. We then develop a supergravity approach which allows us to examine the phenomenon in more general backgrounds, where we find that kinetic mixing is natural in the context of flux compactifications. We discuss the phenomenological consequences for experiments at the low-energy frontier, searching for signatures of light, sub-electronvolt or even massless hidden-sector U(1) gauge bosons and minicharged particles. (orig.)
Crystallo-chemistry of actinide nitrides (U1-yPuy)N and effect of impurities
International Nuclear Information System (INIS)
Beauvy, M.; Coulon-Picard, E.; Pelletier, M.
2004-01-01
Investigations on actinide nitrides has been done in our Laboratories for Fast Breeder Reactors since the seventies and some properties are reported to show the interest for these fuels. Today, the actinide nitrides are reconsidered as possible fuels for the future fission reactors (GFR and LMFR selected by the international forum Generation IV). The results of new investigations on crystal structure of mixed mono-nitrides (U,Pu)N, and the effects of oxygen and carbon contaminations on this structure are presented. The cubic 'NaCl-fcc' type structure of actinide nitrides AnN with space group O5/h-Fm3m does not respect the 'Vegard law' model for the mixed nitrides (U 1-y Pu y )N. These nitrides are usually considered with strong metallic character associated with partial ionic bonding, but the ionic contribution in the An-N bonding determined in this work is very important and near 41.6% for UN and PuN. From results published on resistivity of mixed nitrides, the data on bonding must be also modified for partial covalence. This is in good agreement with the experimental lattice parameters which are not compatible with dominant metallic bonding. The numbers of bonding electrons in the nitrides (U 1-y Pu y )N are reevaluated and the low values proposed comparatively with those previously published confirm the strong ionic character with high concentration of An 3+ ions. The solubility of oxygen and carbon in actinide nitrides (U 1-y Pu y )N are discussed from measurements on volume concentration of actinide oxide phase, total oxygen and carbon contents, and lattice parameter of nitrides. The oxygen solubility limit in UN is near 1000 ppm, with a lightly higher value of 1200 ppm for the mixed nitride (U 0.8 Pu 0.2 )N. The effects of oxygen or carbon atoms in the lattice of (U 1-y Pu y )N are analysed
Phenomenological implications of the flipped SU(5) x U(1) superstring model
Energy Technology Data Exchange (ETDEWEB)
Tamvakis, K. (Physics Dept., Univ. of Ioannina (Greece))
1991-07-01
We study in detail gauge symmetry breaking in the SU(5)xU(1)'xU(1){sup 4}xSO(10)xSO(6) superstring model, solving the D and F-flatness conditions and taking into account quartic and quintic superpotential terms. We find that, to this order, the model describes two massive generations of quarks and leptons as well as a massless generation expected to receive naturally suppressed masses from higher order non-renormalizable terms. D and F-flatness restricts the number of massless isodoublets to four. We solve the coupled renormalization group equations for the gauge and Yukawa couplings in the two-loop approximation and obtain the top-quark mass as a function of two parameters of the model which could be chosen to be ratios of singlet v.e.v's associated with the surplus (U(1)){sup 4} breaking. We obtain a heavy top-quark with 150GeV {<=} m{sub 1} < 200GeV, for most part of the parameter space, while lower values are possible only in a very small extermal region. We also compute the allowed range of unification parameters (M{sub x}, sin{sup 2} {theta}{sub w}, {alpha}{sub 3}(M{sub w})) in the presence of a heavy top quark. (orig.).
Neutrino mass, leptogenesis and FIMP dark matter in a U(1){sub B-L} model
Energy Technology Data Exchange (ETDEWEB)
Biswas, Anirban; Khan, Sarif [Harish-Chandra Research Institute, Allahabad (India); Homi Bhabha National Institute, Training School Complex, Mumbai (India); Choubey, Sandhya [Harish-Chandra Research Institute, Allahabad (India); Homi Bhabha National Institute, Training School Complex, Mumbai (India); AlbaNova University Center, Department of Theoretical Physics, School of Engineering Sciences, KTH Royal Institute of Technology, Stockholm (Sweden)
2017-12-15
The Standard Model (SM) is inadequate to explain the origin of tiny neutrino masses, the dark matter (DM) relic abundance and the baryon asymmetry of the Universe. In this work, to address all three puzzles, we extend the SM by a local U(1){sub B-L} gauge symmetry, three right-handed (RH) neutrinos for the cancellation of gauge anomalies and two complex scalars having non-zero U(1){sub B-L} charges. All the newly added particles become massive after the breaking of the U(1){sub B-L} symmetry by the vacuum expectation value (VEV) of one of the scalar fields φ{sub H}. The other scalar field, φ{sub DM}, which does not have any VEV, becomes automatically stable and can be a viable DM candidate. Neutrino masses are generated using the Type-I seesaw mechanism, while the required lepton asymmetry to reproduce the observed baryon asymmetry can be attained from the CP violating out of equilibrium decays of the RH neutrinos in TeV scale. More importantly within this framework, we study in detail the production of DM via the freeze-in mechanism considering all possible annihilation and decay processes. Finally, we find a situation when DM is dominantly produced from the annihilation of the RH neutrinos, which are at the same time also responsible for neutrino mass generation and leptogenesis. (orig.)
Neutrino mass, leptogenesis and FIMP dark matter in a U(1)_{B-L} model
Biswas, Anirban; Choubey, Sandhya; Khan, Sarif
2017-12-01
The Standard Model (SM) is inadequate to explain the origin of tiny neutrino masses, the dark matter (DM) relic abundance and the baryon asymmetry of the Universe. In this work, to address all three puzzles, we extend the SM by a local U(1)_{B-L} gauge symmetry, three right-handed (RH) neutrinos for the cancellation of gauge anomalies and two complex scalars having non-zero U(1)_{B-L} charges. All the newly added particles become massive after the breaking of the U(1)_{B-L} symmetry by the vacuum expectation value (VEV) of one of the scalar fields φ _H. The other scalar field, φ _DM, which does not have any VEV, becomes automatically stable and can be a viable DM candidate. Neutrino masses are generated using the Type-I seesaw mechanism, while the required lepton asymmetry to reproduce the observed baryon asymmetry can be attained from the CP violating out of equilibrium decays of the RH neutrinos in TeV scale. More importantly within this framework, we study in detail the production of DM via the freeze-in mechanism considering all possible annihilation and decay processes. Finally, we find a situation when DM is dominantly produced from the annihilation of the RH neutrinos, which are at the same time also responsible for neutrino mass generation and leptogenesis.
Supersymmetric codimension-two branes and U(1)R mediation in 6D gauged supergravity
International Nuclear Information System (INIS)
Lee, Hyun Min
2008-01-01
We construct a consistent supersymmetric action for brane chiral and vector multiplets in a six-dimensional chiral gauged supergravity. A nonzero brane tension can be accommodated by allowing for a brane-localized Fayet-Iliopoulos term proportional to the brane tension. When the brane chiral multiplet is charged under the bulk U(1) R , we obtain a nontrivial coupling to the extra component of the U(1) R gauge field strength and a singular scalar self-interaction term. Dimensionally reducing to 4D on a football supersymmetric solution, we discuss the implication of such interactions for obtaining the U(1) R D-term in the 4D effective supergravity. By assuming the bulk gaugino condensates and nonzero brane F- and/or D-term for the uplifting potential, we have all the moduli stabilized with a vanishing cosmological constant. The brane scalar with nonzero R charge then gets a soft mass of order the gravitino mass. The overall sign of the soft mass squared depends on the sign of the R charge as well as whether the brane F- or D-term dominates.
Quantitative SRXRF analysis on the BL15U1 beamline at SSRF
International Nuclear Information System (INIS)
Zhang Yanle; Yu Xiaohan
2010-01-01
In this paper, we give an introduction first to two quantification methods for synchrotron radiation X-ray fluorescence analysis (SRXRF), namely fundamental parameters method and Monte-Carlo simulation method, for their application on the BL15U1 beamline (hard X-ray microprobe) at SSRF (Shanghai Synchrotron Radiation Facility). Effectiveness of the two methods is demonstrated and the XRF detection limits of the BL15U1 beamline are calculated. The results show that, quantitative analysis at the ppm level can be done using the two methods, with an accuracy of better than 10%. Although both the methods are valid for the SRXRF data analysis,the Monte Carlo method gives better analysis result, as it compares the simulated spectrum with the experiment spectrum, and this helps the determination of experiment parameters and thus minimizes the error caused by incorrect parameters. Finally, the detection limits shows that the BL15U1 beamline is capable of carrying out standard-of-the-art XRF experiment. (authors)
Critical behavior of the compact 3D U(1) gauge theory on isotropic lattices
International Nuclear Information System (INIS)
Borisenko, O; Fiore, R; Papa, A; Gravina, M
2010-01-01
We report on the computation of the critical point of the deconfinement phase transition, critical indices and the string tension in the compact three-dimensional U(1) lattice gauge theory at finite temperatures. The critical indices govern the behavior across the deconfinement phase transition in the pure gauge U(1) model and are generally expected to coincide with the critical indices of the two-dimensional XY model. We studied numerically the U(1) model for N t = 8 on lattices with spatial extension ranging from L = 32 to 256. Our determination of the infinite volume critical point on the lattice with N t = 8 differs substantially from the pseudo-critical coupling at L = 32, found earlier in the literature and implicitly assumed as the onset value of the deconfined phase. The critical index ν computed from the scaling of the pseudo-critical couplings with the extension of the spatial lattice agrees well with the XY value ν = 1/2. On the other hand, the index η shows large deviation from the expected universal value. The possible reasons for such behavior are discussed in detail
B-meson anomalies and Higgs physics in flavored U(1)' model
Bian, Ligong; Lee, Hyun Min; Park, Chan Beom
2018-04-01
We consider a simple extension of the Standard Model with flavor-dependent U(1)', that has been proposed to explain some of B-meson anomalies recently reported at LHCb. The U(1)' charge is chosen as a linear combination of anomaly-free B_3-L_3 and L_μ -L_τ . In this model, the flavor structure in the SM is restricted due to flavor-dependent U(1)' charges, in particular, quark mixings are induced by a small vacuum expectation value of the extra Higgs doublet. As a result, it is natural to get sizable flavor-violating Yukawa couplings of heavy Higgs bosons involving the bottom quark. In this article, we focus on the phenomenology of the Higgs sector of the model including extra Higgs doublet and singlet scalars. We impose various bounds on the extended Higgs sector from Higgs and electroweak precision data, B-meson mixings and decays as well as unitarity and stability bounds, then discuss the productions and decays of heavy Higgs bosons at the LHC.
Mixed Mediation of Supersymmetry Breaking in Models with Anomalous U(1) Gauge Symmetry
International Nuclear Information System (INIS)
Choi, Kiwoon
2010-01-01
There can be various built-in sources of supersymmetry breaking in models with anomalous U(1) gauge symmetry, e.g. the U(1) D-term, the F-components of the modulus superfield required for the Green-Schwarz anomaly cancellation mechanism and the chiral matter superfields required to cancel the Fayet-Iliopoulos term, and finally the supergravity auxiliary component which can be parameterized by the F-component of chiral compensator. The relative strength between these supersymmetry breaking sources depends crucially on the characteristics of D-flat direction and also on how the D-flat direction is stabilized at a vacuum with nearly vanishing cosmological constant. We examine the possible pattern of the mediation of supersymmetry breaking in models with anomalous U(1) gauge symmetry, and find that various different mixed mediation scenarios can be realized, including the mirage mediation which corresponds to a mixed modulus-anomaly mediation, D-term domination giving a split sparticle spectrum, and also a mixed gauge-D-term mediation scenario.
Functional organization of the Sm core in the crystal structure of human U1 snRNP.
Weber, G.; Trowitzsch, S.; Kastner, B.; Lührmann, R.; Wahl, M.
2010-01-01
The U1 small nuclear ribonucleoprotein initiates the assembly of the spliceosome. Here, the structure of the natively purified U1 small nuclear ribonucleoprotein particle reveals the core Sm protein ring and its interactions with the Sm site in the small nuclear RNA.
Peccei-Quinn invariant singlet extended SUSY with anomalous U(1) gauge symmetry
Energy Technology Data Exchange (ETDEWEB)
Im, Sang Hui; Seo, Min-Seok [Center for Theoretical Physics of the Universe, Institute for Basic Science (IBS),Daejeon 305-811 (Korea, Republic of)
2015-05-13
Recent discovery of the SM-like Higgs boson with m{sub h}≃125 GeV motivates an extension of the minimal supersymmetric standard model (MSSM), which involves a singlet Higgs superfield with a sizable Yukawa coupling to the doublet Higgs superfields. We examine such singlet-extended SUSY models with a Peccei-Quinn (PQ) symmetry that originates from an anomalous U(1){sub A} gauge symmetry. We focus on the specific scheme that the PQ symmetry is spontaneously broken at an intermediate scale v{sub PQ}∼√(m{sub SUSY}M{sub Pl}) by an interplay between Planck scale suppressed operators and tachyonic soft scalar mass m{sub SUSY}∼√(D{sub A}) induced dominantly by the U(1){sub A}D-term D{sub A}. This scheme also results in spontaneous SUSY breaking in the PQ sector, generating the gaugino masses M{sub 1/2}∼√(D{sub A}) when it is transmitted to the MSSM sector by the conventional gauge mediation mechanism. As a result, the MSSM soft parameters in this scheme are induced mostly by the U(1){sub A}D-term and the gauge mediated SUSY breaking from the PQ sector, so that the sparticle masses can be near the present experimental bounds without causing the SUSY flavor problem. The scheme is severely constrained by the condition that a phenomenologically viable form of the low energy operators of the singlet and doublet Higgs superfields is generated by the PQ breaking sector in a way similar to the Kim-Nilles solution of the μ problem, and the resulting Higgs mass parameters allow the electroweak symmetry breaking with small tan β. We find two minimal models with two singlet Higgs superfields, satisfying this condition with a relatively simple form of the PQ breaking sector, and briefly discuss some phenomenological aspects of the model.
Superheavy contributions to FCNC in the flipped SU(5) x U(1)
Energy Technology Data Exchange (ETDEWEB)
Gabbiani, F.; Masiero, A.
1988-08-04
In the supersymmetric GUT's the presence of the superheavy fields yields new contributions to flavour-changing neutral-current effects at low energy. We analyse this phenomenon in the context of the flipped SU(5) x U(1) superstring (-inspired) model. We show that possibly sizeable flavour leptonic changes (..mu.. -> e..gamma.., ..mu.. -> eeanti e, ..mu..-e conversion in nuclei) are generated. K-anti K, B-anti B mixings and b -> s..gamma.. constrain new couplings at the superlarge scale, which are unrelated to the standard Yukawa coefficients.
Constraints from proton decay in the flipped SU(5)xU(1) superstring model
Energy Technology Data Exchange (ETDEWEB)
Leontaris, G.K.; Tamvakis, K. (Ioannina Univ. (Greece). Theoretical Physics Div.)
1991-05-16
We discuss the constraints the emerge from the existence of dimension-5 baryon-violating operators in the flipped SU(5) x U(1) superstring model. These are constraints on matter field assignments and on singlet VEV values. Although baryon-violating dimension-5 operators that appear as quintic non-renormalizable terms vanish as has been proven before and as we verify here, effective dimension-5 operators resulting from Higgs exchange put non-trivial but feasible constraints on the model. Constraints are also extracted from the presence of higher order non-renormalizable terms that generate such operators which do not a priori vanish. (orig.).
U(1) current from the AdS/CFT: diffusion, conductivity and causality
Energy Technology Data Exchange (ETDEWEB)
Bu, Yanyan [Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Lublinsky, Michael [Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Physics Department, University of Connecticut, 2152 Hillside Road, Storrs, CT 06269-3046 (United States); Sharon, Amir [Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel)
2016-04-21
For a holographically defined finite temperature theory, we derive an off-shell constitutive relation for a global U(1) current driven by a weak external non-dynamical electromagnetic field. The constitutive relation involves an all order gradient expansion resummed into three momenta-dependent transport coefficient functions: diffusion, electric conductivity, and “magnetic” conductivity. These transport functions are first computed analytically in the hydrodynamic limit, up to third order in the derivative expansion, and then numerically for generic values of momenta. We also compute a diffusion memory function, which, as a result of all order gradient resummation, is found to be causal.
International Nuclear Information System (INIS)
Neves, A.G.M.
1988-01-01
The renormalization transformation e sup(-S 1) sup((B)) const. ζ e sup(-S o (A) - V(A)) δ (B-C sub(1) A) δ sub(Ax) (A)DA for the U(1) lattice gauge theory, where S sub(o) (A) is the gaussian fixed point of the transformation, V(A) is a gauge invariant perturbation, C sub(1) is the averaging operator and δ sub(Ax) (A) fixes the local axial gauge is studied via an equivalent renormalization transformation on the 2-forms F = dA. The transformation is linearized in the neighborhood of the fixed point and then diagonalized. (author)
Constructive tensorial group field theory I: The {U(1)} -{T^4_3} model
Lahoche, Vincent
2018-05-01
The loop vertex expansion (LVE) is a constructive technique using canonical combinatorial tools. It works well for quantum field theories without renormalization, which is the case of the field theory studied in this paper. Tensorial group field theories (TGFTs) are a new class of field theories proposed to quantize gravity. This paper is devoted to a very simple TGFT for rank three tensors with U(1) group and quartic interactions, hence nicknamed -. It has no ultraviolet divergence, and we show, with the LVE, that it is Borel summable in its coupling constant.
U(1)R mediation from the flux compactification in six dimensions
International Nuclear Information System (INIS)
Lee, Hyun Min
2008-01-01
We consider a supersymmetric completion of codimension-two branes with nonzero tension in a 6D gauged supergravity. As a consequence, we obtain the football solution with 4D Minkowski space as a new supersymmetric background that preserves 4D N = 1 SUSY. In the presence of brane multiplets, we derive the 4D effective supergravity action for the football background and show that the remaining modulus can be stabilized by a bulk non-perturbative correction with brane uplifting potentials at a zero vacuum energy. We find that the U(1) R mediation can be a dominant source of SUSY breaking for a brane scalar with nonzero R charge.
Bistate t-expansion study of U(1) lattice gauge theory in 2+1 dimensions
International Nuclear Information System (INIS)
Morningstar, C.J.
1992-01-01
The compact formulation of U(1) Hamiltonian lattice gauge theory in 2+1 dimensions is studied using the t expansion. The ground-state energy, average plaquette, specific heat, photon mass gap, and the ratio of the two lowest masses are investigated. Two contraction techniques are applied: a unistate scheme which uses only the strong-coupling vacuum for the trial state, and a bistate scheme which allows the introduction of variational parameters and arbitrarily large loops of electric flux in one of the trial states. The mass ratio obtained from the bistate contraction scheme exhibits precocious scaling. No evidence of a stable scalar glueball is found
Hairy black hole solutions in U(1) gauge-invariant scalar-vector-tensor theories
Heisenberg, Lavinia; Tsujikawa, Shinji
2018-05-01
In U (1) gauge-invariant scalar-vector-tensor theories with second-order equations of motion, we study the properties of black holes (BH) on a static and spherically symmetric background. In shift-symmetric theories invariant under the shift of scalar ϕ → ϕ + c, we show the existence of new hairy BH solutions where a cubic-order scalar-vector interaction gives rise to a scalar hair manifesting itself around the event horizon. In the presence of a quartic-order interaction besides the cubic coupling, there are also regular BH solutions endowed with scalar and vector hairs.
Flux tubes in U(1) - Do they attract or repel each other?
International Nuclear Information System (INIS)
Zach, M.; Faber, M.; Skala, P.
1998-01-01
The dually transformed path integral of four-dimensional U(1) lattice gauge theory is used for a numerical investigation of multiply charged systems and the interaction between flux tubes. For this aim, it is convenient to implement periodically closed flux tubes (torelons) in the dual formulation. We calculate the free energy as well as the total electro-magnetic energy of doubly charged flux tubes as a function of the coupling β. The main results are that the string tension scales proportionally to the charge (contrary to the Coulomb potential) and in the range 0.9<β<1.0 we find a clear signal for attraction between flux tubes. (orig.)
A radiative neutrino mass model in light of DAMPE excess with hidden gauged U(1) symmetry
Nomura, Takaaki; Okada, Hiroshi; Wu, Peiwen
2018-05-01
We propose a one-loop induced neutrino mass model with hidden U(1) gauge symmetry, in which we successfully involve a bosonic dark matter (DM) candidate propagating inside a loop diagram in neutrino mass generation to explain the e+e‑ excess recently reported by the DArk Matter Particle Explorer (DAMPE) experiment. In our scenario dark matter annihilates into four leptons through Z' boson as DM DM → Z' Z' (Z' → l+ l‑) and Z' decays into leptons via one-loop effect. We then investigate branching ratios of Z' taking into account lepton flavor violations and neutrino oscillation data.
Loop calculations for the non-commutative U*(1) gauge field model with oscillator term
International Nuclear Information System (INIS)
Blaschke, Daniel N.; Grosse, Harald; Kronberger, Erwin; Schweda, Manfred; Wohlgenannt, Michael
2010-01-01
Motivated by the success of the non-commutative scalar Grosse-Wulkenhaar model, a non-commutative U * (1) gauge field theory including an oscillator-like term in the action has been put forward in (Blaschke et al. in Europhys. Lett. 79:61002, 2007). The aim of the current work is to analyze whether that action can lead to a fully renormalizable gauge model on non-commutative Euclidean space. In a first step, explicit one-loop graph computations are hence presented, and their results as well as necessary modifications of the action are successively discussed. (orig.)
Loop suppressed light fermion masses with U (1 )R gauge symmetry
Nomura, Takaaki; Okada, Hiroshi
2017-07-01
We propose a model with a two-Higgs doublet, where quark and charged-lepton masses in the first and second families are induced at one-loop level, and neutrino masses are induced at the two-loop level. In our model, we introduce an extra U (1 )R gauge symmetry that plays a crucial role in achieving desired terms in no conflict with anomaly cancellation. We show the mechanism to generate fermion masses, the resultant mass matrices, and Yukawa interactions in mass eigenstates, and we discuss several interesting phenomenologies such as the muon anomalous magnetic dipole moment and the dark matter candidate that arise from this model.
Hidden U (1 ) gauge symmetry realizing a neutrinophilic two-Higgs-doublet model with dark matter
Nomura, Takaaki; Okada, Hiroshi
2018-04-01
We propose a neutrinophilic two-Higgs-doublet model with hidden local U (1 ) symmetry, where active neutrinos are Dirac type, and a fermionic dark matter (DM) candidate is naturally induced as a result of remnant symmetry even after the spontaneous symmetry breaking. In addition, a physical Goldstone boson arises as a consequence of two types of gauge singlet bosons and contributes to the DM phenomenologies as well as an additional neutral gauge boson. Then, we analyze the relic density of DM within the safe range of direct detection searches and show the allowed region of dark matter mass.
U(1) current from the AdS/CFT: diffusion, conductivity and causality
International Nuclear Information System (INIS)
Bu, Yanyan; Lublinsky, Michael; Sharon, Amir
2016-01-01
For a holographically defined finite temperature theory, we derive an off-shell constitutive relation for a global U(1) current driven by a weak external non-dynamical electromagnetic field. The constitutive relation involves an all order gradient expansion resummed into three momenta-dependent transport coefficient functions: diffusion, electric conductivity, and “magnetic” conductivity. These transport functions are first computed analytically in the hydrodynamic limit, up to third order in the derivative expansion, and then numerically for generic values of momenta. We also compute a diffusion memory function, which, as a result of all order gradient resummation, is found to be causal.
Generalized permutation symmetry and the flavour problem in SU(2)sub(L)xU(1)
International Nuclear Information System (INIS)
Ecker, G.
1984-01-01
A generalized permutation group is introduced as a possible horizontal symmetry for SU(2)sub(L)xU(1) gauge theories. It leads to the unique two generation quark mass matrices with a correct prediction for the Cabibbo angle. For three generations the model exhibits spontaneous CP violation, correlates the Kobayashi-Maskawa mixing parameters s 1 and s 3 and predicts an upper bound for the running top quark mass of approximately 45 GeV. The hierarchy of generations is due to a hierarchy of vacuum expectation values rather than of Yukawa coupling constants. (orig.)
SU(2) x U(1) unified theory for charge, orbit and spin currents
International Nuclear Information System (INIS)
Jin Peiqing; Li Youquan; Zhang Fuchun
2006-01-01
Spin and charge currents in systems with Rashba or Dresselhaus spin-orbit couplings are formulated in a unified version of four-dimensional SU(2) x U(1) gauge theory, with U(1) being the Maxwell field and SU(2) being the Yang-Mills field. While the bare spin current is non-conserved, it is compensated by a contribution from the SU(2) gauge field, which gives rise to a spin torque in the spin transport, consistent with the semi-classical theory of Culcer et al. Orbit current is shown to be non-conserved in the presence of electromagnetic fields. Similar to the Maxwell field inducing forces on charge and charge current, we derive forces acting on spin and spin current induced by the Yang-Mills fields such as the Rashba and Dresselhaus fields and the sheer strain field. The spin density and spin current may be considered as a source generating Yang-Mills field in certain condensed matter systems
The neutralino sector in the U(1)-extended supersymmetric standard model
Energy Technology Data Exchange (ETDEWEB)
Choi, S.Y. [Chonbuk National Univ., Jeonju (Korea). Dept. of Physics and RIPC]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Haber, H.E. [California Univ., Santa Cruz, CA (United States). SCIPP; Kalinowski, J. [Warsaw Univ. (Poland). Inst. of Theoretical Physics; Zerwas, P.M. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[California Univ., Santa Cruz, CA (United States). SCIPP
2006-12-15
Motivated by grand unified theories and string theories we analyze the general structure of the neutralino sector in the USSM, an extension of the Minimal Supersymmetric Standard Model that involves a broken extra U(1) gauge symmetry. This supersymmetric U(1)-extended model includes an Abelian gauge superfield and a Higgs singlet superfield in addition to the standard gauge and Higgs superfields of the MSSM. The interactions between the MSSM fields and the new fields are in general weak and the mixing is small, so that the coupling of the two subsystems can be treated perturbatively. As a result, the mass spectrum and mixing matrix in the neutralino sector can be analyzed analytically and the structure of this 6-state system is under good theoretical control. We describe the decay modes of the new states and the impact of this extension on decays of the original MSSM neutralinos, including radiative transitions in cross-over zones. Production channels in cascade decays at the LHC and pair production at e{sup +}e{sup -} colliders are also discussed. (orig.)
Resolutions of Cn/Zn orbifolds, their U(1) bundles, and applications to string model building
International Nuclear Information System (INIS)
Nibbelink, Stefan Groot; Trapletti, Michele; Walter, Martin G.A.
2007-01-01
We describe blowups of C n /Z n orbifolds as complex line bundles over CP n-1 . We construct some gauge bundles on these resolutions. Apart from the standard embedding, we describe U(1) bundles and an SU(n-1) bundle. Both blowups and their gauge bundles are given explicitly. We investigate ten dimensional SO(32) super Yang-Mills theory coupled to supergravity on these backgrounds. The integrated Bianchi identity implies that there are only a finite number of U(1) bundle models. We describe how the orbifold gauge shift vector can be read off from the gauge background. In this way we can assert that in the blow down limit these models correspond to heterotic C 2 /Z 2 and C 3 /Z 3 orbifold models. (Only the Z 3 model with unbroken gauge group SO(32) cannot be reconstructed in blowup without torsion.) This is confirmed by computing the charged chiral spectra on the resolutions. The construction of these blowup models implies that the mismatch between type-I and heterotic models on T 6 /Z 3 does not signal a complication of S-duality, but rather a problem of type-I model building itself: The standard type-I orbifold model building only allows for a single model on this orbifold, while the blowup models give five different models in blow down
750 GeV resonance in the gauged U(1′-extended MSSM
Directory of Open Access Journals (Sweden)
Yun Jiang
2016-08-01
Full Text Available Recently the ATLAS and CMS Collaborations at the LHC announced their observation of a potential 750 GeV di-photon resonance, after analyzing the s=13 TeV LHC data. This observation has significant implications for low-energy supersymmetry. Beyond the MSSM and the NMSSM, we study the MSSM-extensions with an extra U(1′ gauge symmetry. The anomaly cancellation and the spontaneous breaking of the non-decoupled U(1′ generally require introducing vector-like supermultiplets (both colored and color-neutral ones and singlet supermultiplets, respectively. We illustrate that the potential 750 GeV resonance (Y can be accommodated in various mechanisms, as a singlet-like scalar or pseudoscalar. Three benchmark scenarios are presented: (1 vector-like quarks (VLQ mediated pp→Y→γγ; (2 scalar VLQ mediated pp→Y→γγ; (3 heavy scalar (pseudo-scalar H/A associated production pp→H⁎/A⁎→YH/h. Additionally, we notice that the Z′-mediated vector boson fusion production and Z′-associated production pp→Yqq′, if yielding a signal rate of the observed level, might have been excluded by the searches for Z′ via Drell–Yan process at the LHC.
Z-Z' mass hierarchy in a supersymmetric model with a secluded U(1)'-breaking sector
International Nuclear Information System (INIS)
Erler, Jens; Langacker, Paul; Li Tianjun
2002-01-01
We consider the Z ' /Z mass hierarchy in a supersymmetric model in which the U(1) ' is broken in a secluded sector coupled to the ordinary sector only by gauge and possibly soft terms. A large mass hierarchy can be achieved while maintaining the normal sparticle spectra if there is a direction in which the tree level potential becomes flat when a particular Yukawa coupling vanishes. We describe the conditions needed for the desired breaking pattern, to avoid unwanted global symmetries, and for an acceptable effective μ parameter. The electroweak breaking is dominated by A terms rather than scalar masses, leading to tan β≅1. The spectrum of the symmetry breaking sector is displayed. There is significant mixing between the MSSM particles and new standard model singlets, for both the Higgs scalars and the neutralinos. A larger Yukawa coupling for the effective μ parameter is allowed than in the NMSSM because of the U(1) ' contribution to the running from a high scale. The upper bound on the tree-level mass of the lightest CP even Higgs doublet mass is about cx174 GeV, where c is of order unity, but the actual mass eigenvalues are generally smaller because of singlet mixing
Hidden gauginos of an unbroken U(1): Cosmological constraints and phenomenological prospects
Energy Technology Data Exchange (ETDEWEB)
Ibarra, A. [Technische Univ. Muenchen, Garching (Germany). Physik-Department]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Ringwald, A.; Weniger, C. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2008-09-15
We study supersymmetric scenarios where the dark matter is the gaugino of an unbroken hidden U(1) which interacts with the visible world only via a small kinetic mixing with the hypercharge. Strong constraints on the parameter space can be derived from avoiding overclosure of the Universe and from requiring successful Big Bang Nucleosynthesis and structure formation. We find that for typical values of the mixing parameter, scenarios with neutralino NLSP are excluded, while scenarios with slepton NLSP are allowed when the mixing parameter lies in the range {chi} {proportional_to}O(10{sup -13}-10{sup -10}). We also show that if the gravitino is the LSP and the hidden U(1) gaugino the NLSP, the bounds on the reheating temperature from long lived charged MSSM relics can be considerably relaxed and we comment on the signatures of these scenarios at future colliders. Finally, we discuss the case of an anomalously small mixing, {chi} <<10{sup -16}, where the neutralino becomes a decaying dark matter candidate, and derive constraints from gamma ray experiments. (orig.)
Closing the SU(3)LxU(1)X symmetry at the electroweak scale
International Nuclear Information System (INIS)
Dias, Alex G.; Montero, J. C.; Pleitez, V.
2006-01-01
We show that some models with SU(3) C xSU(3) L xU(1) X gauge symmetry can be realized at the electroweak scale and that this is a consequence of an approximate global SU(2) L+R symmetry. This symmetry implies a condition among the vacuum expectation value of one of the neutral Higgs scalars, the U(1) X 's coupling constant, g X , the sine of the weak mixing angle sinθ W , and the mass of the W boson, M W . In the limit in which this symmetry is valid it avoids the tree level mixing of the Z boson of the standard model with the extra Z ' boson. We have verified that the oblique T parameter is within the allowed range indicating that the radiative corrections that induce such a mixing at the 1-loop level are small. We also show that a SU(3) L+R custodial symmetry implies that in some of the models we have to include sterile (singlets of the 3-3-1 symmetry) right-handed neutrinos with Majorana masses, since the seesaw mechanism is mandatory to obtain light active neutrinos. Moreover, the approximate SU(2) L+R subset of SU(3) L+R symmetry implies that the extra nonstandard particles of these 3-3-1 models can be considerably lighter than it had been thought before so that new physics can be really just around the corner
Why is Interstellar Object 1I/2017 U1 (`Oumuamua) Rocky, Tumbling and Possibly Very Prolate?
Katz, J. I.
2018-05-01
The recently discovered first interstellar object 1I/2017 U1 (`Oumuamua) has brightness that varies by a factor of 10, a range greater than that of any Solar System asteroid, a spectrum characteristic of Type D asteroids, and no evidence of evaporating volatiles, contrary to expectation for exo-Oort clouds. `Oumuamua is possibly the first example of the proposed "Jurads", objects depleted in volatiles and ejected from planetary systems during the post-main sequence evolution of their parent stars. I suggest that heating by the star's giant stage fluidized a precursor object as well as driving off any volatiles, causing it to assume the Jacobi ellipsoidal shape of a self-gravitating incompressible liquid. The collision that produced the inferred tumbling motion may have occurred thousands of years after the formation of 1I/2017 U1 `Oumuamua. Jacobi ellipsoids have a unique relation among rotation rate, density and axial ratio. The inferred axial ratio ⪆ 5 suggests a lower bound on the density of 1.6 g/cm3, apparently excluding an icy interior unless it is almost entirely frozen CO2. `Oumuamua may be related to accreting objects that pollute white dwarf atmospheres and that may make Soft Gamma Repeaters.
Reddy, A. S.; Czernik, A. J.; An, G.; Poovaiah, B. W.
1992-01-01
We cloned and sequenced a plant cDNA that encodes U1 small nuclear ribonucleoprotein (snRNP) 70K protein. The plant U1 snRNP 70K protein cDNA is not full length and lacks the coding region for 68 amino acids in the amino-terminal region as compared to human U1 snRNP 70K protein. Comparison of the deduced amino acid sequence of the plant U1 snRNP 70K protein with the amino acid sequence of animal and yeast U1 snRNP 70K protein showed a high degree of homology. The plant U1 snRNP 70K protein is more closely related to the human counter part than to the yeast 70K protein. The carboxy-terminal half is less well conserved but, like the vertebrate 70K proteins, is rich in charged amino acids. Northern analysis with the RNA isolated from different parts of the plant indicates that the snRNP 70K gene is expressed in all of the parts tested. Southern blotting of genomic DNA using the cDNA indicates that the U1 snRNP 70K protein is coded by a single gene.
U(1) x SU(2) Chern-Simons gauge theory of underdoped cuprate superconductors
International Nuclear Information System (INIS)
Marchetti, P.A.; Su Zhao-Bin; Yu Lu
1998-05-01
The Chern-Simons bosonization with U(1)xSU(2) gauge field is applied to the 2-D t-J model in the limit t>>J, to study the normal state properties of underdoped cuprate superconductors. We prove the existence of an upper bound on the partition function for holons in a spinon background, and we find the optimal spinon configuration saturating the upper bound on average - a coexisting flux phase and s+id-like RVB state. After neglecting the feedback of holon fluctuations on the U(1) field B and spinon fluctuations on the SU(2) field V, the holon field is a fermion and the spinon field is a hard-core boson. Within this approximation we show that the B field produces a π flux phase for the holons, converting them into Dirac-like fermions, while the V field, taking into account the feedback of holons produces a gap for the spinons vanishing in the zero doping limit. The nonlinear σ-model with a mass term describes the crossover from the short-ranged antiferromagnetic (AF) state in doped samples to long range AF order in reference compounds. Moreover, we derive a low-energy effective action in terms of spinons holons and a self-generated U(1) gauge field. Neglecting the gauge fluctuations, the holons are described by the Fermi liquid theory with a Fermi surface consisting of 4 ''half-pockets'' centered at (+-π/2,+-π/2) and one reproduces the results for the electron spectral function obtained in the mean field approximation, in agreement with the photoemission data on underdoped cuprates. The gauge fluctuations are not confining due to coupling to holons, but nevertheless yield an attractive interaction between spinons and holons leading to a bound state with electron quantum numbers. The renormalisation effects due to gauge fluctuations give rise to non-Fermi liquid behaviour for the composite electron, in certain temperature range showing the linear in T resistivity. This formalism provides a new interpretation of the spin gap in the underdoped superconductors
Lifting scalar-quark and -lepton masses with sideways U(1)-II
International Nuclear Information System (INIS)
McCabe, J.F.; Wada, W.W.
1984-01-01
We investigate the phenomenological consequences of an SUSY model with a gauged O'Raifeartaigh sector on scalar partner masses. The model has the gauge symmetry SU(5) x U(1). We find that this form of spontaneous SUSY breaking leads to large scalar partner masses through one loop graphs without changing quark and lepton masses from tree values, and without breaking SU(5) symmetries by the scalar partner sector. To calculate the scalar partner masses we extend previous work on supergraph techniques to include cases when SUSY is broken at tree level. We are able to sum exactly the corrections to unbroken propagators with the aid of a supersymmetric version of tree-level Dyson equations. We show how the same ideas can be implemented in an SU(5) gauge model where the normal Higgs give large masses radiatively to the scalar-quarks and -leptons. 7 references
Flavor violations in no-scale flipped SU(5)xU(1)
Energy Technology Data Exchange (ETDEWEB)
Faraggi, A.E.; Lopez, J.L.; Nonopoulos, D.V.; Yuan, K.
1989-05-04
We study lepton-number violations in the flipped SU(5)xU(1) model in the context of no-scale supergravity. We find that the experimental limits on ..mu..->e..gamma.., ..mu..->eeanti e, and ..mu.. conversion in nuclei generally imply an upper bound on the top quark mass and a lower bound on the gaugino mass. We conclude that the seed of supersymmetry breaking in no-scale models (gaugino masses) radically changes some results obtained in ''minimal'' N=1 supergravity in the leptonic sector, while results in the hadronic sector (e.g. K-anti K, B-anti B mixings, and b->s..gamma..) remain essentially unchanged.
Nano and micro U1-xThxO2 solid solutions: From powders to pellets
Balice, Luca; Bouëxière, Daniel; Cologna, Marco; Cambriani, Andrea; Vigier, Jean-François; De Bona, Emanuele; Sorarù, Gian Domenico; Kübel, Christian; Walter, Olaf; Popa, Karin
2018-01-01
Nuclear fuels production, structural materials, separation techniques, and waste management, all may benefit from an extensive knowledge in the nano-nuclear technology. In this line, we present here the production of U1-xThxO2 (x = 0 to 1) mixed oxides nanocrystals (NC's) through the hydrothermal decomposition of the oxalates in hot compressed water at 250 °C. Particles of spherical shape and size of about 5.5-6 nm are obtained during the hydrothermal decomposition process. The powdery nanocrystalline products were consolidated by spark plasma sintering into homogeneous mixed oxides pellets with grain sizes in the 0.4 to 5.5 μm range. Grain growth and mechanical properties were studied as a function of composition and size. No grain size effect was observed on the hardness or elastic modulus.
Renormalization of a tensorial field theory on the homogeneous space SU(2)/U(1)
Lahoche, Vincent; Oriti, Daniele
2017-01-01
We study the renormalization of a general field theory on the homogeneous space (SU(2)/ ≤ft. U(1)\\right){{}× d} with tensorial interaction and gauge invariance under the diagonal action of SU(2). We derive the power counting for arbitrary d. For the case d = 4, we prove perturbative renormalizability to all orders via multi-scale analysis, study both the renormalized and effective perturbation series, and establish the asymptotic freedom of the model. We also outline a general power counting for the homogeneous space {{≤ft(SO(D)/SO(D-1)\\right)}× d} , of direct interest for quantum gravity models in arbitrary dimension, and point out the obstructions to the direct generalization of our results to these cases.
Study of higher order cumulant expansion of U(1) lattice gauge model at finite temperature
International Nuclear Information System (INIS)
Zheng Xite; Lei Chunhong; Li Yuliang; Chen Hong
1993-01-01
The order parameter, Polyakov line , of the U(1) gauge model on N σ 3 x N τ (N τ = 1) lattice by using the cumulant expansion is calculated to the 5-th order. The emphasis is put on the behaviour of the cumulant expansion in the intermediate coupling region. The necessity of higher order expansion is clarified from the connection between the cumulant expansion and the correlation length. The variational parameter in the n-th order calculation is determined by the requirement that corrections of the n-th order expansion to the zeroth order expansion finish. The agreement with the Monte Carlo simulation is obtained not only in the weak and strong coupling regions, but also in the intermediate coupling region except in the very vicinity of the phase transition point
Horizontal, anomalous U(1) symmetry for the more minimal supersymmetric standard model
International Nuclear Information System (INIS)
Nelson, A.E.; Wright, D.
1997-01-01
We construct explicit examples with a horizontal, open-quotes anomalousclose quotes U(1) gauge group, which, in a supersymmetric extension of the standard model, reproduce qualitative features of the fermion spectrum and CKM matrix, and suppress FCNC and proton decay rates without the imposition of global symmetries. We review the motivation for such open-quotes moreclose quotes minimal supersymmetric standard models and their predictions for the sparticle spectrum. There is a mass hierarchy in the scalar sector which is the inverse of the fermion mass hierarchy. We show in detail why ΔS=2 FCNCs are greatly suppressed when compared with naive estimates for nondegenerate squarks. copyright 1997 The American Physical Society
Yeast endoribonuclease stimulated by Novikoff Hepatoma small nuclear RNAS U1 and U2
International Nuclear Information System (INIS)
Stevens, A.
1982-01-01
Using [ 3 H]m 7 Gppp[ 14 C]RNA-poly(A) from yeast as a substrate, an endoribonuclease has been detected in enzyme fractions derived from a high salt wash of ribonucleoprotein particles of Saccharomyces cerevisiae. The [ 3 H]m 7 Gppp[ 14 C]RNA-poly(A) seems to be a preferred substrate since other polyribonucleotides are hydrolyzed more slowly, if at all. The enzyme is inhibited by ethidium bromide, but fully double-stranded polyribonucleotides are not hydrolyzed. The hydrolysis of [ 3 H]m 7 Gppp[ 14 C]RNA-poly(A) is stimulated about 2.5-fold by the addition of small nuclear RNAs U1 and U2 of Novikoff hepatoma cells. Results show that the stimulation involves an interaction of the labeled RNA with the small nuclear RNA
Spitzer DDT observations of the interstellar comet A/2017 U1
Trilling, David; Hora, Joe; Mommert, Michael; Carey, Sean; Lisse, Carey; Werner, Mike; Chesley, Steve; Emery, Josh; Fazio, Giovanni; Fernandez, Yan; Harris, Alan; Marengo, Massimo; Mueller, Migo; Roegge, Alissa; Smith, Howard; Smith, Nathan; Weaver, Hal
2017-11-01
We propose to observe the newly discovered interstellar comet A/2017 U1 to measure its diameter and albedo. Little is known about this object, which presumably formed in another planetary system. This is the only opportunity *ever* to determine the albedo of this object, which will help us understand how planetary system formation in other systems compares to what occurred in our Solar System. The proposed observations -- requiring 32.6 hours in late November -- are the last telescopic observations that will ever be made of this object. The return from these proposed observations would be tremendous -- characterizing the first ever known object from beyond our Solar System. Because the object is faint and fading, these observations must be made as soon as possible.
New approach to high energy SU/sub 2L/ /times/ U1 radiative corrections
International Nuclear Information System (INIS)
Ward, B.F.L.
1988-07-01
We present a new approach to SU/sub 2L/ /times/ U 1 radiative corrections at high energies. Our approach is based on the infrared summation methods of Yennie, Frautschi and Suura, taken together with the Weinberg-'t Hooft renormalization group equation. Specific processes which have been realized via explicit Monte Carlo algorithms are e + e/sup /minus// → f/bar f/' + n(γ), f = μ, /tau/, d, s, u, c, b or t and e + e/sup /minus// → e + e/sup /minus// + n(γ), where n(γ), denotes multiple photo emission on an event-by-event basis. Exemplary Monte Carlo data are presented. 16 refs., 4 figs
The SU(3)xU(1) invariant breaking of gauged N=8 supergravity
International Nuclear Information System (INIS)
Nicolai, H.; Warner, N.P.
1985-01-01
The SU(3) x U(1) invariant stationary point of N=8 supergravity is described in some detail. This vacuum has N=2 supersymmetry, and it is shown how the fields of N=8 supergravity may be collected into multiplets of SU(3) x Osp(2, 4). A new kind of shortened massive multiplet is described, and the multiplet shortening conditions for this and other multiplets are used to determine, by the use of group theory alone, the masses of many of the fields in the vacuum. The remaining masses are determined by explicit calculation. The critical point realizes Gell-Mann's scheme for relating the spin-1/2 fermions of the theory to the observed quarks and leptons. (orig.)
A yeast endoribonuclease stimulated by Novikoff hepatoma small nuclear RNAs U1 and U2
International Nuclear Information System (INIS)
Stevens, A.
1982-01-01
Using [ 3 H]m 7 Gppp[ 14 C]RNA-poly(A) from yeast as a substrate, an endoribonuclease has been detected in enzyme fractions derived from a high salt wash of ribonucleoprotein particles of Saccharomyces cerevisiae. The [ 3 H]m 7 Gppp[ 14 C]RNA-poly(A) seems to be a preferred substrate since other polyribonucleotides are hydrolyzed more slowly, if at all. The enzyme is inhibited by ethidium bromide, but fully double-stranded polyribonucleotides are not hydrolyzed. The hydrolysis of [ 3 H]m 7 Gppp[ 14 C]RNA-poly(A) is stimulated about 2.5-fold by the addition of small nuclear RNAs U1 and U2 of Novikoff hepatoma cells. Results show that the stimulation involves an interaction of the labeled RNA with the small nuclear RNA
Two-color quark matter: U(1)A restoration, superfluidity, and quarkyonic phase
International Nuclear Information System (INIS)
Brauner, Tomas; Fukushima, Kenji; Hidaka, Yoshimasa
2009-01-01
We discuss the phase structure of quantum chromodynamics (QCD) with two colors and two flavors of light quarks. This is motivated by the increasing interest in the QCD phase diagram as follows: (1) The QCD critical point search has been under intensive dispute and its location and existence suffer from uncertainty of effective U(1) A symmetry restoration. (2) A new phase called quarkyonic matter is drawing theoretical and experimental attention but it is not clear whether it can coexist with diquark condensation. We point out that two-color QCD is nontrivial enough to contain essential ingredients for (1) and (2) both, and most importantly, is a system without the sign problem in numerical simulations on the lattice. We adopt the two-flavor Nambu-Jona-Lasinio model extended with the two-color Polyakov loop and make quantitative predictions that can be tested by lattice simulations.
Global analysis of general SU(2) x SU(2) x U(1) models with precision data
Energy Technology Data Exchange (ETDEWEB)
Hsieh, Ken; Yu, Jiang-Hao; Yuan, C.P. [Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Schmitz, Kai [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy
2010-05-15
We present the results of a global analysis of a class of models with an extended electroweak gauge group of the form SU(2) x SU(2) x U(1), often denoted as G(221) models, which include as examples the left-right, the lepto-phobic, the hadro-phobic, the fermio-phobic, the un-unified, and the non-universal models. Using an effective Lagrangian approach, we compute the shifts to the coeffcients in the electroweak Lagrangian due to the new heavy gauge bosons, and obtain the lower bounds on the masses of the Z' and W' bosons. The analysis of the electroweak parameter bounds reveals a consistent pattern of several key observables that are especially sensitive to the effects of new physics and thus dominate the overall shape of the respective parameter contours. (orig.)
Global analysis of general SU(2) x SU(2) x U(1) models with precision data
International Nuclear Information System (INIS)
Hsieh, Ken; Yu, Jiang-Hao; Yuan, C.P.; Schmitz, Kai; Michigan State Univ., East Lansing, MI
2010-05-01
We present the results of a global analysis of a class of models with an extended electroweak gauge group of the form SU(2) x SU(2) x U(1), often denoted as G(221) models, which include as examples the left-right, the lepto-phobic, the hadro-phobic, the fermio-phobic, the un-unified, and the non-universal models. Using an effective Lagrangian approach, we compute the shifts to the coeffcients in the electroweak Lagrangian due to the new heavy gauge bosons, and obtain the lower bounds on the masses of the Z' and W' bosons. The analysis of the electroweak parameter bounds reveals a consistent pattern of several key observables that are especially sensitive to the effects of new physics and thus dominate the overall shape of the respective parameter contours. (orig.)
Hanford facility RCRA permit condition II.U.1 report: mapping of underground piping
Energy Technology Data Exchange (ETDEWEB)
Hays, C.B.
1996-09-27
The purpose of this report is to fulfill Condition Il.U.1. of the Hanford Facility (HF) Resource Conservation and Recovery Act (RCRA) Permit. The HF RCRA Permit, Number WA7890008967, became effective on September 28, 1994 (Ecology 1994). Permit Conditions Il.U. (mapping) and II.V. (marking) of the HF RCRA Permit, Dangerous Waste (OW) Portion, require the mapping and marking of dangerous waste underground pipelines subject to the provisions of the Washington Administrative Code (WAC) Chapter 173-303. Permit Condition Il.U.I. requires the submittal of a report describing the methodology used to generate pipeline maps and to assure their quality. Though not required by the Permit, this report also documents the approach used for the field marking of dangerous waste underground pipelines.
The U(1)-Higgs model: critical behaviour in the confining-Higgs region
International Nuclear Information System (INIS)
Alonso, J.L.; Azcoiti, V.; Campos, I.; Ciria, J.C.; Cruz, A.; Iniguez, D.; Lesmes, F.; Piedrafita, C.; Rivero, A.; Tarancon, A.; Badoni, D.; Fernandez, L.A.; Munoz Sudupe, A.; Ruiz-Lorenzo, J.J.; Gonzalez-Arroyo, A.; Martinez, P.; Pech, J.; Tellez, P.
1993-01-01
We study numerically the critical properties of the U(1)-Higgs lattice model, with fixed Higgs modulus, in the region of small gauge coupling where the Higgs and confining phases merge. We find evidence for a first-order transition line that ends in a second-order point. By means of a rotation in parameter space we introduce thermodynamic magnitudes and critical exponents in close resemblance with simple models that show analogous critical behaviour. The measured data allow us to fit the critical exponents finding values in agreement with the mean-field prediction. The location of the critical point and the slope of the first-order line are accurately measured. (orig.)
The factorized F-matrices for arbitrary U(1)(N-1) integrable vertex models
International Nuclear Information System (INIS)
Martins, M.J.; Pimenta, R.A.; Zuparic, M.
2012-01-01
We discuss the F-matrices associated to the R-matrix of a general N-state vertex model whose statistical configurations encode N-1U(1) symmetries. The factorization condition is shown for arbitrary weights being based only on the unitarity property and the Yang-Baxter relation satisfied by the R-matrix. Focusing on the N=3 case we are able to conjecture the structure of some relevant twisted monodromy matrix elements for general weights. We apply this result providing the algebraic expressions of the domain wall partition functions built up in terms of the creation and annihilation monodromy fields. For N=3 we also exhibit a R-matrix whose weights lie on a del Pezzo surface and have a rather general structure.
Paramagnetic properties of the (U1-xTbx)Co2Ge2 solid solutions
International Nuclear Information System (INIS)
Kuznietz, Moshe; Pinto, Haim; Ettedgui, Hanania
1995-01-01
Polycrystalline (U 1-x Tb x )Co 2 Ge 2 solid solutions have the ThCr 2 Si 2 -type crystal structure and order antiferromagnetically. AC-susceptibility at 80-295 K yields paramagnetic Curie temperatures θ=-350±50, -15±5, -50±15, -12±5, and -80±5 K, and effective magnetic moments μ eff =4.5, 5.9, 7.3, 8.5, and 12.0 (±0.5)μ B , for samples with x=0, 0.25, 0.50, 0.75 and 1, respectively. The high μ eff values are related to occurrence of paramagnetic moments on U, Tb and Co, of which only U and Tb moments order magnetically. ((orig.))
b → s transitions in family-dependent U(1)(prime) models
International Nuclear Information System (INIS)
Barger, V.; Everett, L.; Jiang, J.; Langacker, P.; Liu, T.; Wagner, C.E.M.
2009-01-01
We analyze flavor-changing-neutral-current (FCNC) effects in the b → s transitions that are induced by family non-universal U(1)(prime) gauge symmetries. After systematically developing the necessary formalism, we present a correlated analysis for the ΔB = 1,2 processes. We adopt a model-independent approach in which we only require family-universal charges for the first and second generations and small fermion mixing angles. We analyze the constraints on the resulting parameter space from B s -(bar B) mixing and the time-dependent CP asymmetries of the penguin-dominated B d → (π,φ, η(prime), ρ,ω,f0)K S decays. Our results indicate that the currently observed discrepancies in some of these modes with respect to the Standard Model predictions can be consistently accommodated within this general class of models.
Interstellar Interloper 1I/2017 U1: Observations from the NOT and WIYN Telescopes
Jewitt, David; Luu, Jane; Rajagopal, Jayadev; Kotulla, Ralf; Ridgway, Susan; Liu, Wilson; Augusteijn, Thomas
2017-12-01
We present observations of the interstellar interloper 1I/2017 U1 (’Oumuamua) taken during its 2017 October flyby of Earth. The optical colors B - V = 0.70 ± 0.06, V - R = 0.45 ± 0.05, overlap those of the D-type Jovian Trojan asteroids and are incompatible with the ultrared objects that are abundant in the Kuiper Belt. With a mean absolute magnitude H V = 22.95 and assuming a geometric albedo p V = 0.1, we find an average radius of 55 m. No coma is apparent; we deduce a limit to the dust mass production rate of only ˜2 × 10-4 kg s-1, ruling out the existence of exposed ice covering more than a few m2 of the surface. Volatiles in this body, if they exist, must lie beneath an involatile surface mantle ≳0.5 m thick, perhaps a product of prolonged cosmic-ray processing in the interstellar medium. The light curve range is unusually large at ˜2.0 ± 0.2 mag. Interpreted as a rotational light curve the body has axis ratio ≥ {6.3}-1.1+1.3:1 and semi-axes ˜230 m × 35 m. A ≳6:1 axis ratio is extreme relative to most small solar system asteroids and suggests that albedo variations may additionally contribute to the variability. The light curve is consistent with a two-peaked period ˜8.26 hr, but the period is non-unique as a result of aliasing in the data. Except for its unusually elongated shape, 1I/2017 U1 is a physically unremarkable, sub-kilometer, slightly red, rotating object from another planetary system. The steady-state population of similar, ˜100 m scale interstellar objects inside the orbit of Neptune is ˜104, each with a residence time of ˜10 years.
'L=R' -- $U(1)_R$ Lepton Number at the LHC
Energy Technology Data Exchange (ETDEWEB)
Frugiuele, Claudia [Fermilab; Gregoire, Thomas [Ottawa Carleton Inst. Phys.; Kumar, Piyush [Yale U.; Ponton, Eduardo [ISCAP, New York
2013-05-03
We perform a detailed study of a variety of LHC signals in supersymmetric models where lepton number is promoted to an (approximate) U(1)( )R( ) symmetry. Such a symmetry has interesting implications for naturalness, as well as flavor- and CP-violation, among others. Interestingly, it makes large sneutrino vacuum expectation values phenomenologically viable, so that a slepton doublet can play the role of the down-type Higgs. As a result, (some of) the leptons and neutrinos are incorporated into the chargino and neutralino sectors. This leads to characteristic decay patterns that can be experimentally tested at the LHC. The corresponding collider phenomenology is largely determined by the new approximately conserved quantum number, which is itself closely tied to the presence of “leptonic R-parity violation”. We find rather loose bounds on the first and second generation squarks, arising from a combination of suppressed production rates together with relatively small signal efficiencies of the current searches. Naturalness would indicate that such a framework should be discovered in the near future, perhaps through spectacular signals exhibiting the lepto-quark nature of the third generation squarks. The presence of fully visible decays, in addition to decay chains involving large missing energy (in the form of neutrinos) could give handles to access the details of the spectrum of new particles, if excesses over SM background were to be observed. The scale of neutrino masses is intimately tied to the source of U(1)( )R( ) breaking, thus opening a window into the R-breaking sector through neutrino physics. Further theoretical aspects of the model have been presented in the companion paper [1].
A realisation of q-deformed of U(1)-Kac Moody and Virasoro algebras through the a-bar∞ algebra
International Nuclear Information System (INIS)
El Hassouni, A.; Zakkari, M.
1995-11-01
A representation of one parameter deformation of U(1)-Kac Moody and Virasoro algebras is obtained through the infinite matrix algebra a-bar ∞ . Their central extensions are also investigated. (author). 19 refs
International Nuclear Information System (INIS)
Faraggi, A.E.; Pati, J.C.
1997-12-01
Recently a promising mechanism for supersymmetry breaking that utilizes both an anomalous U(1) gauge symmetry and an effective mass term m ∼ 1TeV of certain relevant fields has been proposed. In this paper we examine whether such a mechanism can emerge in superstring derived free fermionic models. We observe that certain three generation string solutions, though not all, lead to an anomalous U(1) which couples universally to all three families. The advantages of this three-family universality of U(1) A , compared to the two-family case, proposed in earlier works, in yielding squark degeneracy, while avoiding radiative breaking of color and charge, are noted. The root cause of the flavor universality of U(1) A is the cyclic permutation symmetry that characterizes the Z 2 x Z 2 orbifold compactification with standard embedding, realized in the free fermionic models by the NAHE set. It is shown that nonrenormalizable terms which contain hidden-sector condensates, generate the required suppression of the relevant mass term m, compared to the Planck scale. While the D-term of the family universal U(1) A leads to squark degeneracy, those of the family dependent U(1)'s, remarkably enough, are found to vanish for the solutions considered, owing to minimization of the potential
Directory of Open Access Journals (Sweden)
Rafal Goraczniak
2013-01-01
Full Text Available U1 Adaptor is a recently discovered oligonucleotide-based gene-silencing technology with a unique mechanism of action that targets nuclear pre-mRNA processing. U1 Adaptors have two distinct functional domains, both of which must be present on the same oligonucleotide to exert their gene-silencing function. Here, we present the first in vivo use of U1 Adaptors by targeting two different human genes implicated in melanomagenesis, B-cell lymphoma 2 (BCL2 and metabotropic glutamate receptor 1 (GRM1, in a human melanoma cell xenograft mouse model system. Using a newly developed dendrimer delivery system, anti-BCL2 U1 Adaptors were very potent and suppressed tumor growth at doses as low as 34 µg/kg with twice weekly intravenous (iv administration. Anti-GRM1 U1 Adaptors suppressed tumor xenograft growth with similar potency. Mechanism of action was demonstrated by showing target gene suppression in tumors and by observing that negative control U1 Adaptors with just one functional domain show no tumor suppression activity. The anti-BCL2 and anti-GRM1 treatments were equally effective against cell lines harboring either wild-type or a mutant V600E B-RAF allele, the most common mutation in melanoma. Treatment of normal immune-competent mice (C57BL6 indicated no organ toxicity or immune stimulation. These proof-of-concept studies represent an in-depth (over 800 mice in ~108 treatment groups validation that U1 Adaptors are a highly potent gene-silencing therapeutic and open the way for their further development to treat other human diseases.
Large (g-2)$_{\\mu}$ in SU(5) x U(1) supergravity models
López, J L; Wang, X
1994-01-01
We compute the supersymmetric contribution to the anomalous magnetic moment of the muon within the context of $SU(5)\\times U(1)$ supergravity models. The largest possible contributions to $a^{susy}_\\mu$ occur for the largest allowed values of $\\tan\\beta$ and can easily exceed the present experimentally allowed range, even after the LEP lower bounds on the sparticle masses are imposed. Such $\\tan\\beta$ enhancement implies that $a^{susy}_\\mu$ can greatly exceed both the electroweak contribution ($\\approx1.95\\times10^{-9}$) and the present hadronic uncertainty ($\\approx\\pm1.75\\times10^{-9}$). Therefore, the new E821 Brookhaven experiment (with an expected accuracy of $0.4\\times10^{-9}$) should explore a large fraction (if not all) of the parameter space of these models, corresponding to slepton, chargino, and squarks masses as high as 200, 300, and 1000 GeV respectively. Moreover, contrary to popular belief, the $a^{susy}_\\mu$ contribution can have either sign, depending on the sign of the Higgs mixing parameter...
Collective modes of the Nambu--Jona-Lasinio model with an external U(1) gauge field
International Nuclear Information System (INIS)
Klevansky, S.P.; Jaenicke, J.; Lemmer, R.H.
1991-01-01
The effect of external color fields on the collective modes of the SU L (2)xSU R (2) chiral flavor version of the Nambu--Jona-Lasinio model is studied analytically in a U(1) approximation to the gauge fields. We show that the scalar and pseudoscalar modes respond differently to external chromomagnetic and -electric fields. In the former case, in which chiral asymmetry is enhanced, the modes remain well separated and vary slowly with the field, while in the latter case the scalar mode drops rapidly to become degenerate with the pseudoscalar mode in the chiral limit. In this regime, both modes are weakly coupled to quark matter, and the pseudoscalar pion mode in particular survives as a well-defined excitation as it enters the pair continuum. The Goldberger-Treiman relation, which is shown to hold in the presence of external fields, is responsible for this behavior. Chromoelectric and -magnetic polarizabilities are seen to be equal and opposite with absolute values β σ =2.0α s and β π =0.03α s for the scalar and pseudoscalar modes respectively
Study on Surface Structure of U1-yGdyO2-x Using Raman Spectroscopy
International Nuclear Information System (INIS)
Lee, Jeong Mook; Kim, Jan Dee; Youn, Young Sang; Kim, Jong Goo; Ha, Yeong Keong; Kim, Jong Yun
2016-01-01
To understand the structural character of the spent nuclear fuel, rare earth element (REE) doped UO 2±x have been studied as simulated spent fuel. The REE doping effect has influence on the phase stability in U-FP-O system, thermal conductivity and the relevant fuel performance. Raman spectroscopy has been used to investigate surface structure of the nuclear fuel materials, because of its sensitivity, convenience and non-destructive sample preparation. The Raman studies on trivalent-doped UO 2 directly show the defect due to oxygen vacancy that could be created by loss of oxygen for charge compensation. This defect has significant effect on the kinetics of fuel oxidation. In this study, we have been investigated the effect on Gd-doping on the UO 2 structure with Raman spectroscopy to characterize the defect structure of nuclear fuel material. The oxygen deficiencies of pellets were estimated by the relation between the doping concentration and a lattice parameter evaluated from XRD spectra. The Raman spectra of U 1-y GdyO 2-x solid solution pellets show the distorted fluorite structure with defect structure due to oxygen vacancies with increasing Gd contents.
Entanglement entropy in (3+1)-d free U(1) gauge theory
Energy Technology Data Exchange (ETDEWEB)
Soni, Ronak M.; Trivedi, Sandip P. [Department of Theoretical Physics, Tata Institute of Fundamental Research,Colaba, Mumbai, 400005 (India)
2017-02-21
We consider the entanglement entropy for a free U(1) theory in 3+1 dimensions in the extended Hilbert space definition. By taking the continuum limit carefully we obtain a replica trick path integral which calculates this entanglement entropy. The path integral is gauge invariant, with a gauge fixing delta function accompanied by a Faddeev -Popov determinant. For a spherical region it follows that the result for the logarithmic term in the entanglement, which is universal, is given by the a anomaly coefficient. We also consider the extractable part of the entanglement, which corresponds to the number of Bell pairs which can be obtained from entanglement distillation or dilution. For a spherical region we show that the coefficient of the logarithmic term for the extractable part is different from the extended Hilbert space result. We argue that the two results will differ in general, and this difference is accounted for by a massless scalar living on the boundary of the region of interest.
Real-Time Dynamics in U(1 Lattice Gauge Theories with Tensor Networks
Directory of Open Access Journals (Sweden)
T. Pichler
2016-03-01
Full Text Available Tensor network algorithms provide a suitable route for tackling real-time-dependent problems in lattice gauge theories, enabling the investigation of out-of-equilibrium dynamics. We analyze a U(1 lattice gauge theory in (1+1 dimensions in the presence of dynamical matter for different mass and electric-field couplings, a theory akin to quantum electrodynamics in one dimension, which displays string breaking: The confining string between charges can spontaneously break during quench experiments, giving rise to charge-anticharge pairs according to the Schwinger mechanism. We study the real-time spreading of excitations in the system by means of electric-field and particle fluctuations. We determine a dynamical state diagram for string breaking and quantitatively evaluate the time scales for mass production. We also show that the time evolution of the quantum correlations can be detected via bipartite von Neumann entropies, thus demonstrating that the Schwinger mechanism is tightly linked to entanglement spreading. To present a variety of possible applications of this simulation platform, we show how one could follow the real-time scattering processes between mesons and the creation of entanglement during scattering processes. Finally, we test the quality of quantum simulations of these dynamics, quantifying the role of possible imperfections in cold atoms, trapped ions, and superconducting circuit systems. Our results demonstrate how entanglement properties can be used to deepen our understanding of basic phenomena in the real-time dynamics of gauge theories such as string breaking and collisions.
The origin of interstellar asteroidal objects like 1I/2017 U1 'Oumuamua
Zwart, S. Portegies; Torres, S.; Pelupessy, I.; Bédorf, J.; Cai, Maxwell X.
2018-05-01
We study the origin of the interstellar object 1I/2017 U1 'Oumuamua by juxtaposing estimates based on the observations with simulations. We speculate that objects like 'Oumuamua are formed in the debris disc as left over from the star and planet formation process, and subsequently liberated. The liberation process is mediated either by interaction with other stars in the parental star-cluster, by resonant interactions within the planetesimal disc or by the relatively sudden mass loss when the host star becomes a compact object. Integrating 'Oumuamua backward in time in the Galactic potential together with stars from the Gaia-TGAS catalogue we find that about 1.3 Myr ago 'Oumuamua passed the nearby star HIP 17288 within a mean distance of 1.3 pc. By comparing nearby observed L-dwarfs with simulations of the Galaxy we conclude that the kinematics of 'Oumuamua is consistent with relatively young objects of 1.1-1.7 Gyr. We just met 'Oumuamua by chance, and with a derived mean Galactic density of ˜3 × 105 similarly sized objects within 100 au from the Sun or ˜1014 per cubic parsec we expect about 2 to 12 such visitors per year within 1 au from the Sun.
Matter fields near quantum critical point in (2+1)-dimensional U(1) gauge theory
International Nuclear Information System (INIS)
Liu Guozhu; Li Wei; Cheng Geng
2010-01-01
We study chiral phase transition and confinement of matter fields in (2+1)-dimensional U(1) gauge theory of massless Dirac fermions and scalar bosons. The vanishing scalar boson mass, r=0, defines a quantum critical point between the Higgs phase and the Coulomb phase. We consider only the critical point r=0 and the Coulomb phase with r>0. The Dirac fermion acquires a dynamical mass when its flavor is less than certain critical value N f c , which depends quantitatively on the flavor N b and the scalar boson mass r. When N f f c , the matter fields carrying internal gauge charge are all confined if r≠0 but are deconfined at the quantum critical point r=0. The system has distinct low-energy elementary excitations at the critical point r=0 and in the Coulomb phase with r≠0. We calculate the specific heat and susceptibility of the system at r=0 and r≠0, which can help to detect the quantum critical point and to judge whether dynamical fermion mass generation takes place.
Sterile neutrino portal to Dark Matter I: the U(1){sub B−L} case
Energy Technology Data Exchange (ETDEWEB)
Escudero, Miguel; Rius, Nuria [Departamento de Física Teórica and IFIC, Universidad de Valencia-CSIC,C/ Catedrático José Beltrán, 2, E-46980 Paterna (Spain); Sanz, Verónica [Department of Physics and Astronomy, University of Sussex,Falmer Campus, Brighton BN1 9QH (United Kingdom)
2017-02-08
In this paper we explore the possibility that the sterile neutrino and Dark Matter sectors in the Universe have a common origin. We study the consequences of this assumption in the simple case of coupling the dark sector to the Standard Model via a global U(1){sub B−L}, broken down spontaneously by a dark scalar. This dark scalar provides masses to the dark fermions and communicates with the Higgs via a Higgs portal coupling. We find an interesting interplay between Dark Matter annihilation to dark scalars — the CP-even that mixes with the Higgs and the CP-odd which becomes a Goldstone boson, the Majoron — and heavy neutrinos, as well as collider probes via the coupling to the Higgs. Moreover, Dark Matter annihilation into sterile neutrinos and its subsequent decay to gauge bosons and quarks, charged leptons or neutrinos lead to indirect detection signatures which are close to current bounds on the gamma ray flux from the galactic center and dwarf galaxies.
On the renormalizability of noncommutative U(1) gauge theory-an algebraic approach
International Nuclear Information System (INIS)
Vilar, L C Q; Tedesco, D G; Lemes, V E R; Ventura, O S
2010-01-01
We investigate the quantum effects of the nonlocal gauge invariant operator 1/D 2 F μν * 1/D 2 F μν in the noncommutative U(1) action and its consequences to the infrared sector of the theory. Nonlocal operators of such kind were proposed to solve the infrared problem of the noncommutative gauge theories evading the questions on the explicit breaking of the Lorentz invariance. More recently, a first step in the localization of this operator was accomplished by means of the introduction of an extra tensorial matter field, and the first loop analysis was carried out (Blaschke et al (2009 Eur. Phys. J. C 62 433-43)). We will complete this localization avoiding the introduction of new degrees of freedom beyond those of the original action by using only BRST doublets. This will allow us to conduct a complete BRST algebraic study of the renormalizability of the theory, following Zwanziger's method of localization of nonlocal operators in QFT.
Explaining the DAMPE data with scalar dark matter and gauged U(1)Le-Lμ interaction
International Nuclear Information System (INIS)
Cao, Junjie; Feng, Lei; Guo, Xiaofei; Shang, Liangliang; Wang, Fei; Wu, Peiwen; Zu, Lei
2018-01-01
Inspired by the peak structure observed by recent DAMPE experiment in e + e - cosmic-ray spectrum, we consider a scalar dark matter (DM) model with gauged U(1) L e -L μ symmetry, which is the most economical anomaly-free theory to potentially explain the peak by DM annihilation in nearby subhalo. We utilize the process χχ → Z ' Z ' → l anti ll ' anti l ' , where χ, Z ' , l (') denote the scalar DM, the new gauge boson and l (') = e, μ, respectively, to generate the e + e - spectrum. By fitting the predicted spectrum to the experimental data, we obtain the favored DM mass range m χ ≅ 3060 +80 -100 GeV and Δm ≡ m χ - m Z'
Algebraic Bethe ansatz for U(1) invariant integrable models: Compact and non-compact applications
International Nuclear Information System (INIS)
Martins, M.J.; Melo, C.S.
2009-01-01
We apply the algebraic Bethe ansatz developed in our previous paper [C.S. Melo, M.J. Martins, Nucl. Phys. B 806 (2009) 567] to three different families of U(1) integrable vertex models with arbitrary N bond states. These statistical mechanics systems are based on the higher spin representations of the quantum group U q [SU(2)] for both generic and non-generic values of q as well as on the non-compact discrete representation of the SL(2,R) algebra. We present for all these models the explicit expressions for both the on-shell and the off-shell properties associated to the respective transfer matrices eigenvalue problems. The amplitudes governing the vectors not parallel to the Bethe states are shown to factorize in terms of elementary building blocks functions. The results for the non-compact SL(2,R) model are argued to be derived from those obtained for the compact systems by taking suitable N→∞ limits. This permits us to study the properties of the non-compact SL(2,R) model starting from systems with finite degrees of freedom.
Algebraic Bethe ansatz for U(1) invariant integrable models: Compact and non-compact applications
Martins, M. J.; Melo, C. S.
2009-10-01
We apply the algebraic Bethe ansatz developed in our previous paper [C.S. Melo, M.J. Martins, Nucl. Phys. B 806 (2009) 567] to three different families of U(1) integrable vertex models with arbitrary N bond states. These statistical mechanics systems are based on the higher spin representations of the quantum group U[SU(2)] for both generic and non-generic values of q as well as on the non-compact discrete representation of the SL(2,R) algebra. We present for all these models the explicit expressions for both the on-shell and the off-shell properties associated to the respective transfer matrices eigenvalue problems. The amplitudes governing the vectors not parallel to the Bethe states are shown to factorize in terms of elementary building blocks functions. The results for the non-compact SL(2,R) model are argued to be derived from those obtained for the compact systems by taking suitable N→∞ limits. This permits us to study the properties of the non-compact SL(2,R) model starting from systems with finite degrees of freedom.
Sterile neutrino portal to Dark Matter I: the U(1)B−L case
International Nuclear Information System (INIS)
Escudero, Miguel; Rius, Nuria; Sanz, Verónica
2017-01-01
In this paper we explore the possibility that the sterile neutrino and Dark Matter sectors in the Universe have a common origin. We study the consequences of this assumption in the simple case of coupling the dark sector to the Standard Model via a global U(1) B−L , broken down spontaneously by a dark scalar. This dark scalar provides masses to the dark fermions and communicates with the Higgs via a Higgs portal coupling. We find an interesting interplay between Dark Matter annihilation to dark scalars — the CP-even that mixes with the Higgs and the CP-odd which becomes a Goldstone boson, the Majoron — and heavy neutrinos, as well as collider probes via the coupling to the Higgs. Moreover, Dark Matter annihilation into sterile neutrinos and its subsequent decay to gauge bosons and quarks, charged leptons or neutrinos lead to indirect detection signatures which are close to current bounds on the gamma ray flux from the galactic center and dwarf galaxies.
Hamiltonian study of improved U(1) lattice gauge theory in three dimensions
International Nuclear Information System (INIS)
Loan, Mushtaq; Hamer, Chris
2004-01-01
A comprehensive analysis of the Symanzik improved anisotropic three-dimensional U(1) lattice gauge theory in the Hamiltonian limit is made. Monte Carlo techniques are used to obtain numerical results for the static potential, ratio of the renormalized and bare anisotropies, the string tension, lowest glueball masses and the mass ratio. Evidence that rotational symmetry is established more accurately for the Symanzik improved anisotropic action is presented. The discretization errors in the static potential and the renormalization of the bare anisotropy are found to be only a few percent compared to errors of about 20-25 % for the unimproved gauge action. Evidence of scaling in the string tension, antisymmetric mass gap and the mass ratio is observed in the weak coupling region and the behavior is tested against analytic and numerical results obtained in various other Hamiltonian studies of the theory. We find that more accurate determination of the scaling coefficients of the string tension and the antisymmetric mass gap has been achieved, and the agreement with various other Hamiltonian studies of the theory is excellent. The improved action is found to give faster convergence to the continuum limit. Very clear evidence is obtained that in the continuum limit the glueball ratio M S /M A approaches exactly 2, as expected in a theory of free, massive bosons
Entanglement entropy in (3 + 1)-d free U(1) gauge theory
Soni, Ronak M.; Trivedi, Sandip P.
2017-02-01
We consider the entanglement entropy for a free U(1) theory in 3+1 dimensions in the extended Hilbert space definition. By taking the continuum limit carefully we obtain a replica trick path integral which calculates this entanglement entropy. The path integral is gauge invariant, with a gauge fixing delta function accompanied by a Faddeev -Popov determinant. For a spherical region it follows that the result for the logarithmic term in the entanglement, which is universal, is given by the a anomaly coefficient. We also consider the extractable part of the entanglement, which corresponds to the number of Bell pairs which can be obtained from entanglement distillation or dilution. For a spherical region we show that the coefficient of the logarithmic term for the extractable part is different from the extended Hilbert space result. We argue that the two results will differ in general, and this difference is accounted for by a massless scalar living on the boundary of the region of interest.
Gu, Jinbao
2017-12-01
Soil salinity is a significant threat to sustainable agricultural production worldwide. Plants must adjust their developmental and physiological processes to cope with salt stress. Although the capacity for adaptation ultimately depends on the genome, the exceptional versatility in gene regulation provided by the spliceosome-mediated alternative splicing (AS) is essential in these adaptive processes. However, the functions of the spliceosome in plant stress responses are poorly understood. Here, we report the in-depth characterization of a U1 spliceosomal protein, AtU1A, in controlling AS of pre-mRNAs under salt stress and salt stress tolerance in Arabidopsis thaliana. The atu1a mutant was hypersensitive to salt stress and accumulated more reactive oxygen species (ROS) than the wild-type under salt stress. RNA-seq analysis revealed that AtU1A regulates AS of many genes, presumably through modulating recognition of 5′ splice sites. We showed that AtU1A is associated with the pre-mRNA of the ROS detoxification-related gene ACO1 and is necessary for the regulation of ACO1 AS. ACO1 is important for salt tolerance because ectopic expression of ACO1 in the atu1a mutant can partially rescue its salt hypersensitive phenotype. Our findings highlight the critical role of AtU1A as a regulator of pre-mRNA processing and salt tolerance in plants.
Energy Technology Data Exchange (ETDEWEB)
Leontaris, G.K.; Rizos, J.; Tamvakis, K. (Ioannina Univ. (Greece). Theoretical Physics Div.)
1990-06-28
We calculate the trilinear superpotential of the hidden sector of the three generation flipped SU(5)xU(1)xU(1){sup 4}xSO(10)xSU(4) superstring model. We perform a renormalization group analysis of the model taking into account the hidden sector. We find that, in all relevant cases, fractionally charged tetraplets of the hidden SO(6) gauge group are confined at a high scale. Nevertheless, their contribution to the observable U(1) gauge coupling evolution results in a drastic reduction of the available freedom in the values of a{sub 3}(m{sub w}), sin{sup 2}{theta}{sub w} and M{sub x} that allow superunification. (orig.).
International Nuclear Information System (INIS)
Yamaguchi, Masahiro; Yamamoto, Hisashi; Onogi, Tetsuya
1989-01-01
In four-dimensional heterotic string models with anomalous U(1) gauge groups, space-time supersymmetry (SUSY) breaks down spontaneously at one loop. In this paper, the Ward-Takahashi identity of broken SUSY in one-loop two-point amplitudes is investigated in all generalities. The boson-fermion mass splitting of any supersymmetric pair in an arbitrary model is proportional to the product of the D-term expectation value (the sum of (chirality)x(U(1) charge) of massless fermions in the model) and the U(1) charge of the external particle. In order to give a better understanding of the results, we present some examples of the mass splittings in a simple Z 3 orbifold model. (orig.)
TH-A-BRC-01: AAPM TG-135U1 QA for Robotic Radiosurgery
International Nuclear Information System (INIS)
Dieterich, S.
2016-01-01
AAPM TG-135U1 QA for Robotic Radiosurgery - Sonja Dieterich Since the publication of AAPM TG-135 in 2011, the technology of robotic radiosurgery has rapidly developed. AAPM TG-135U1 will provide recommendations on the clinical practice for using the IRIS collimator, fiducial-less real-time motion tracking, and Monte Carlo based treatment planning. In addition, it will summarize currently available literature about uncertainties. Learning Objectives: Understand the progression of technology since the first TG publication Learn which new QA procedures should be implemented for new technologies Be familiar with updates to clinical practice guidelines AAPM TG-178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance - Steven Goetsch Purpose: AAPM Task Group 178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance was formed in August, 2008. The Task Group has 12 medical physicists, two physicians and two consultants. Methods: A round robin dosimetry intercomparison of proposed ionization chambers, electrometer and dosimetry phantoms was conducted over a 15 month period in 2011 and 2012 (Med Phys 42, 11, Nov, 2015). The data obtained at 9 institutions (with ten different Elekta Gamma Knife units) was analyzed by the lead author using several protocols. Results: The most consistent results were obtained using the Elekta ABS 16cm diameter phantom, with the TG-51 protocol modified as recommended by Alfonso et al (Med Phys 35, 11, Nov 2008). A key white paper (Med Phys, in press) sponsored by Elekta Corporation, was used to obtain correction factors for the ionization chambers and phantoms used in this intercomparison. Consistent results were obtained for both Elekta Gamma Knife Model 4C and Gamma Knife Perfexion units as measured with each of two miniature ionization chambers. Conclusion: The full report gives clinical history and background of gamma stereotactic radiosurgery, clinical examples and history, quality assurance recommendations and outline
TH-A-BRC-01: AAPM TG-135U1 QA for Robotic Radiosurgery
Energy Technology Data Exchange (ETDEWEB)
Dieterich, S. [UC Davis Medical Center (United States)
2016-06-15
AAPM TG-135U1 QA for Robotic Radiosurgery - Sonja Dieterich Since the publication of AAPM TG-135 in 2011, the technology of robotic radiosurgery has rapidly developed. AAPM TG-135U1 will provide recommendations on the clinical practice for using the IRIS collimator, fiducial-less real-time motion tracking, and Monte Carlo based treatment planning. In addition, it will summarize currently available literature about uncertainties. Learning Objectives: Understand the progression of technology since the first TG publication Learn which new QA procedures should be implemented for new technologies Be familiar with updates to clinical practice guidelines AAPM TG-178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance - Steven Goetsch Purpose: AAPM Task Group 178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance was formed in August, 2008. The Task Group has 12 medical physicists, two physicians and two consultants. Methods: A round robin dosimetry intercomparison of proposed ionization chambers, electrometer and dosimetry phantoms was conducted over a 15 month period in 2011 and 2012 (Med Phys 42, 11, Nov, 2015). The data obtained at 9 institutions (with ten different Elekta Gamma Knife units) was analyzed by the lead author using several protocols. Results: The most consistent results were obtained using the Elekta ABS 16cm diameter phantom, with the TG-51 protocol modified as recommended by Alfonso et al (Med Phys 35, 11, Nov 2008). A key white paper (Med Phys, in press) sponsored by Elekta Corporation, was used to obtain correction factors for the ionization chambers and phantoms used in this intercomparison. Consistent results were obtained for both Elekta Gamma Knife Model 4C and Gamma Knife Perfexion units as measured with each of two miniature ionization chambers. Conclusion: The full report gives clinical history and background of gamma stereotactic radiosurgery, clinical examples and history, quality assurance recommendations and outline
Investigations on the renormalizability of a non-commutative u(1) gauge theory
International Nuclear Information System (INIS)
Rofner, A.
2009-01-01
standard model is formulated via gauge field theories. It is therefore crucial to find their non-commutative, renormalizable counterparts. Having said this we have already addressed the goal and content of this dissertation, which consists in finding a potentially renormalizable theta-deformed u(1) gauge theory. In a first step, we studied in detail a localized version of a model, which represents an extension of ordinary u(1) gauge theory (formulated on Euclidean space) to the non-commutative setting, and is based on adding a term similar to the one of Gurau et. al., leading to an IR-damped gauge boson propagator. In the course of one-loop calculations, we have shown that it implements additional degrees of freedom and hence modifies the original physical content of the theory. A way out was found by implementing the modification of the IR sector through the introduction of a soft breaking term similar to the approach of Gribov and Zwanziger known from commutative Yang Mills theory. However, when trying to show renormalizability at one-loop level, it turned out that the action does not contain the appropriate terms for absorbing the IR divergences. usually, in such cases one constructs an effective renormalizable action via application of renormalization schemes such as Algebraic Renormalization, which in this case fails, due to the inherent non-locality of the star product. As a consequence, some ideas regarding the applicability and possible extension of traditional renormalization schemes to non-commutative GFTs have been discussed. Finally a new action (the BRSW model) was constructed. It could be shown to be renormalizable to one-loop order. Although a rigorous proof is still missing, we expect it to be a very promising candidate for the first fully renormalizable non-commutative gauge field theory.(author) [de
Matter, dark matter and gravitational waves from a GUT-scale U(1) phase transition
Energy Technology Data Exchange (ETDEWEB)
Domcke, Valerie
2013-09-15
The cosmological realization of the spontaneous breaking of B-L, the difference of baryon and lepton number, can generate the initial conditions for the hot early universe. In particular, we show that entropy, dark matter and a matter-antimatter asymmetry can be produced in accordance with current observations. If B-L is broken at the grand unification scale, F-term hybrid inflation can be realized in the false vacuum of unbroken B-L. The phase transition at the end of inflation, governed by tachyonic preheating, spontaneously breaks the U(1){sub B-L} symmetry and sets the initial conditions for the following perturbative reheating phase. We provide a detailed, time-resolved picture of the reheating process. The competition of cosmic expansion and entropy production leads to an intermediate plateau of constant temperature, which controls both the generated lepton asymmetry and the dark matter abundance. This enables us to establish relations between the neutrino and superparticle mass spectrum, rendering this mechanism testable. Moreover, we calculate the entire gravitational wave spectrum for this setup. This yields a promising possibility to probe cosmological B - L breaking with forthcoming gravitational wave detectors such as eLISA, advanced LIGO and BBO/DECIGO. The largest contribution is obtained from cosmic strings which is, for typical parameter values, at least eight orders of magnitude higher then the contribution from inflation. Finally, we study the possibility of realizing hybrid inflation in a superconformal framework. We find that superconformal D-term inflation is an interesting possibility generically leading to a two-field inflation model, but in its simplest version disfavoured by the recently published Planck data.
Matter, dark matter and gravitational waves from a GUT-scale U(1) phase transition
International Nuclear Information System (INIS)
Domcke, Valerie
2013-09-01
The cosmological realization of the spontaneous breaking of B-L, the difference of baryon and lepton number, can generate the initial conditions for the hot early universe. In particular, we show that entropy, dark matter and a matter-antimatter asymmetry can be produced in accordance with current observations. If B-L is broken at the grand unification scale, F-term hybrid inflation can be realized in the false vacuum of unbroken B-L. The phase transition at the end of inflation, governed by tachyonic preheating, spontaneously breaks the U(1) B-L symmetry and sets the initial conditions for the following perturbative reheating phase. We provide a detailed, time-resolved picture of the reheating process. The competition of cosmic expansion and entropy production leads to an intermediate plateau of constant temperature, which controls both the generated lepton asymmetry and the dark matter abundance. This enables us to establish relations between the neutrino and superparticle mass spectrum, rendering this mechanism testable. Moreover, we calculate the entire gravitational wave spectrum for this setup. This yields a promising possibility to probe cosmological B - L breaking with forthcoming gravitational wave detectors such as eLISA, advanced LIGO and BBO/DECIGO. The largest contribution is obtained from cosmic strings which is, for typical parameter values, at least eight orders of magnitude higher then the contribution from inflation. Finally, we study the possibility of realizing hybrid inflation in a superconformal framework. We find that superconformal D-term inflation is an interesting possibility generically leading to a two-field inflation model, but in its simplest version disfavoured by the recently published Planck data.
Gauge symmetry breaking in the hidden sector of the flipped SU(5)xU(1) superstring model
Energy Technology Data Exchange (ETDEWEB)
Antoniadis, I.; Rizos, J. (Centre de Physique Theorique, Ecole Polytechnique, 91 - Palaiseau (France)); Tamvakis, K. (Theoretical Physics Div., Univ. Ioannina (Greece))
1992-03-26
We analyze the SU(5)xU(1)'xU(1){sup 4}xSO(10)xSU(4) superstring model with a spontaneously broken hidden sector down to SO(7)xSO(5) taking into account non-renormalizable superpotential terms up to eight order. As a result of the hidden sector breaking the 'exotic' states get a mass and the 'observable' spectrum is composed of the standard three families. In addition, Cabibbo mixing arises at sixth order and an improved fermion mass hierarchy emerges. (orig.).
Critical behavior of the compact 3D U(1) theory in the limit of zero spatial coupling
International Nuclear Information System (INIS)
Borisenko, O; Gravina, M; Papa, A
2008-01-01
Critical properties of the compact three-dimensional U(1) lattice gauge theory are explored at finite temperatures on an asymmetric lattice. For vanishing value of the spatial gauge coupling one obtains an effective two-dimensional spin model which describes the interaction between Polyakov loops. We study numerically the effective spin model for N t = 1,4,8 on lattices with spatial extent ranging from L = 64 to 256. Our results indicate that the finite temperature U(1) lattice gauge theory belongs to the universality class of the two-dimensional XY model, thus supporting the Svetitsky–Yaffe conjecture
International Nuclear Information System (INIS)
Heys, D.W.; Stump, D.R.
1987-01-01
Variational calculations are described that use multi-parameter trial wave functions for the U(1) lattice gauge theory in two space dimensions, and for the XY model. The trial functions are constructed as the exponential of a linear combination of states from the strong-coupling basis of the model, with the coefficients treated as variational parameters. The expectation of the hamiltonian is computed by the Monte Carlo method, using a reweighting technique to evaluate expectation values in finite patches of the parameter space. The trial function for the U(1) gauge theory involves six variational parameters, and its weak-coupling behaviour is in reasonable agreement with theoretical expectations. (orig.)
U(1) decoupling, Kleiss-Kuijf and Bern-Carrasco-Johansson relations in N=4 super Yang-Mills
International Nuclear Information System (INIS)
Jia Yin; Huang Rijun; Liu Changyong
2010-01-01
By using the Britto-Cachazo-Feng-Witten recursion relation of N=4 super Yang-Mills theory, we proved the color reflection, U(1) decoupling, Kleiss-Kuijf and Bern-Carrasco-Johansson relations for color-ordered amplitudes of N=4 super Yang-Mills theory. This proof verified the conjectured Bern-Carrasco-Johansson relations of matter fields. The proof depended only on general properties of superamplitudes. We showed also that the color reflection relation and U(1)-decoupling relation are special cases of Kleiss-Kuijf relations.
Energy Technology Data Exchange (ETDEWEB)
Montes T, J.L.; Torres A, C.; Perusquia C, R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)
1992-08-15
The objective of the report is the comparison of the radial distributions of burned in the core among the results of the simulation of the Laguna Verde Central U-1 reactor during the operation of the cycles 1 to 4 and the data of the operation with information provided by the fuel supplier. (Author)
Froggatt-Nielsen meets Mordell-Weil: a phenomenological survey of global F-theory GUTs with U(1)s
International Nuclear Information System (INIS)
Krippendorf, Sven; Schäfer-Nameki, Sakura; Wong, Jin-Mann
2015-01-01
In F-theory, U(1) gauge symmetries are encoded in rational sections, which generate the Mordell-Weil group of the elliptic fibration of the compactification space. Recently the possible U(1) charges for global SU(5) F-theory GUTs with smooth rational sections were classified http://dx.doi.org/10.1007/JHEP09(2015)144. In this paper we utilize this classification to probe global F-theory models for their phenomenological viability. After imposing an exotic-free MSSM spectrum, anomaly cancellation (related to hypercharge flux GUT breaking in the presence of U(1) gauge symmetries), absence of dimension four and five proton decay operators and other R-parity violating couplings, and the presence of at least the third generation top Yukawa coupling, we generate the remaining quark and lepton Yukawa textures by a Froggatt-Nielsen mechanism. In this process we require that the dangerous couplings are forbidden at leading order, and when re-generated by singlet vevs, lie within the experimental bounds. We scan over all possible configurations, and show that only a small class of U(1) charge assignments and matter distributions satisfy all the requirements. The solutions give rise to the exact MSSM spectrum with realistic quark and lepton Yukawa textures, which are consistent with the CKM and PMNS mixing matrices. We also discuss the geometric realization of these models, and provide pointers to the class of elliptic fibrations with good phenomenological properties.
International Nuclear Information System (INIS)
Hoffmann, L.; Leonhardt, T.; Mesref, L.; Ruehl, W.
2001-01-01
We discuss the concept of composite fields in flat CFT as well as in the context of AdS/CFT. Furthermore we show how to represent Green functions using generalized hypergeometric functions and apply these techniques to four-point functions. Finally we prove an identity of U(1) Y symmetry for four-point functions
Hoffmann, L.; Leonhardt, T.; Mesref, L.; Rühl, W.
2001-09-01
We discuss the concept of composite fields in flat CFT as well as in the context of AdS/CFT. Furthermore we show how to represent Green functions using generalized hypergeometric functions and apply these techniques to four-point functions. Finally we prove an identity of U(1)Y symmetry for four-point functions.
Analysis of the 3 and 4 cycles with extensions in the operation of the CNLV U-1
International Nuclear Information System (INIS)
Montes T, J.L.; Torres A, C.; Perusquia C, R.
1992-08-01
The objective of the report is the comparison of the radial distributions of burned in the core among the results of the simulation of the Laguna Verde Central U-1 reactor during the operation of the cycles 1 to 4 and the data of the operation with information provided by the fuel supplier. (Author)
Calculation of the top quark mass in the flipped SU(5)xU(1) superstring model
Energy Technology Data Exchange (ETDEWEB)
Leontaris, G.K.; Rizos, J.; Tamvakis, K. (Ioannina Univ. (Greece). Dept. of Physics)
1990-11-08
We present a complete renormalization group calculation of the top-quark mass in the SU(5)xU(1) superstring model. We solve the coupled renormalization group equations for the gauge and Yukawa couplings in the two-loop approximation and obtain the top-quark mass as a function of two parameters of the model which could be chosen to be ratios of singlet VEVs associated with the surplus (U(1)){sup 4} breaking. We obtain a heavy top-quark with 150 GeV{le}m{sub t}<200 GeV, for most part of the parameter space, while lower values are possible only in a very small extremal region. We also compute the allowed range of unification parameters (M{sub x}, sin{sup 2}{theta}{sub w}, {alpha}{sub 3}(M{sub W})) in the presence of a heavy top-quark. (orig.).
Energy Technology Data Exchange (ETDEWEB)
Kang, Zhaofeng [Korea Institute for Advanced Study, School of Physics, Seoul (Korea, Republic of); Institute of Theoretical Physics, Chinese Academy of Sciences, Key Laboratory of Frontiers in Theoretical Physics, Beijing (China); Li, Jinmian [Institute of Theoretical Physics, Chinese Academy of Sciences, Key Laboratory of Frontiers in Theoretical Physics, Beijing (China); University of Adelaide, ARC Centre of Excellence for Particle Physics at the Terascale and CSSM, Department of Physics, Adelaide, SA (Australia); Li, Tianjun [Institute of Theoretical Physics, Chinese Academy of Sciences, Key Laboratory of Frontiers in Theoretical Physics, Beijing (China); University of Electronic Science and Technology of China, School of Physical Electronics, Chengdu (China); Liu, Tao [University of Alberta, Department of Physics, Edmonton, Alberta (Canada); Yang, Jin Min [Institute of Theoretical Physics, Chinese Academy of Sciences, Key Laboratory of Frontiers in Theoretical Physics, Beijing (China)
2016-05-15
The maximal U(1){sub L} supersymmetric inverse seesaw mechanism (MLSIS) provides a natural way to relate asymmetric darkmatter (ADM)with neutrino physics. In this paper we point out that MLSIS is a natural outcome if one dynamically realizes the inverse seesaw mechanism in the next-to minimal supersymmetric standard model (NMSSM) via the dimension-five operator (N){sup 2}S{sup 2}/M{sub *}, with S the NMSSM singlet developing TeV scale VEV; it slightly violates lepton number due to the suppression by the fundamental scale M{sub *}, thus preserving U(1){sub L} maximally. The resulting sneutrino is a distinguishable ADM candidate, oscillating and favored to have weak scale mass. A fairly large annihilating cross section of such a heavy ADM is available due to the presence of singlet. (orig.)
Semidirect product gauge group [SU(3)cxSU(2)L]xU(1)Y and quantization of hypercharge
International Nuclear Information System (INIS)
Hattori, Chuichiro; Matsunaga, Mamoru; Matsuoka, Takeo
2011-01-01
In the standard model the hypercharges of quarks and leptons are not determined by the gauge group SU(3) c xSU(2) L xU(1) Y alone. We show that, if we choose the semidirect product group [SU(3) c xSU(2) L ]xU(1) Y as its gauge group, the hyperchages are settled to be n/6 mod Z(n=0,1,3,4). In addition, the conditions for gauge-anomaly cancellation give strong constraints. As a result, the ratios of the hypercharges are uniquely determined and the gravitational anomaly is automatically canceled. The standard charge assignment to quarks and leptons can be properly reproduced. For exotic matter fields their hypercharges are also discussed.
SU(n)c x SU(m)L x U(1)N generalizations of the standard model
International Nuclear Information System (INIS)
Pleitez, V.
1993-01-01
Generalizations of the Standard Model which are based on the gauge symmetry SU(n) c x SU(m) L x U(1) N are considered. Although the most interesting possibility occurs when n = 3, it will be considered also the cases n = 4,5, both with m = 3,4. It will also be given possible grand unification scenarios. (author). 18 refs
Some new contributions to neutrinoless double β-decay in an SU(2)xU(1) model
International Nuclear Information System (INIS)
Escobar, C.O.
1982-11-01
An SU(2) x U(1) model having both Dirac and Majorana mass terms for the neutrinos, with an extended Higgs sector without natural flavor conservation is considered. Under these conditions, it is shown that for a certain range of the mass parameters of the model, some new contributions become important for the neutrinoless double β-decay (ββ)oν. (Author) [pt
SU(5)×U(1)X grand unification with minimal seesaw and Z‧-portal dark matter
Okada, Nobuchika; Okada, Satomi; Raut, Digesh
2018-05-01
We propose a grand unified SU (5) × U(1)X model, where the standard SU(5) grand unified theory is supplemented by minimal seesaw and a right-handed neutrino dark matter with an introduction of a global Z2-parity. In the presence of three right-handed neutrinos (RHNs), the model is free from all gauge and mixed-gravitational anomalies. The SU(5) symmetry is broken into the Standard Model (SM) gauge group at MGUT ≃ 4 ×1016GeV in the standard manner, while the U(1)X symmetry breaking occurs at the TeV scale, which generates the TeV-scale mass of the U(1)X gauge boson (Z‧ boson) and the three Majorana RHNs. A unique Z2-odd RHN is stable and serves as the dark matter (DM) in the present Universe, while the remaining two RHNs work to generate the SM neutrino masses through the minimal seesaw. We investigate the Z‧-portal RHN DM scenario in this model context. We find that the constraints from the DM relic abundance, and the Z‧ boson search at the Large Hadron Collider (LHC), and the perturbativity bound on the U(1)X gauge coupling are complementary to narrow down the allowed parameter region in the range of 3.0 ≤mZ‧ [TeV ] ≤ 9.2 for the Z‧ boson mass. The allowed region for mZ‧ ≤ 5TeV will be fully covered by the future LHC experiments. We also briefly discuss the successful implementation of Baryogenesis and cosmological inflation scenarios in the present model.
SU(2) X SU(2) X U(1) basis for symmetric SO(6) representations: matrix elements of the generators
International Nuclear Information System (INIS)
Piepenbring, R.; Silvestre-Brac, B.; Szymanski, Z.
1987-01-01
Matrix elements of the group generators for the symmetric irreducible representations of SO(6) are explicitly calculated in a closed form employing thedecomposition chain SO(6) is contained in SU(2) X SU(2) X U(1) (which is different from the well known Wigner supermultiplet scheme). The relation to the Gel'fand Tsetlin method using SO(6) contained in SO(5) up to ... SO(2) is indicated. An example of a physical application is given
Ma, Ernest; Restrepo, Diego; Zapata, Óscar
2018-01-01
The well-known leptonic U(1) symmetry of the Standard Model (SM) of quarks and leptons is extended to include a number of new fermions and scalars. The resulting theory has an invisible QCD axion (thereby solving the strong CP problem), a candidate for weak-scale dark matter (DM), as well as radiative neutrino masses. A possible key connection is a color-triplet scalar, which may be produced and detected at the Large Hadron Collider.
Phenomenology of the spontaneous C P violation in SU(3)L x U(1)Y electroweak models
International Nuclear Information System (INIS)
Epele, Luis N.; Gomez Dumm, Daniel A.
1994-01-01
This work studies the phenomenological consequence of the spontaneous C P violation in a SU(3) L x U(1) Y model with three Higgs triplets and one sextuplet, which has been recently proposed. Since this C P-violating effects are due to the presence of complex vacuum expectation values in the Higgs sector, our analysis requires a detailed study of the enlarged potential
Dark matter contribution to b → sμ+μ- anomaly in local U(1) Lμ -Lτ model
Baek, Seungwon
2018-06-01
We propose a local U(1) Lμ -Lτ model to explain b → sμ+μ- anomaly observed at the LHCb and Belle experiments. The model also has a natural dark matter candidate N. We introduce SU(2)L-doublet colored scalar q ˜ to mediate b → s transition at one-loop level. The U(1) Lμ -Lτ gauge symmetry is broken spontaneously by the scalar S. All the new particles are charged under U(1) Lμ -Lτ. We can obtain C9μ , NP ∼ - 1 to solve the b → sμ+μ- anomaly and can explain the correct dark matter relic density of the universe, ΩDMh2 ≈ 0.12, simultaneously, while evading constraints from electroweak precision tests, neutrino trident experiments and other quark flavor-changing loop processes such as b → sγ and Bs -B‾s mixing. Our model can be tested by searching for Z‧ and new colored scalar at the LHC and B →K* ν ν ‾ process at Belle-II.
FIMP and muon (g−2) in a U(1){sub L{sub μ−L{sub τ}}} model
Energy Technology Data Exchange (ETDEWEB)
Biswas, Anirban [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211 019 (India); Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094 (India); Choubey, Sandhya [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211 019 (India); Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094 (India); Department of Theoretical Physics, School of Engineering Sciences, KTH Royal Institute of Technology, AlbaNova University Center, 106 91 Stockholm (Sweden); Khan, Sarif [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211 019 (India); Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094 (India)
2017-02-23
The tightening of the constraints on the standard thermal WIMP scenario has forced physicists to propose alternative dark matter (DM) models. One of the most popular alternate explanations of the origin of DM is the non-thermal production of DM via freeze-in. In this scenario the DM never attains thermal equilibrium with the thermal soup because of its feeble coupling strength (∼ 10{sup −12}) with the other particles in the thermal bath and is generally called the Feebly Interacting Massive Particle (FIMP). In this work, we present a gauged U(1){sub L{sub μ−L{sub τ}}} extension of the Standard Model (SM) which has a scalar FIMP DM candidate and can consistently explain the DM relic density bound. In addition, the spontaneous breaking of the U(1){sub L{sub μ−L{sub τ}}} gauge symmetry gives an extra massive neutral gauge boson Z{sub μτ} which can explain the muon (g−2) data through its additional one-loop contribution to the process. Lastly, presence of three right-handed neutrinos enable the model to successfully explain the small neutrino masses via the Type-I seesaw mechanism. The presence of the spontaneously broken U(1){sub L{sub μ−L{sub τ}}} gives a particular structure to the light neutrino mass matrix which can explain the peculiar mixing pattern of the light neutrinos.
Energy Technology Data Exchange (ETDEWEB)
Kim, Jihn E. [Kyung Hee University, Department of Physics, Seoul (Korea, Republic of); Center for Axion and Precision Physics Research (IBS), Daejeon (Korea, Republic of); Kyae, Bumseok [Pusan National University, Department of Physics, Busan (Korea, Republic of); Nam, Soonkeon [Kyung Hee University, Department of Physics, Seoul (Korea, Republic of)
2017-12-15
In string compactifications, frequently the anomalous U(1) gauge symmetry appears which belongs to E{sub 8} x E{sub 8}{sup '} of the heterotic string. This anomalous U(1) gauge boson obtains mass at the compactification scale (∼ 10{sup 18} GeV) by absorbing one pseudoscalar (corresponding to the model-independent axion) from the second rank antisymmetric tensor field B{sub MN}. Below the compactification scale a global symmetry U(1){sub anom} results whose charge Q{sub anom} is the original gauge U(1) charge. This is the most natural global symmetry, realizing the ''invisible'' axion. This global symmetry U(1){sub anom} is suitable for a flavor symmetry. In the simplest compactification model with the flipped SU(5) grand unification, all the low energy parameters are calculated in terms of the vacuum expectation values of the standard model singlets. (orig.)
Kim, Jihn E.; Kyae, Bumseok; Nam, Soonkeon
2017-12-01
In string compactifications, frequently the anomalous U(1) gauge symmetry appears which belongs to E_8 × E_8' of the heterotic string. This anomalous U(1) gauge boson obtains mass at the compactification scale (≈ 10^{18 } {GeV}) by absorbing one pseudoscalar (corresponding to the model-independent axion) from the second rank antisymmetric tensor field B_{MN}. Below the compactification scale a global symmetry U(1)_{anom} results whose charge Q_anom is the original gauge U(1) charge. This is the most natural global symmetry, realizing the "invisible" axion. This global symmetry U(1)_{anom} is suitable for a flavor symmetry. In the simplest compactification model with the flipped SU(5) grand unification, all the low energy parameters are calculated in terms of the vacuum expectation values of the standard model singlets.
Freeze-in production of sterile neutrino dark matter in U(1){sub B−L} model
Energy Technology Data Exchange (ETDEWEB)
Biswas, Anirban; Gupta, Aritra [Harish-Chandra Research Institute,Chhatnag Road, Jhunsi, Allahabad 211 019 (India)
2016-09-27
With the advent of new and more sensitive direct detection experiments, scope for a thermal WIMP explanation of dark matter (DM) has become extremely constricted. The non-observation of thermal WIMP in these experiments has put a strong upper bound on WIMP-nucleon scattering cross section and within a few years it is likely to overlap with the coherent neutrino-nucleon cross section. Hence in all probability, DM may have some non-thermal origin. In this work we explore in detail this possibility of a non-thermal sterile neutrino DM within the framework of U(1){sub B−L} model. The U(1){sub B−L} model on the other hand is a well-motivated and minimal way of extending the standard model so that it can explain the neutrino masses via Type-I see-saw mechanism. We have shown, besides explaining the neutrino mass, it can also accommodate a non-thermal sterile neutrino DM with correct relic density. In contrast with the existing literature, we have found that W{sup ±} decay can also be a dominant production mode of the sterile neutrino DM. To obtain the comoving number density of dark matter, we have solved here a coupled set of Boltzmann equations considering all possible decay as well as annihilation production modes of the sterile neutrino dark matter. The framework developed here though has been done for a U(1){sub B−L} model, can be applied quite generally for any models with an extra neutral gauge boson and a fermionic non-thermal dark matter.
Experimentally verifiable Yang-Mills spin 2 gauge theory of gravity with group U(1) x SU(2)
International Nuclear Information System (INIS)
Peng, H.
1988-01-01
In this work, a Yang-Mills spin 2 gauge theory of gravity is proposed. Based on both the verification of the helicity 2 property of the SU(2) gauge bosons of the theory and the agreement of the theory with most observational and experimental evidence, the authors argues that the theory is truly a gravitational theory. An internal symmetry group, the eigenvalues of its generators are identical with quantum numbers, characterizes the interactions of a given class. The author demonstrates that the 4-momentum P μ of a fermion field generates the U(1) x SU(2) internal symmetry group for gravity, but not the transformation group T 4 . That particles are classified by mass and spin implies that the U(1) x SU(2), instead of the Poincare group, is a symmetry group of gravity. It is shown that the U(1) x SU(2) group represents the time displacement and rotation in ordinary space. Thereby internal space associated with gravity is identical with Minkowski spacetime, so a gauge potential of gravity carries two space-time indices. Then he verifies that the SU(2) gravitational boson has helicity 2. It is this fact, spin from internal spin, that explains alternatively why the gravitational field is the only field which is characterized by spin 2. The Physical meaning of gauge potentials of gravity is determined by comparing theory with the results of experiments, such as the Collella-Overhauser-Werner (COW) experiment and the Newtonian limit, etc. The gauge potentials this must identify with ordinary gravitational potentials
Neutrino masses in the flipped SU(5) x U(1) and the SU(4) x O(4) GUT models
Energy Technology Data Exchange (ETDEWEB)
Ranfone, S.; Papageorgiu, E.
1992-03-01
We classify the different neutrino-mass pattern arising in string-inspired Grand Universal Theory (GUT) and supersymmetric GUT models based on the flipped SU(5)xU(1) and the SU(4)xO(4) gauge groups. Phenomenologically interesting spectra are obtained through the interplay of the two seesaw mechanisms present, with typical neutrino masses {approx}10{sup -3} eV in the supersymmetric GUT models and of order 0.1 - 10 KeV in the ordinary GUTs. (author).
Phenomenology of the hierarchical lepton mass spectrum in the flipped SU(5)xU(1) string model
Energy Technology Data Exchange (ETDEWEB)
Leontaris, G.K.; Nanopoulos, D.V.
1988-09-29
A detailed phenomenological analysis of the lepton mass matrices and their implications in the low energy theory are discussed, within the recently proposed SU(5)xU(1) string model. The unification scale is highly constrained while the Yukawa couplings lie in a natural region. The flavour changing decays ..mu.. -> e..gamma.., ..mu.. -> 3e, ..mu.. -> e are highly suppressed while the depletion in the flux of muon neutrinos reported by the Kamiokande is explained through ..nu../sub ..mu../ reversible ..nu../sub tau/ oscillations.
A minimal spontaneous CP violation model with small neutrino mass and SU(2) x U(1) x Z3 symmetry
International Nuclear Information System (INIS)
Geng, C.Q.; Ng, J.N.
1988-04-01
It is shown that spontaneous CP violation and natural flavor conservation can occur in the SU(2) L x U(1) Y model based on two Higgs doublet and one Higgs singlet fields with a Z 3 discrete symmetry. Physical CP nonconservation is purely due to scalar-pseudoscalar mixings. In order for this to be a major source of CP violation a light spin-O boson of mass less than 10 GeV is required. The see-saw mechanism can be implemented to generate small neutrino masses. The model implies a relatively large electric dipole moment for charged leptons and small value for ε'/ε
International Nuclear Information System (INIS)
Segre, G.; Arthur Weldon, H.
1980-01-01
The general problem of conservation of strangeness and other quark flavors by the exchange of several neutral Higgs mesons is investigated in SU (2)/sub L/ x U (1). We find that the horizontal symmetries necessary to enforce this conservation conflict with the known Cabibbo mixing. In particular, if the quarks form an irreducible representation of the horizontal symmetry, the mixing angles are all trivial (i.e. 0 or π/2); if they form a reducible representation, it is possible to have some nontrivial mixing angles, but only if there are several unmixed generations of quarks with exactly the same relative pattern of masses and mixings
International Nuclear Information System (INIS)
Israel, D.; Pakman, A.; Troost, J.
2004-01-01
We define extended SL(2,R)/U(1) characters which include a sum over winding sectors. By embedding these characters into similarly extended characters of N=2 algebras, we show that they have nice modular transformation properties. We calculate the modular matrices of this simple but non-trivial non-rational conformal field theory explicitly. As a result, we show that discrete SL(2,R) representations mix with continuous SL(2,R) representations under modular transformations in the coset conformal field theory. We comment upon the significance of our results for a general theory of non-rational conformal field theories. (author)
The moduli space of two U(1) instantons on noncommutative $R^4$ and $R^3\\times S^1$
Lee, Kimyeong; Tong, David; Yi, Sangheon
2000-01-01
We employ the ADHM method to derive the moduli space of two instantons in U(1) gauge theory on a noncommutative space. We show by an explicit hyperK\\"ahler quotient construction that the relative metric of the moduli space of two instantons on $R^4$ is the Eguchi-Hanson metric and find a unique threshold bound state. For two instantons on $R^3\\times S^1$, otherwise known as calorons, we give the asymptotic metric and conjecture a completion. We further discuss the relationship of caloron modu...
On a phase transition of a Kosterlitz-thouless-type in the d=4, U(1)-lattice gauge theory
International Nuclear Information System (INIS)
Marchetti, D.H.U.; Perez, J.F.
1986-12-01
The d=4, U(1)-lattice gauge theory with the Villain action may be represented as a locally neutral gas of topological (plaquette) charges which interact via a logarithmically confining potential, is shown. Using this representation a renormalization group analysis to show the existence of a phase transition of the Kosterlitz-Thouless-type was performed. An improved hierarchical version of the model which displays (unlike the usual Migdal-Kadanoff approach) a stable line of gaussian fixed points at low temperatures, which should correspond to the usual deconfining region of these systems is presented. (Author) [pt
Nomura, Takaaki; Okada, Hiroshi
2018-03-01
We propose a Dirac type active neutrino with rank two mass matrix and a Majorana fermion dark matter candidate with an alternative local U(1)_{B-L} extension of neutrinophilic two Higgs doublet model. Our dark matter candidate can be stabilized due to charge assignment under the gauge symmetry without imposing extra discrete Z_2 symmetry and the relic density is obtained from an Z' boson exchanging process. Taking into account collider constraints on the Z' boson mass and coupling, we estimate the relic density.
Pure classical SU(2) Yang-Mills theory with potentials invariant under a U(1) gauge subgroup
International Nuclear Information System (INIS)
Bacry, H.
1978-07-01
The present article is devoted to pure SU(2) classical Yang-Mills theories whose potentials are invariant under a U(1) gauge subgroup. Such potentials are shown to be associated with classical Maxwell-like fields with magnetic sources as 't Hooft's monopole is associated with the Dirac magnetic monopole. Conversely, the authors give Yang-Mills potentials corresponding to some Maxwell-like fields, in particular static magnetic fields with emphasis on those with cylindrical symmetry (including the dipole and other multipoles) and the ephemerons corresponding to an instantaneous magnetic multipole
String completion of an SU(3c⊗SU(3L⊗U(1X electroweak model
Directory of Open Access Journals (Sweden)
Andrea Addazi
2016-08-01
Full Text Available The extended electroweak SU(3c⊗SU(3L⊗U(1X symmetry framework “explaining” the number of fermion families is revisited. While 331-based schemes can not easily be unified within the conventional field theory sense, we show how to do it within an approach based on D-branes and (unoriented open strings, on Calabi–Yau singularities. We show how the theory can be UV-completed in a quiver setup, free of gauge and string anomalies. Lepton and baryon numbers are perturbatively conserved, so neutrinos are Dirac-type, and their lightness results from a novel TeV scale seesaw mechanism. Dynamical violation of baryon number by exotic instantons could induce neutron–antineutron oscillations, with proton decay and other dangerous R-parity violating processes strictly forbidden.
Study of electrical transport properties of (U 1- xY x)RuP 2Si 2
Radha, S.; Park, J.-G.; Roy, S. B.; Coles, B. R.; Nigam, A. K.; McEwen, K. A.
1996-02-01
Electrical resistivity and magnetoresistance ( {δϱ}/{ϱ}) measurements on a series of (U 1- xY x)Ru 2Si 2 (0 ⩽ x ⩽ 0.9) compounds in the temperature range 4.2-300 K and in magnetic fields up to 45 kOe are reported. The resistivity measurements do not show any signature of antiferromagnetism for x > 0.5. The compound URu 2Si 2 exhibits a large, positive ( {δϱ}/{ϱ}) presumably due to destruction of Kondo coherence as well as due to antiferromagnetism. The presence of even 5% Y at U-site weakens the Kondo coherence and reduces the magnetoresistance considerably.
Novel SM-like Higgs decay into displaced heavy neutrino pairs in U(1){sup ′} models
Energy Technology Data Exchange (ETDEWEB)
Accomando, Elena [School of Physics and Astronomy, University of Southampton,Highfield, Southampton SO17 1BJ (United Kingdom); Rose, Luigi Delle; Moretti, Stefano [School of Physics and Astronomy, University of Southampton,Highfield, Southampton SO17 1BJ (United Kingdom); Particle Physics Department, Rutherford Appleton Laboratory,Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Olaiya, Emmanuel; Shepherd-Themistocleous, Claire H. [Particle Physics Department, Rutherford Appleton Laboratory,Chilton, Didcot, Oxon OX11 0QX (United Kingdom)
2017-04-13
We examine the observability of heavy neutrino (ν{sub h}) signatures of a U(1){sup ′} enlarged Standard Model (SM) encompassing three heavy Majorana neutrinos alongside the known light neutrino states at the the Large Hadron Collider (LHC). We show that heavy neutrinos can be rather long-lived particles producing distinctive displaced vertices that can be accessed in the CERN LHC detectors. We concentrate here on the gluon fusion production mechanism gg→H{sub 1,2}→ν{sub h}ν{sub h}, where H{sub 1} is the discovered SM-like Higgs and H{sub 2} is a heavier state, yielding displaced leptons following ν{sub h} decays into weak gauge bosons. Using data collected by the end of the LHC Run 2, these signatures would prove to be accessible with negligibly small background.
Search for OH 18 cm Radio Emission from 1I/2017 U1 with the Green Bank Telescope
Park, Ryan S.; Pisano, D. J.; Lazio, T. Joseph W.; Chodas, Paul W.; Naidu, Shantanu P.
2018-05-01
This paper reports the first OH 18 cm line observation of the first detected interstellar object 1I/2017 U1 (‘Oumuamua) using the Green Bank Telescope. We have observed the OH lines at 1665.402, 1667.359, and 1720.53 MHz frequencies with a spectral resolution of 357 Hz (approximately 0.06 km s‑1). At the time of the observation, ‘Oumuamua was at topocentric distance and velocity of 1.07 au and 63.4 km s‑1, respectively, or at heliocentric distance and velocity of 1.8 au and 39 km s‑1, respectively. Based on a detailed data reduction and an analogy-based inversion, our final results confirm the asteroidal origin of ‘Oumuamua with an upper bound OH production of Q[OH] < 0.17 × 1028 s‑1.
Global analysis of general SU(2)xSU(2)xU(1) models with precision data
International Nuclear Information System (INIS)
Hsieh, Ken; Yu, Jiang-Hao; Yuan, C.-P.; Schmitz, Kai
2010-01-01
We present the results of a global analysis of a class of models with an extended electroweak gauge group of the form SU(2)xSU(2)xU(1), often denoted as G(221) models, which include as examples the left-right, the leptophobic, the hadrophobic, the fermiophobic, the un-unified, and the nonuniversal models. Using an effective Lagrangian approach, we compute the shifts to the coefficients in the electroweak Lagrangian due to the new heavy gauge bosons, and obtain the lower bounds on the masses of the Z ' and W ' bosons. The analysis of the electroweak parameter bounds reveals a consistent pattern of several key observables that are especially sensitive to the effects of new physics and thus dominate the overall shape of the respective parameter contours.
Dimensional reduction of U(1) x SU(2) Chern-Simons bosonization: Application to the t - J model
International Nuclear Information System (INIS)
Marchetti, P.A.
1996-09-01
We perform a dimensional reduction of the U(1) x SU(2) Chern-Simons bosonization and apply it to the t - J model, relevant for high T c superconductors. This procedure yields a decomposition of the electron field into a product of two ''semionic'' fields, i.e. fields obeying Abelian braid statistics with statistics parameter θ = 1/4, one carrying the charge and the other the spin degrees of freedom. A mean field theory is then shown to reproduce correctly the large distance behaviour of the correlation functions of the 1D t - J model at >> J. This result shows that to capture the essential physical properties of the model one needs a specific ''semionic'' form of spin-charge separation. (author). 31 refs
Charge commutation relation approach to composite vector bosons in SU(2)sub(L)xU(1)sub(Y)
International Nuclear Information System (INIS)
Yasue, Masaki; Oneda, Sadao.
1984-09-01
Under the assumption that the local SU(2)sub(L)xU(1)sub(Y) symmetry is a good symmetry for new resonances, we predict that msub(W)msub(W*)=costhetamsub(Z)msub(Z*) where theta represents the mixing angle between neutral gauge bosons and msub(W), msub(Z), msub(W*) and msub(Z*) are the masses of W, Z, W* and Z*, respectively. W* and Z* are the lowest lying spin one resonances, whose pure states belong to a triplet of SU(2)sub(L). Possible SU(2)sub(L)-singlet state is assumed to be much heavier than W* and Z*. Low energy phenomenology of weak interactions indicates msub(W)--costhetamsub(Z), suggesting msub(W*)--msub(Z*). (author)
Palynology of the middle jurassic lower graben sand formation of the U-1 well, Danish Central Trough
Energy Technology Data Exchange (ETDEWEB)
Hoelstad, T.
1986-01-01
Twenty-one sidewall core samples from the lower 56 metres of the Lower Graben Sand Formation in the U-1 well are described with respect to their kerogen content and microflora in order to gain a better understanding of the depositional environment and the age relations. Based on e.g. the inconsistent dinoflagellate cyst occurrences, marginal marine conditions are concluded. The dinoglagellate cyst Pareodinia prolongata, Acanthaulax senta, Scriniodinium crystallinum, Energlynia acollaris, Wanaea thysanota and Hystrichogonyaulax cladophora and the recovered playnomorph assemblage in general permit an age determination as follows: 21 m Collovian undifferentiated, 7.9 latest Middle Callovian - earliest Late Callovian, 6.1 m latest Late Callovian and 21 m latest Late Callovian. - earliest Early Oxfordian.
Phenomenology of the SU(3)cxSU(3)LxU(1)X model with exotic charged leptons
International Nuclear Information System (INIS)
Salazar, Juan C.; Ponce, William A.; Gutierrez, Diego A.
2007-01-01
A phenomenological analysis of the three-family model based on the local gauge group SU(3) c xSU(3) L xU(1) X with exotic charged leptons, is carried out. Instead of using the minimal scalar sector able to break the symmetry in a proper way, we introduce an alternative set of four Higgs scalar triplets, which combined with an anomaly-free discrete symmetry, produce quark and charged lepton mass spectrum without hierarchies in the Yukawa coupling constants. We also embed the structure into a simple gauge group and show some conditions to achieve a low energy gauge coupling unification, avoiding possible conflict with proton decay bounds. By using experimental results from the CERN-LEP, SLAC linear collider, and atomic parity violation data, we update constraints on several parameters of the model
Phenomenology of the SU(3)c x SU(3)L x U(1)X model with right-handed neutrinos
International Nuclear Information System (INIS)
Gutierrez, D.A.; Ponce, W.A.; Sanchez, L.A.
2006-01-01
A phenomenological analysis of the three-family model based on the local gauge group SU(3) c x SU(3) L x U(1) X with right-handed neutrinos is carried out. Instead of using the minimal scalar sector able to break the symmetry in a proper way, we introduce an alternative set of four Higgs scalar triplets, which combined with an anomaly-free discrete symmetry, produces a quark mass spectrum without hierarchies in the Yukawa coupling constants. We also embed the structure into a simple gauge group and show some conditions for achieving a low energy gauge coupling unification, avoiding possible conflict with proton decay bounds. By using experimental results from the CERN-LEP, SLAC linear collider, and atomic parity violation data, we update constraints on several parameters of the model. (orig.)
Developing a Treatment Planning Software Based on TG-43U1 Formalism for Cs-137 LDR Brachytherapy.
Sina, Sedigheh; Faghihi, Reza; Soleimani Meigooni, Ali; Siavashpour, Zahra; Mosleh-Shirazi, Mohammad Amin
2013-08-01
The old Treatment Planning Systems (TPSs) used for intracavitary brachytherapy with Cs-137 Selectron source utilize traditional dose calculation methods, considering each source as a point source. Using such methods introduces significant errors in dose estimation. As of 1995, TG-43 is used as the main dose calculation formalism in treatment TPSs. The purpose of this study is to design and establish a treatment planning software for Cs-137 Solectron brachytherapy source, based on TG-43U1 formalism by applying the effects of the applicator and dummy spacers. Two softwares used for treatment planning of Cs-137 sources in Iran (STPS and PLATO), are based on old formalisms. The purpose of this work is to establish and develop a TPS for Selectron source based on TG-43 formalism. In this planning system, the dosimetry parameters of each pellet in different places inside applicators were obtained by MCNP4c code. Then the dose distribution around every combination of active and inactive pellets was obtained by summing the doses. The accuracy of this algorithm was checked by comparing its results for special combination of active and inactive pellets with MC simulations. Finally, the uncertainty of old dose calculation formalism was investigated by comparing the results of STPS and PLATO softwares with those obtained by the new algorithm. For a typical arrangement of 10 active pellets in the applicator, the percentage difference between doses obtained by the new algorithm at 1cm distance from the tip of the applicator and those obtained by old formalisms is about 30%, while the difference between the results of MCNP and the new algorithm is less than 5%. According to the results, the old dosimetry formalisms, overestimate the dose especially towards the applicator's tip. While the TG-43U1 based software perform the calculations more accurately.
Phenomenology of U(1){sub F} extension of inert-doublet model with exotic scalars and leptons
Energy Technology Data Exchange (ETDEWEB)
Dhargyal, Lobsang [Harish-Chandra Research Institute, HBNI, Allahabad (India)
2018-02-15
In this work we will extend the inert-doublet model (IDM) by adding a new U(1){sub F} gauge symmetry to it, under which, a Z{sub 2} even scalar (φ{sub 2}) and Z{sub 2} odd right handed component of two exotic charged leptons (F{sub eR}, F{sub μR}), are charged. We also add one Z{sub 2} even real scalar (φ{sub 1}) and one complex scalar (φ), three neutral Majorana right handed fermions (N{sub 1}, N{sub 2}, N{sub 3}), two left handed components of the exotic charged leptons (F{sub eL}, F{sub μL}) as well as F{sub τ} are all odd under the Z{sub 2}, all of which are not charged under the U(1){sub F}. With these new particles added to the IDM, we have a model which can give two scalar DM candidates, together they can explain the present DM relic density as well as the muon (g-2) anomaly simultaneously. Also in this model the neutrino masses are generated at one loop level. One of the most peculiar feature of this model is that non-trivial solution to the axial gauge anomaly free conditions lead to the prediction of a stable very heavy partner to the electron (F{sub e}), whose present collider limit (13 TeV LHC) on its mass should be around m{sub F{sub e}} ≥ few TeV. (orig.)
International Nuclear Information System (INIS)
Nakayama, Yu
2008-01-01
We show a calculable example of stable supersymmetry (SUSY) breaking models with O(10) eV gravitino mass based on the combination of D-term gauge mediation and U(1)' mediation. A potential problem of the negative mass squared for the SUSY standard model (SSM) sfermions in the D-term gauge mediation is solved by the contribution from the U(1)' mediation. On the other hand, the splitting between the SSM gauginos and sfermions in the U(1)' mediation is circumvented by the contributions from the D-term gauge mediation. Since the U(1)' mediation does not introduce any new SUSY vacua, we achieve a completely stable model under thermal effects. Our model, therefore, has no cosmological difficulty
Somarelli, J A; Mesa, A; Rodriguez, R; Avellan, R; Martinez, L; Zang, Y J; Greidinger, E L; Herrera, R J
2011-03-01
Systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD) are autoimmune illnesses characterized by the presence of high titers of autoantibodies directed against a wide range of 'self ' antigens. Proteins of the U1 small nuclear ribonucleoprotein particle (U1 snRNP) are among the most immunogenic molecules in patients with SLE and MCTD. The recent release of a crystallized U1 snRNP provides a unique opportunity to evaluate the effects of tertiary and quaternary structures on autoantigenicity within the U1 snRNP. In the present study, an epitope map was created using the U1 snRNP crystal structure. A total of 15 peptides were tested in a cohort of 68 patients with SLE, 29 with MCTD and 26 healthy individuals and mapped onto the U1 snRNP structure. Antigenic sites were detected in a variety of structures and appear to include RNA binding domains, but mostly exclude regions necessary for protein-protein interactions. These data suggest that while some autoantibodies may target U1 snRNP proteins as monomers or apoptosis-induced, protease-digested fragments, others may recognize epitopes on assembled protein subcomplexes of the U1 snRNP. Although nearly all of the peptides are strong predictors of autoimmune illness, none were successful at distinguishing between SLE and MCTD. The antigenicity of some peptides significantly correlated with several clinical symptoms. This investigation implicitly highlights the complexities of autoimmune epitopes, and autoimmune illnesses in general, and demonstrates the variability of antigens in patient populations, all of which contribute to difficult clinical diagnoses.
Upper bounds on Higgs and top quark masses in the flipped SU(5)xU(1) superstring model
Energy Technology Data Exchange (ETDEWEB)
Durand, L.; Lopez, J.L.
1989-02-02
In this letter, we use a simplified method to calculate high-energy unitarity constraints on grand unified broken supersymmetric models. We apply the method to the ''flipped'' SU(5)xU(1) superstring model, obtain the constraints at a grand unified mass scale M/sub G/=4x10/sup 16/ GeV, and then use the renormalization group equations to evolve the constraints to the low-energy mass scale M/sub W/. We find upper bounds on the low-energy superpotential parameters which in turn imply absolute upper bounds on the top quark mass, m/sub t/< or approx.200 GeV, and on the lightest neutral Higgs boson mass, Msub(H/sub 1//sup 0/)< or approx.155 GeV. We also obtain an upper bound on Msub(H/sub 1//sup 0/) as a function of m/sub t/ which shows that for favored values of the ratio of Higgs vacuum expectation values Msub(H/sub 1//sup 0/)< or approx.125 GeV.
Black hole physics from two-dimensional dilaton gravity based on the SL(2,R)/U(1) coset model
International Nuclear Information System (INIS)
Nojiri, S.; Oda, I.
1994-01-01
We analyze the quantum two-dimensional dilaton gravity model, which is described by the SL(2,R)/U(1) gauged Wess-Zumino-Witten model deformed by a (1,1) operator. We show that the curvature singularity does not appear when the central charge c matter of the matter fields is given by 22 matter matter matter ∝δ(x + -x 0 + ), create a kind of wormholes, i.e., causally disconnected regions. Most of the quantum information in past null infinity is lost in future null infinity but the lost information would be carried by the wormholes. We also discuss the problem of defining the mass of quantum black holes. On the basis of the argument by Regge and Teitelboim, we show that the ADM mass measured by the observer who lives in one of the asymptotically flat regions is finite and does not vanish in general. On the other hand, the Bondi mass is ill defined in this model. Instead of the Bondi mass, we consider the mass measured by observers who live in an asymptotically flat region at first. A class of observers finds the mass of the black hole created by a shock wave changes as the observers' proper time goes by, i.e., they observe Hawking radiation. The measured mass vanishes after the infinite proper time and the black hole evaporates completely. Therefore the total Hawking radiation is positive even when N<24
Dark Matter's secret liaisons: phenomenology of a dark U(1) sector with bound states
Energy Technology Data Exchange (ETDEWEB)
Cirelli, Marco; Petraki, Kalliopi; Sala, Filippo [Laboratoire de Physique Théorique et Hautes Energies (LPTHE), UMR 7589 CNRS and UPMC, 4 Place Jussieu, F-75252, Paris (France); Panci, Paolo [CERN Theoretical Physics Department, CERN, Case C01600, CH-1211 Genève (Switzerland); Taoso, Marco, E-mail: marco.cirelli@gmail.com, E-mail: paolo.panci@cern.ch, E-mail: kpetraki@lpthe.jussieu.fr, E-mail: filo.sala@gmail.com, E-mail: m.taoso@csic.es [Instituto de Física Teórica (IFT) UAM/CSIC, calle Nicolás Cabrera 13-15, 28049 Cantoblanco, Madrid (Spain)
2017-05-01
Dark matter (DM) charged under a dark U(1) force appears in many extensions of the Standard Model, and has been invoked to explain anomalies in cosmic-ray data, as well as a self-interacting DM candidate. In this paper, we perform a comprehensive phenomenological analysis of such a model, assuming that the DM abundance arises from the thermal freeze-out of the dark interactions. We include, for the first time, bound-state effects both in the DM production and in the indirect detection signals, and quantify their importance for FERMI, AMS-02, and CMB experiments. We find that DM in the mass range 1 GeV to 100 TeV, annihilating into dark photons of MeV to GeV mass, is in conflict with observations. Instead, DM annihilation into heavier dark photons is viable. We point out that the late decays of multi-GeV dark photons can produce significant entropy and thus dilute the DM density. This can lower considerably the dark coupling needed to obtain the DM abundance, and in turn relax the existing constraints.
Neutrino mixing and R{sub K} anomaly in U(1){sub X} models: a bottom-up approach
Energy Technology Data Exchange (ETDEWEB)
Bhatia, Disha; Chakraborty, Sabyasachi; Dighe, Amol [Tata Institute of Fundamental Research,Mumbai 400005 (India)
2017-03-22
We identify a class of U(1){sub X} models which can explain the R{sub K} anomaly and the neutrino mixing pattern, by using a bottom-up approach. The different X-charges of lepton generations account for the lepton universality violation required to explain R{sub K}. In addition to the three right-handed neutrinos needed for the Type-I seesaw mechanism, these minimal models only introduce an additional doublet Higgs and a singlet scalar. While the former helps in reproducing the quark mixing structure, the latter gives masses to neutrinos and the new gauge boson Z{sup ′}. Our bottom-up approach determines the X-charges of all particles using theoretical consistency and experimental constraints. We find the parameter space allowed by the constraints from neutral meson mixing, rare b→s decays and direct collider searches for Z{sup ′}. Such a Z{sup ′} may be observable at the ongoing run of the Large Hadron Collider with a few hundred fb{sup −1} of integrated luminosity.
An SU(3)xU(1) theory of weak-electromagnetic interactions with charged boson mixing
International Nuclear Information System (INIS)
Singer, M.
1978-01-01
An SU(3)xU(1) gauge theory of weak electromagnetic interactions is proposed in which the charged bosons mix with each other. The model naturally ensures e-μ and quark-lepton universality in couplings, and the charged boson mixing permits an equal number of leptons and quark flavours. There are no new stable leptons. All the fermions are placed in triplets and singlets and the theory is vector-like and hence free of anomalies. In addition one of the charged bosons can have a mass less than 43 GeV. Discrete symmetries and specific choices for Higgs fields are postulated to obtain the appropriate boson and fermion masses. Calculations for the decay of the tau particle, which is described as a heavy electron, are given. Multimuon events are discussed as are neutrino neutral currents. Calculations are also given for testing asymmetries in e-hadron scattering due to weak electron neutral currents along with other phenomenology of the model
Spin Triplet Nematic Pairing Symmetry and Superconducting Double Transition in U1-xThxBe13
Machida, Kazushige
2018-03-01
Motivated by a recent experiment on U1-xThxBe13 with x = 3%, we develop a theory to narrow down the possible pair symmetry to consistently describe the double transition utilizing various theoretical tools, including group theory and Ginzburg-Landau theory. It is explained in terms of the two-dimensional representation Eu with spin triplet. Symmetry breaking causes the degenerate Tc to split into two. The low-temperature phase is identified as the cyclic p wave: d(k) = \\hat{x}kx + ɛ \\hat{y}ky + ɛ 2\\hat{z}kz with ɛ3 = 1, whereas the biaxial nematic phase: d(k) = √{3} (\\hat{x}kx - \\hat{y}ky) is the high-temperature one. This allows us to simultaneously identify the uniaxial nematic phase: d(k) = 2\\hat{z}kz - \\hat{x}kx - \\hat{y}ky for UBe13, which spontaneously breaks the cubic symmetry of the system. Those pair functions are fully consistent with this description and existing data. We comment on the accidental scenario in addition to this degeneracy scenario and the intriguing topological nature hidden in this long-known material.
Explaining the DAMPE data with scalar dark matter and gauged U(1)_{L_e-L_μ } interaction
Cao, Junjie; Feng, Lei; Guo, Xiaofei; Shang, Liangliang; Wang, Fei; Wu, Peiwen; Zu, Lei
2018-03-01
Inspired by the peak structure observed by recent DAMPE experiment in e^+e^- cosmic-ray spectrum, we consider a scalar dark matter (DM) model with gauged U(1)_{L_e-L_μ } symmetry, which is the most economical anomaly-free theory to potentially explain the peak by DM annihilation in nearby subhalo. We utilize the process χ χ → Z^' Z^' → l \\bar{l} l^' \\bar{l}^' , where χ , Z^' , l^{(' )} denote the scalar DM, the new gauge boson and l^{(' )} =e, μ , respectively, to generate the e^+e^- spectrum. By fitting the predicted spectrum to the experimental data, we obtain the favored DM mass range m_χ ˜eq 3060^{+80}_{-100} GeV and Δ m ≡ m_χ - m_{Z^' } ≲ 14 GeV at 68% Confidence Level (C.L.). Furthermore, we determine the parameter space of the model which can explain the peak and meanwhile satisfy the constraints from DM relic abundance, DM direct detection and the collider bounds. We conclude that the model we consider can account for the peak, although there exists a tension with the constraints from the LEP-II bound on m_{Z^' } arising from the cross section measurement of e^+e^- → Z^' *} → e^+ e^-.
Yamamoto, Takuya; Nishigaki, Shinsuke M.
2018-02-01
We compute individual distributions of low-lying eigenvalues of a chiral random matrix ensemble interpolating symplectic and unitary symmetry classes by the Nyström-type method of evaluating the Fredholm Pfaffian and resolvents of the quaternion kernel. The one-parameter family of these distributions is shown to fit excellently the Dirac spectra of SU(2) lattice gauge theory with a constant U(1) background or dynamically fluctuating U(1) gauge field, which weakly breaks the pseudoreality of the unperturbed SU(2) Dirac operator. The observed linear dependence of the crossover parameter with the strength of the U(1) perturbations leads to precise determination of the pseudo-scalar decay constant, as well as the chiral condensate in the effective chiral Lagrangian of the AI class.
Directory of Open Access Journals (Sweden)
J. Buitrago
Full Text Available A new classical 2-spinor approach to U(1 gauge theory is presented in which the usual four-potential vector field is replaced by a symmetric second rank spinor. Following a lagrangian formulation, it is shown that the four-rank spinor representing the Maxwell field tensor has a U(1 local gauge invariance in terms of the electric and magnetic field strengths. When applied to the magnetic field of a monopole, this formulation, via the irreducible representation condition for the gauge group, leads to a quantization condition differing by a factor 2 of the one predicted by Dirac without relying on any kind of singular vector potentials. Finally, the U(1 invariant spinor equations, are applied to electron magnetic resonance which has many applications in the study of materials. Keywords: Weyl 2-spinor lenguage, Dirac equation, Gauge theories, Charge quantization
Ducassou, Lionel; Dhers, Laura; Jonasson, Gabriella; Pietrancosta, Nicolas; Boucher, Jean-Luc; Mansuy, Daniel; André, François
2017-09-01
Human cytochrome P450 2U1 (CYP2U1) is an orphan CYP that exhibits several distinctive characteristics among the 57 human CYPs with a highly conserved sequence in almost all living organisms. We compared its protein sequence with those of the 57 human CYPs and constructed a 3D structure of a full-length CYP2U1 model bound to a POPC membrane. We also performed docking experiments of arachidonic acid (AA) and N-arachidonoylserotonin (AS) in this model. The protein sequence of CYP2U1 displayed two unique characteristics when compared to those of the human CYPs, the presence of a longer N-terminal region upstream of the putative trans-membrane helix (TMH) containing 8 proline residues, and of an insert of about 20 amino acids containing 5 arginine residues between helices A' and A. Its N-terminal part upstream of TMH involved an additional short terminal helix, in a manner similar to what was reported in the crystal structure of Saccharomyces cerevisiae CYP51. Our model also showed a specific interaction between the charged residues of insert AA' and phosphate groups of lipid polar heads, suggesting a possible role of this insert in substrate recruitment. Docking of AA and AS in this model showed these substrates in channel 2ac, with the terminal alkyl chain of AA or the indole ring of AS close to the heme, in agreement with the reported CYP2U1-catalyzed AA and AS hydroxylation regioselectivities. This model should be useful to find new endogenous or exogenous CYP2U1 substrates and to interpret the regioselectivity of their hydroxylation. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.
QCD sum rules of the Laplace transform type for the gluon component of the U(1)sub(A) meson mass
International Nuclear Information System (INIS)
Narison, S.
1981-07-01
We get upper bound of the gluon component of the U(1)sub(A) meson mass using QCD sum rules of the Laplace transform type to the two-point functions associated to the divergence of the U(1)sub(A) current in the chiral limit. For Λ is approximately equal to 70 is approximately 210 MeV and fsub(eta') is approximately equal to (0.5 is approximately 0.7) sqrt 3 fsub(π), we obtain Msub(G) is approximately smaller to (0.6 is approximately 0.85) GeV, which indicates an important gluon contribution to the eta' mass. (author)
International Nuclear Information System (INIS)
Watamura, S.
1983-01-01
Solutions of ten-dimensional Maxwell-Einstein theory and a bosonic part of N = 2, D = 10 supergravity theory are examined. It is shown that there is a solution for which six-dimensional internal space is compactified into CP 2 x S 2 . The gauge symmetry of the effective four-dimensional theory is SU(3) x SU(2) x U(1). The introduction of fermions is also considered. The requirement of consistency in introducing a spinsup(C) structure on CP 2 results in a U(1) charge quantization condition. (orig.)
MISAKI, Y; YAMAMOTO, K; YANAGI, K; MIURA, H; ICHIJO, H; KATO, T; MATO, T; WELLINGWESTER, S; NISHIOKA, K; ITO, K
The mechanism of autoantibody production in autoimmune diseases is not well understood. In the present study we performed the B cell epitope mapping of the U1 small nuclear ribonucleoprotein (snRNP)-C, one of the target molecules of anti-nRNP autoantibody to investigate how B cells respond to the
International Nuclear Information System (INIS)
Hoang Ngoc Long; Nguyen Quynh Lan
2003-05-01
We show that the SU(3) C x SU(3) L x U(1) N (3-3-1) model with right-handed neutrinos can provide candidates for self-interacting dark matter, namely they are the CP-even and odd Higgs bosons. These dark matters are stable without imposing of new symmetry and should be weak-interacting. (author)
Directory of Open Access Journals (Sweden)
Augusto Aguirre
2017-01-01
Full Text Available Objective: To compare the platelet concentration obtained after application of the protocol of plasma rich in growth factors - universal 1 (PRGF-U1 and the protocol of Anitua and Andia (PRP-A for obtaining platelet rich plasma. Material and Method: A descriptive, cross-sectional and comparative study was carried out with a simple random probabilistic sample consisting of 16 patients who attended the Periodontics service of the Unit of Second Specialization in Stomatology of the National University of Trujillo. Five blood samples were obtained from each patient, after applying a health questionnaire to rule out any disease or drug consumption, in order to obtain the baseline platelet concentration and that obtained after PRGF-U1 and PRP-A. To compare the platelet concentrations of the two protocols, Student’s t-test was used considering a significance level of p<0.05. RESULTS: The baseline platelet concentration was 371,250±68,203 platelets/μL, for PRGF-U1 it was 747,875±121,645 platelets/μL and for PRP-A it was 595,000±129,202 platelets/μL. A statistically significant difference (p<0.001 was found between both protocols. Conclusion: The PRGF-U1 protocol yielded a higher platelet concentration compared to the Anitúa and Andía protocol.
Functional analysis of U1-70K interacting SR proteins in pre-mRNA splicing in Arabidopsis
International Nuclear Information System (INIS)
Reddy, A.S.N.
2008-01-01
Proteins of a serine/arginine-rich (SR) family are part of the spliceosome and are implicated in both constitutive and alternative splicing of pre-mRNAs. With the funding from DOE we have been studying alternative of splicing of genes encoding serine/arginine-rich (SR) proteins and the roles of SR proteins that interact with U1-70K in regulating basic and alternative splicing. Alternative splicing of pre-mRNAs of Arabidopsis serine/arginine-rich proteins and its regulation by hormones and stresses: We analyzed the splicing of all 19 Arabidopsis genes in different tissues, during different seedling stages and in response to various hormonal and stress treatments. Remarkably, about 90 different transcripts are produced from 15 SR genes, thereby increasing the transcriptome complexity of SR genes by about five fold. Using the RNA isolated from polysomes we have shown that most of the splice variants are recruited for translation. Alternative splicing of some SR genes is controlled in a developmental and tissue-specific manner (Palusa et al., 2007). Interestingly, among the various hormones and abiotic stresses tested, temperature stress (cold and heat) and ultraviolet light dramatically altered alternative splicing of pre-mRNAs of several SR genes whereas hormones altered the splicing of only two SR genes (Palusa et al., 2007). Localization and dynamics of a novel serine/arginine-rich protein that interacts with U1-70K: We analyzed the intranuclear movement of SR45 fused to GFP by fluorescence recovery after photobleaching (FRAP) and fluorescence loss in photobleaching (FLIP). We demonstrate that the movement of GFP-SR45 is ATP-dependent. Interestingly, inhibition of transcription or phosphorylation slowed the mobility of GFP-SR45 (Ali et al., 2006). Our studies have revealed that the nuclear localization signals are located in arg/ser-rich domains (RS) 1 and 2, whereas the speckle targeting signals are exclusively present in RS2 (Ali et al., 2006). The regulation of
International Nuclear Information System (INIS)
Caisso, Marie
2016-01-01
One of the studied routes to reduce nuclear waste amount, is, after plutonium recycling, americium (Am) heterogeneous transmutation in fast neutron reactors, through the generation of short-lives and inert elements. Am irradiation requires the fabrication of U 1-x Am x O 2±δ pellets and the CRMP (Calcined Resin Microsphere Pelletization) process is currently considered as one the most promising candidate among other fabrication routes. It is based, before pellet sintering, on the compaction of U 1-x Am x O 2±δ oxide microspheres, synthesized through the thermal conversion of ion exchange resin microspheres, loaded with UO 2 2+ and Am 3+ cations. Compared to standard methods using powder metallurgy, CRMP process favours pressing step (easy microsphere flow) while limiting generation of highly radioactive Am-based fine particles. In this context, this PhD work was focused on the exhaustive characterization of CRMP process different steps, from a mechanistic and structural point of view. The cation molecular complex used in the resin was thus determined, highlighting carboxylic bidentate ligand binding around U and Am elements. Thermal conversion was also in-situ followed, and the structures of the different synthesized compounds evidenced and accurately characterized, i.e. (U 1-x Am x ) 3 O 8 et U 1-x Am x O 2±δ . Am substitution in each of them was explained, revealing related distortions around U and Am cations. Finally, sintering of U 1-x Am x O 2±δ microspheres shaped into pellets was studied, showing a two-step densification. This unusual behavior corresponds to multi-scale reorganization into the material during sintering thermal treatment, associated to the presence of nanoparticles in the green pellet that sinter at low temperature. (author) [fr
The Cajal body: a meeting place for spliceosomal snRNPs in the nuclear maze
Czech Academy of Sciences Publication Activity Database
Staněk, David; Neugebauer, K. M.
2006-01-01
Roč. 115, č. 5 (2006), s. 343-354 ISSN 0009-5915 R&D Projects: GA ČR(CZ) GA301/05/0601; GA MŠk(CZ) 1K05009; GA MŠk(CZ) LC535 Grant - others:GA-(DE) Max Planck Society; Deutsche Forschung Gemeinschaft(DE) NE909/1-1 Institutional research plan: CEZ:AV0Z50110509 Keywords : Cajal body * spliceosomal snRNP Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.065, year: 2006
Nuclear bodies in the oocyte nucleus of ground beetles are enriched in snRNPs.
Jaglarz, M K
2001-08-01
Within the oocyte nucleus of many insect species, a variable number of intensely stained spherical bodies occur. These nuclear bodies differ significantly from nucleoli and their precise role in nuclei has not been elucidated yet. I have examined some of the histochemical properties as well as the molecular composition of these structures in a representative of ground (carabid) beetles. I demonstrate, using molecular markers, that the nuclear bodies are composed of small nuclear RNAs and associated proteins, including p80 coilin. Hence, they correspond to Cajal bodies (= coiled bodies) described in somatic cell nuclei as well as oocyte germinal vesicles in plant and animal organisms. It is suggested that Cajal bodies in the carabid germinal vesicle serve as a storage site for splicing factors.
International Nuclear Information System (INIS)
Samiullah, M.
1987-11-01
Some of the relevant mathematics of O(5)xU(1) electro weak gauge theory is briefly sketched. The O(5)xU(1) model is presented. To facilitate the discussion of CP-violation in K-decays the relevant Lagrangian is given in several alternative forms. It is shown that in the CP-violating part of the Lagrangian, by a redefinition of quark phases, the coupling of the CP eigenstates K 1 and K 2 cannot be broken. However, if the Cabibbo angle were not present, the states K 1 and K 2 would decouple and the theory would become CP-invariant. Such a result was also reported by Deshpande et al. working with a different formalism. Relating the mixing parameters θ and φ to the parameters ε 1 and ε 2 it is shown that when ε 1 =ε 2 =ε, ε reduces to the usual CP-violating and CPT conserving parameter. (author). 14 refs
ɛ '/ ɛ anomaly and neutron EDM in SU(2) L × SU(2) R × U(1) B- L model with charge symmetry
Haba, Naoyuki; Umeeda, Hiroyuki; Yamada, Toshifumi
2018-05-01
The Standard Model prediction for ɛ '/ ɛ based on recent lattice QCD results exhibits a tension with the experimental data. We solve this tension through W R + gauge boson exchange in the SU(2) L × SU(2) R × U(1) B- L model with `charge symmetry', whose theoretical motivation is to attribute the chiral structure of the Standard Model to the spontaneous breaking of SU(2) R × U(1) B- L gauge group and charge symmetry. We show that {M_W}{_R}study a correlation between ɛ ' /ɛ and the neutron EDM. We confirm that the model can solve the ɛ ' /ɛ anomaly without conflicting the current bound on the neutron EDM, and further reveal that almost all parameter regions in which the ɛ ' /ɛ anomaly is explained will be covered by future neutron EDM searches, which leads us to anticipate the discovery of the neutron EDM.
Phenomenological analysis of supersymmetric σ-models on coset spaces SO(10)/U(5) and E6/[SO(10)xU(1)
International Nuclear Information System (INIS)
Nyawelo, T.S.
2004-12-01
We discuss some phenomenological aspects of gauged supersymmetric σ-models on homogeneous coset-spaces E 6 /[SO(10)xU(1)] and SO(10)/U(5) which are some of the most interesting for phenomenology. We investigate in detail the vacuum configurations of these models, and study the resulting consequences for supersymmetry breaking and breaking of the internal symmetry. Some supersymmetric minima for both models with gauged full isometry groups E 6 and SO(10) are physically problematic as the Kaehler metric becomes singular ad hence the kinetic terms of the Goldstone boson multiplets vanish. This leads us to introduce recently proposed soft supersymmetry-breaking mass terms which displace the minimum away from the singulax point. A non-singular Kaehler metric breaks the linear subgroup SO(10)xU(1) of the E 6 model spontaneously. The particle spectrum of all these different models is computed. (author)
International Nuclear Information System (INIS)
Desai, B.R.; Xu, G.
1990-01-01
Based on the idea that electromagnetism is responsible for mass differences within isotopic multiplets (e.g., pointlike neutron and proton or u and d quarks), we generalize an SU(2)xU(1) model in a toy field theory of vectors to a supersymmetric model and investigate the finite mass difference within the isotopic doublet. It is found that under soft-supersymmetry breaking, a positive n-p mass difference can be obtained under reasonable assumptions for the parameters involved
The linked units of 5S rDNA and U1 snDNA of razor shells (Mollusca: Bivalvia: Pharidae).
Vierna, J; Jensen, K T; Martínez-Lage, A; González-Tizón, A M
2011-08-01
The linkage between 5S ribosomal DNA and other multigene families has been detected in many eukaryote lineages, but whether it provides any selective advantage remains unclear. In this work, we report the occurrence of linked units of 5S ribosomal DNA (5S rDNA) and U1 small nuclear DNA (U1 snDNA) in 10 razor shell species (Mollusca: Bivalvia: Pharidae) from four different genera. We obtained several clones containing partial or complete repeats of both multigene families in which both types of genes displayed the same orientation. We provide a comprehensive collection of razor shell 5S rDNA clones, both with linked and nonlinked organisation, and the first bivalve U1 snDNA sequences. We predicted the secondary structures and characterised the upstream and downstream conserved elements, including a region at -25 nucleotides from both 5S rDNA and U1 snDNA transcription start sites. The analysis of 5S rDNA showed that some nontranscribed spacers (NTSs) are more closely related to NTSs from other species (and genera) than to NTSs from the species they were retrieved from, suggesting birth-and-death evolution and ancestral polymorphism. Nucleotide conservation within the functional regions suggests the involvement of purifying selection, unequal crossing-overs and gene conversions. Taking into account this and other studies, we discuss the possible mechanisms by which both multigene families could have become linked in the Pharidae lineage. The reason why 5S rDNA is often found linked to other multigene families seems to be the result of stochastic processes within genomes in which its high copy number is determinant.
Pereira, J; Wlazlo, W; Benlliure, J; Casarejos, E; Armbruster, P; Bernas, M; Enqvist, T; Legrain, R; Leray, S; Rejmund, F; Mustapha, B; Schmidt, K.-H; Stéphan, C; Taïeb, J; Tassan-Got, L; Volant, C; Boudard, A; Czajkowski, S; 10.1103/PhysRevC.75.014602
2007-01-01
Fission fragments of 1A GeV 238U nuclei interacting with a deuterium target have been investigatedwith the Fragment Separator (FRS) at GSI (Darmstadt) by measuring their isotopicproduction cross-sections and recoil velocities. The results, along with those obtained recently forspallation-evaporation fragments, provide a comprehensive analysis of the spallation nuclear productionsin the reaction 238U(1A GeV)+d. Details about experiment performance, data reductionand results will be presented.
International Nuclear Information System (INIS)
Baig, M.; Colet, J.
1986-01-01
Using Monte Carlo simulations the SU(2)xU(1) lattice gauge theory has been analyzed, which is equivalent for the Wilson action to a U(2) theory, at space-time dimensionalities from d=3 to 5. It has been shown that there exist first-order phase transitions for both d=4 and d=5. A monopole-condensation mechanism seems to be responsible for these phase transitions. At d=3 no phase transitions have been detected. (orig.)
New approach to SU2LxU1 radiative corrections in e+e- annihilation processes near the Z0 resonance
International Nuclear Information System (INIS)
Jadach, S.; Ward, B.F.L.
1988-08-01
We show explicitly how to proceed in the Monte Carlo simulation of SU 2L xU 1 radiative corrections in order to include multiple soft photon emission on an event by event basis. The method is based on the rigorous theory of summing infrared contributions to the respective cross section by Yennie, Frautschi and Suura. Our method is illustrated on the example of initial state bremsstrahlung. (author). 10 refs, 2 figs
O(5)sub(L)xO(5)sub(R)xU(1)sub(V) electro-weak gauge theory and the neutrino pairing mechanism
International Nuclear Information System (INIS)
Samiullah, M.; Mubarak, A.
1981-08-01
The possibility of using the group O(5)sub(L)xO(5)sub(R)xU(1)sub(V) for unifying the weak and electromagnetic interactions is studied. We are led to an anomaly free theory. Potentially the theory has the advantage of incorporating the previous results. For example, all the results of O(5)sub(L)xU(1) studies are, as a special case, obtainable at low energies. In the process of breaking the symmetry down to Weinberg-Salam theory at the level of SU(2)sub(L)xSU(2)sub(R)xU(1)sub(V), we have employed the neutrino proposed by Mannheim. We have been able to reproduce several of the conventional electroweak aspects such as the parity violation in both the lepton and charged quark sectors, Weinberg mixing pattern in the neutral current sector while keeping the left-handed neutrinos massless. All the salient features of low energy phenomenology are shown to follow. (author)
Neutrino masses in the flipped SU(5)xU(1) and the SU(4)xO(4) GUT models
Energy Technology Data Exchange (ETDEWEB)
Papageorgiu, E.; Ranfone, S. (Rutherford Appleton Lab., Chilton (United Kingdom))
1992-05-21
We classify the different neutrino-mass patterns arising in string-inspired GUT and supersymmetric GUT models based on the flipped SU(5)xU(1) and the SU(4)xO(4) gauge groups. Phenomenologically interesting spectra are obtained through the interplay of the two seesaw mechanisms present, with typical neutrino masses {proportional to}10{sup -3} eV in the supersymmetric GUT models and of order 0.1-10 keV in the ordinary GUTs. (orig.).
Higgs Phase in a Gauge U(1 Non-Linear CP1-Model. Two Species of BPS Vortices and Their Zero Modes
Directory of Open Access Journals (Sweden)
Alberto Alonso-Izquierdo
2016-09-01
Full Text Available In this paper, zero modes of fluctuation are dissected around the two species of BPS vortices existing in the critical Higgs phase, where the scalar and vector meson masses are equal, of a gauged U ( 1 nonlinear CP 1 -model. If 2 π n , n ∈ Z , is the quantized magnetic flux of the two species of BPS vortex solutions, 2 n linearly-independent vortex zero modes for each species are found and described. The existence of two species of moduli spaces of dimension 2 n of these stringy topological defects is thus locally shown.
International Nuclear Information System (INIS)
Espinosa P, G.; Estrada P, C.E.; Nunez C, A.; Amador G, R.
2001-01-01
The computer code ANESLI-1 developed by the CNSNS and UAM-I, has the main goal of making stability analysis of nuclear reactors of the BWR type, more specifically, the reactors of the U1 and U2 of the CNLV. However it can be used for another kind of applications. Its capacity of real time simulator, allows the prediction of operational transients, and conditions of dynamic steady states. ANESLI-1 was developed under a modular scheme, which allows to extend or/and to improve its scope. The lineal stability analysis predicts the instabilities produced by the wave density phenomenon. (Author)
International Nuclear Information System (INIS)
Yamaguchi, A.; Sugamoto, A.
2000-01-01
Applying Genetic Algorithm for the Lattice Gauge Theory is formed to be an effective method to minimize the action of gauge field on a lattice. In 4 dimensions, the critical point and the Wilson loop behaviour of SU(2) lattice gauge theory as well as the phase transition of U(1) theory have been studied. The proper coding methodi has been developed in order to avoid the increase of necessary memory and the overload of calculation for Genetic Algorithm. How hichhikers toward equilibrium appear against kidnappers is clarified
Vacuum expectation values of Higgs scalars in a SU(2)/sub L/ x SU(2)/sub R/ x U(1) gauge model
International Nuclear Information System (INIS)
Kitazoe, T.; Mainland, G.B.; Tanaka, K.
1979-01-01
We determine the vacuum expectation values of the Higgs scalars within the framework of a six-quark SU(2)/sub L/ x SU(2)/sub R/ x U(1) gauge model after the imposition of discrete symmetries that are necessary in order to express the Cabibbo angle in terms of quark mass ratios and phases of the vacuum expectation values. We find both real and complex solutions for the vacuum expectation values depending on the relative values of the parameters in the Higgs potential
Vacuum expectation values of Higgs scalars in a SU(2)/sub L/ X SU(2)/sub R/ X U(1) gauge model
International Nuclear Information System (INIS)
Kitazoe, T.; Mainland, G.B.; Tanaka, K.
1978-01-01
The vacuum expectation values of the Higgs scalars are determined within the framework of a six quark SU(2)/sub L/ x SU(2)/sub R/ x U(1) gauge model after the imposition of discrete symmetrics that are necessary in order to express the Cabibbo angle in terms of quark mass ratios and phases of the vacuum expectation values. Both real and complex solutions are found for the vacuum expectation values depending on the relative values of the parameters in the Higgs potential
Z{sup ′}, Higgses and heavy neutrinos in U(1){sup ′} models: from the LHC to the GUT scale
Energy Technology Data Exchange (ETDEWEB)
Accomando, Elena [School of Physics and Astronomy, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Corianò, Claudio [STAG Research Centre and Mathematical Sciences, University of Southampton,Highfield, Southampton SO17 1BJ (United Kingdom); Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento and INFN-Lecce, Via Arnesano, 73100 Lecce (Italy); Rose, Luigi Delle; Fiaschi, Juri [School of Physics and Astronomy, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Marzo, Carlo [Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento and INFN-Lecce, Via Arnesano, 73100 Lecce (Italy); Moretti, Stefano [School of Physics and Astronomy, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom)
2016-07-18
We study a class of non-exotic minimal U(1){sup ′} extensions of the Standard Model, which includes all scenarios that are anomaly-free with the ordinary fermion content augmented by one Right-Handed neutrino per generation, wherein the new Abelian gauge group is spontaneously broken by the non-zero Vacuum Expectation Value of an additional Higgs singlet field, in turn providing mass to a Z{sup ′} state. By adopting the B−L example, whose results can be recast into those pertaining to the whole aforementioned class, and allowing for both scalar and gauge mixing, we first extract the surviving parameter space in presence of up-to-date theoretical and experimental constraints. Over the corresponding parameter configurations, we then delineate the high energy behaviour of such constructs in terms of their stability and perturbativity. Finally, we highlight key production and decay channels of the new states entering the spectra of this class of models, i.e., heavy neutrinos, a second Higgs state and the Z{sup ′}, which are amenable to experimental investigation at the Large Hadron Collider. We therefore set the stage to establish a direct link between measurements obtainable at the Electro-Weak scale and the dynamics of the underlying model up to those where a Grand Unification Theory embedding a U(1){sup ′} can be realised.
International Nuclear Information System (INIS)
Hoffman, D.W.; Query, C.C.; Golden, B.L.; White, S.W.; Keene, J.D.
1991-01-01
An RNA recognition motif (RRM) of ∼80 amino acids constitutes the core of RNA-binding domains found in a large family of proteins involved in RNA processing. The U1 RNA-binding domain of the A protein component of the human U1 small nuclear ribonucleoprotein (RNP), which encompasses the RRM sequence, was analyzed by using NMR spectroscopy. The domain of the A protein is a highly stable monomer in solution consisting of four antiparallel β-strands and two α-helices. The highly conserved RNP1 and RNP2 consensus sequences, containing residues previously suggested to be involved in nucleic acid binding, are juxtaposed in adjacent β-strands. Conserved aromatic side chains that are critical for RNA binding are clustered on the surface to the molecule adjacent to a variable loop that influences recognition of specific RNA sequences. The secondary structure and topology of the RRM are similar to those of ribosomal proteins L12 and L30, suggesting a distant evolutionary relationship between these two types of RNA-associated proteins
Haghshenas, R.; Sheng, D. N.
2018-05-01
We develop an improved variant of U (1 ) -symmetric infinite projected entangled-pair states (iPEPS) ansatz to investigate the ground-state phase diagram of the spin-1 /2 square J1-J2 Heisenberg model. In order to improve the accuracy of the ansatz, we discuss a simple strategy to select automatically relevant symmetric sectors and also introduce an optimization method to treat second-neighbor interactions more efficiently. We show that variational ground-state energies of the model obtained by the U (1 ) -symmetric iPEPS ansatz (for a fixed bond dimension D ) set a better upper bound, improving previous tensor-network-based results. By studying the finite-D scaling of the magnetically order parameter, we find a Néel phase for J2/J1place at J2c2/J1=0.610 (2 ) to the conventional Stripe phase. We compare our results with earlier DMRG and PEPS studies and suggest future directions for resolving remaining issues.
International Nuclear Information System (INIS)
Rozansky, L.; Saleur, H.
1993-01-01
We carry on (in a self-contained fashion) the study of the Alexander-Conway invariant from the quantum field theory point of view started earlier. We investigate for that purpose various aspects of WZW models on supergroups. We first discuss in details S- and T-matrices for the U(1,1) super WZW model and obtain, for the level k an integer, new finite-dimensional representations of the modular group. These have the remarkable property that some of the S-matrix elements are infinite (we show how to properly handle such divergences). Moreover, typical and atypical representations as well as indecomposable blocks are mixed: Truncation to maximally atypical representations, as advocated in some recent papers, is not consistent. Using our approach, multivariable Alexander invariants for links in S 3 can now be fully computed by surgery. Examples of torus and cable knots are discussed. Consistency with classical results provides independent checks of the solution of the U(1,1) WZW model. The main topological application of this work is the computation of Alexander invariants for 3-manifolds and more generally for links in 3-manifolds. Invariants of 3-manifolds themselves seem to depend trivially on the level k, but still contain interesting topological information. For Seifer manifolds for instance, they essentially coincide with the order (number of elements) of the first homology group. Examples of invariants of links in 3-manifolds are given. They exhibit interesting arithmetic properties. (orig.)
Non linear realizations of SU(2) x U(1) in the MSSM model independent analysis and g - 2 of W bosons
Ferrara, Sergio; Porrati, Massimo; Ferrara, Sergio; Masiero, Antonio; Porrati, Massimo
1993-01-01
We perform a model-independent analysis of the spontaneously broken phase of an $SU(2)\\times U(1)$ supersymmetric gauge theory, by using a non-linear parametrization of the Goldstone sector of the theory. The non-linear variables correspond to an $SL(2,C)$ superfield matrix in terms of which a non-linear Lagrangian can be constructed, and the pattern of supersymmetry breaking investigated. The supersymmetric order parameter is the V.E.V. of the neutral pseudo-Goldstone boson. Some applications of this technique are considered, in relation to the minimal supersymmetric standard model, and to determine the $g-2$ of the $W$-bosons in the limit of large top mass.
AUTHOR|(CDS)2075377; Onel, Yasar
2011-01-01
The three main parts of this thesis demonstrate our current understanding of certain physics but mostly go beyond our understanding and present novel approaches, both technically and physically. The first part concentrates on the scalar mesons and presents search methodology to enable a better understanding of their existence and structures. The second part discusses one step further on beyond the standard model physics searches. Emphasis is given to discriminating factors between the MSSM and the U(1)0 gauge extended models. The last part discusses a specific readout problem in calorimetry together with its solution and presents the digital hadron calorimetry, which will be an essential part of calorimeter systems of future colliders.
International Nuclear Information System (INIS)
Goepfert, M.; Mack, G.
1981-07-01
We study the 3-dimensional pure U(1) lattice gauge theory with Villain action which is related to the 3-dimensional Z-ferro-magnet by an exact duality transformation (and also to a Coulomb system). We show that its string tension α is nonzero for all values of the coupling constant g 2 , and obeys and bound α >= const x msub(D)β -1 for small ag 2 , with β = 4π 2 /g 2 and m 2 sub(D) = (2β/a 3 )esup(-βupsiloncb(0)/2) (a = lattice spacing). A continuum limit a → 0, msub(D) fixed, exists and represents a scalar free field theory of mass msub(D). The string tension αmsub(D) -2 in physical units tends to infinite in this limit. Characteristic differences in the behavior of the model for large and small coupling constant ag 2 are found. Renormalization group aspects are discussed. (orig.)
Simulation of 200-400 MeV/u "1"2C + "1"2C elastic scattering on SHARAQ spectrometer
International Nuclear Information System (INIS)
Yu Lei; Zhang Gaolong; Terashima, S.; Le Xiaoyun; Tanihata, I.
2015-01-01
In order to further obtain the information of three-body force (TBF) from 200-400 MeV/u "1"2C + "1"2C elastic scattering, we plan to perform this experiment on a SHARAQ spectrometer. Based on the experimental condition of the Radioactive Ion Beam Factory (RIBF)-SHARAQ facility, a simulation is given to find a compromise between the better energy and angular resolutions, and higher yield by optimizing the target thickness, beam transport mode, beam intensity and angular step. From the simulation, we found that the beam quality mainly limits the improvements of energy and angular resolutions. A beam tracking system as well as a lateral and angular dispersion-matching technique are adopted to reduce the influence of beam quality. According to the two angular settings of SHARAQ as well as the expected cross sections on the basis of the theoretical model, the energy and angular resolutions, and statistical accuracy are estimated. (authors)
Ahmed, Chaara El Mouez
Nous avons etudie les relations de dispersion et la diffusion des glueballs et des mesons dans le modele U(1)_{2+1} compact. Ce modele a ete souvent utilise comme un simple modele de la chromodynamique quantique (QCD), parce qu'il possede le confinement ainsi que les etats de glueballs. Par contre, sa structure mathematique est beaucoup plus simple que la QCD. Notre methode consiste a diagonaliser l'Hamiltonien de ce modele dans une base appropriee de graphes et sur reseau impulsion, afin de generer les relations de dispersion des glueballs et des mesons. Pour la diffusion, nous avons utilise la methode dependante du temps pour calculer la matrice S et la section efficace de diffusion des glueballs et des mesons. Les divers resultats obtenus semblent etre en accord avec les travaux anterieurs de Hakim, Alessandrini et al., Irving et al., qui eux, utilisent plutot la theorie des perturbations en couplage fort, et travaillent sur un reseau espace-temps.
International Nuclear Information System (INIS)
Safigholi, Habib; Faghihi, Reza; Jashni, Somaye Karimi; Meigooni, Ali S.
2012-01-01
Purpose: The goal of this study is to determine a method for Monte Carlo (MC) characterization of the miniature electronic brachytherapy x-ray sources (MEBXS) and to set dosimetric parameters according to TG-43U1 formalism. TG-43U1 parameters were used to get optimal designs of MEBXS. Parameters that affect the dose distribution such as anode shapes, target thickness, target angles, and electron beam source characteristics were evaluated. Optimized MEBXS designs were obtained and used to determine radial dose functions and 2D anisotropy functions in the electron energy range of 25-80 keV. Methods: Tungsten anode material was considered in two different geometries, hemispherical and conical-hemisphere. These configurations were analyzed by the 4C MC code with several different optimization techniques. The first optimization compared target thickness layers versus electron energy. These optimized thicknesses were compared with published results by Ihsan et al.[Nucl. Instrum. Methods Phys. Res. B 264, 371-377 (2007)]. The second optimization evaluated electron source characteristics by changing the cathode shapes and electron energies. Electron sources studied included; (1) point sources, (2) uniform cylinders, and (3) nonuniform cylindrical shell geometries. The third optimization was used to assess the apex angle of the conical-hemisphere target. The goal of these optimizations was to produce 2D-dose anisotropy functions closer to unity. An overall optimized MEBXS was developed from this analysis. The results obtained from this model were compared to known characteristics of HDR 125 I, LDR 103 Pd, and Xoft Axxent electronic brachytherapy source (XAEBS) [Med. Phys. 33, 4020-4032 (2006)]. Results: The optimized anode thicknesses as a function of electron energy is fitted by the linear equation Y (μm) = 0.0459X (keV)-0.7342. The optimized electron source geometry is obtained for a disk-shaped parallel beam (uniform cylinder) with 0.9 mm radius. The TG-43 distribution
Energy Technology Data Exchange (ETDEWEB)
Safigholi, Habib; Faghihi, Reza; Jashni, Somaye Karimi; Meigooni, Ali S. [Faculty of Engineering, Science and Research Branch, Islamic Azad University, Fars, 73481-13111, Persepolis (Iran, Islamic Republic of); Department of Nuclear Engineering and Radiation Research Center, Shiraz University, 71936-16548, Shiraz (Iran, Islamic Republic of); Shiraz University of Medical Sciences, 71348-14336, Shiraz (Iran, Islamic Republic of); Department of Radiation therapy, Comprehensive Cancer Center of Nevada, 3730 South Eastern Avenue, Las Vegas, Nevada 89169 (United States)
2012-04-15
Purpose: The goal of this study is to determine a method for Monte Carlo (MC) characterization of the miniature electronic brachytherapy x-ray sources (MEBXS) and to set dosimetric parameters according to TG-43U1 formalism. TG-43U1 parameters were used to get optimal designs of MEBXS. Parameters that affect the dose distribution such as anode shapes, target thickness, target angles, and electron beam source characteristics were evaluated. Optimized MEBXS designs were obtained and used to determine radial dose functions and 2D anisotropy functions in the electron energy range of 25-80 keV. Methods: Tungsten anode material was considered in two different geometries, hemispherical and conical-hemisphere. These configurations were analyzed by the 4C MC code with several different optimization techniques. The first optimization compared target thickness layers versus electron energy. These optimized thicknesses were compared with published results by Ihsan et al.[Nucl. Instrum. Methods Phys. Res. B 264, 371-377 (2007)]. The second optimization evaluated electron source characteristics by changing the cathode shapes and electron energies. Electron sources studied included; (1) point sources, (2) uniform cylinders, and (3) nonuniform cylindrical shell geometries. The third optimization was used to assess the apex angle of the conical-hemisphere target. The goal of these optimizations was to produce 2D-dose anisotropy functions closer to unity. An overall optimized MEBXS was developed from this analysis. The results obtained from this model were compared to known characteristics of HDR {sup 125}I, LDR {sup 103}Pd, and Xoft Axxent electronic brachytherapy source (XAEBS) [Med. Phys. 33, 4020-4032 (2006)]. Results: The optimized anode thicknesses as a function of electron energy is fitted by the linear equation Y ({mu}m) = 0.0459X (keV)-0.7342. The optimized electron source geometry is obtained for a disk-shaped parallel beam (uniform cylinder) with 0.9 mm radius. The TG-43
Energy Technology Data Exchange (ETDEWEB)
Espinosa P, G.; Estrada P, C.E. [Universidad Autonoma Metropolitana-Iztapalapa, 09000 Mexico D.F. (Mexico); Nunez C, A.; Amador G, R. [Comision Nacional de Seguridad Nuclear y Salvaguardias, Mexico D.F. (Mexico)
2001-07-01
The computer code ANESLI-1 developed by the CNSNS and UAM-I, has the main goal of making stability analysis of nuclear reactors of the BWR type, more specifically, the reactors of the U1 and U2 of the CNLV. However it can be used for another kind of applications. Its capacity of real time simulator, allows the prediction of operational transients, and conditions of dynamic steady states. ANESLI-1 was developed under a modular scheme, which allows to extend or/and to improve its scope. The lineal stability analysis predicts the instabilities produced by the wave density phenomenon. (Author)
Predictions for the neutrino parameters in the minimal gauged U(1){sub L{sub μ-L{sub τ}}} model
Energy Technology Data Exchange (ETDEWEB)
Asai, Kento; Nagata, Natsumi [University of Tokyo, Department of Physics, Bunkyo-ku, Tokyo (Japan); Hamaguchi, Koichi [University of Tokyo, Department of Physics, Bunkyo-ku, Tokyo (Japan); University of Tokyo, Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU), Kashiwa (Japan)
2017-11-15
We study the structure of the neutrino-mass matrix in the minimal gauged U(1){sub L{sub μ-L{sub τ}}} model, where three right-handed neutrinos are added to the Standard Model in order to obtain non-zero masses for the active neutrinos. Because of the U(1){sub L{sub μ-L{sub τ}}} gauge symmetry, the structure of both Dirac and Majorana mass terms of neutrinos is tightly restricted. In particular, the inverse of the neutrino-mass matrix has zeros in the (μ,μ) and (τ,τ) components, namely, this model offers a symmetric realization of the so-called two-zero-minor structure in the neutrino-mass matrix. Due to these constraints, all the CP phases - the Dirac CP phase δ and the Majorana CP phases α{sub 2} and α{sub 3} - as well as the mass eigenvalues of the light neutrinos m{sub i} are uniquely determined as functions of the neutrino mixing angles θ{sub 12}, θ{sub 23}, and θ{sub 13}, and the squared mass differences Δm{sub 21}{sup 2} and Δm{sub 31}{sup 2}. We find that this model predicts the Dirac CP phase δ to be δ ≅ 1.59π-1.70π (1.54π-1.78π), the sum of the neutrino masses to be sum {sub i}m{sub i} ≅ 0.14-0.22 eV (0.12-0.40 eV), and the effective mass for the neutrinoless double-beta decay to be left angle m{sub ββ} right angle ≅ 0.024-0.055 eV (0.017-0.12 eV) at 1σ (2σ) level, which are totally consistent with the current experimental limits. These predictions can soon be tested in future neutrino experiments. Implications for leptogenesis are also discussed. (orig.)
3.5 keV X-ray line signal from dark matter decay in local U(1){sub B−L} extension of Zee-Babu model
Energy Technology Data Exchange (ETDEWEB)
Baek, Seungwon [School of Physics and Open KIAS Center, KIAS,85 Hoegiro Dongdaemun-gu, Seoul 130-722 (Korea, Republic of)
2015-08-06
We consider a local U(1){sub B−L} extension of Zee-Babu model to explain the recently observed 3.5 keV X-ray line signal. The model has three Standard model (SM)-singlet Dirac fermions with different U(1){sub B−L} charges. A complex scalar field charged under U(1){sub B−L} is introduced to break the U(1){sub B−L} symmetry. After U(1){sub B−L} symmetry breaking a remnant discrete symmetry stabilizes the lightest state of the Dirac fermions, which can be a stable dark matter (DM). The second lightest state, if mass splitting with the stable DM is about 3.5 keV, decays dominantly to the stable DM and 3.5 keV photon through two-loop diagrams, explaining the X-ray line signal. Two-loop suppression of the decay amplitude makes its lifetime much longer than the age of the universe and it can be a decaying DM candidate in large parameter region. We also introduce a real scalar field which is singlet under both the SM and U(1){sub B−L} and can explain the current relic abundance of the Dirac fermionic DMs. If the mixing with the SM Higgs boson is small, it does not contribute to DM direct detection. The main contribution to the scattering of DM off atomic nuclei comes from the exchange of U(1){sub B−L} gauge boson, Z{sup ′}, and is suppressed below current experimental bound when Z{sup ′} mass is heavy (≳10 TeV). If the singlet scalar mass is about 0.1–10 MeV, DM self-interaction can be large enough to solve small scale structure problems in simulations with the cold DM, such as, the core-vs-cusp problem and too-big-to-fail problem.
Bryant, Robert L.
1948-01-01
Based on results of longitudinal trim and tumble tests of a 0.057-scale model of the Chance Vought XF7U-1 airplane, the following conclusions regarding the trim and tumble characteristics of the airplane have been drawn: 1. The airplane will not trim at any unusual or uncontrolled angles of attack. 2. The airplane will not tumble with the center of gravity located forward of 24 percent of the mean aerodynamic chord. When the center of gravity is located at 24 percent of the mean aerodynamic chord and slats are extended and elevators are deflected full up, the airplane may tumble if given an external positive pitching moment. 3. The tumbling motion obtained will be readily terminated by deflecting the elevators full down so as to oppose the rotation. 4. The accelerations encountered during an established tumble may be dangerous to the pilot and, therefore, action should be taken to terminate a tumble immediately upon its inception. 5. Simultaneous opening of two wing-tip parachutes having diameters of 4 feet or larger and having drag coefficients of approximately 0.7 will effectively terminate the tumble. 6. Model results indicate that the pilot will not be struck by the airplane if it becomes necessary to leave the airplane during a tumble. The pilot may require aid from an ejection-seat arrangement.
Energy Technology Data Exchange (ETDEWEB)
Corianò, Claudio [STAG Research Centre and Mathematical Sciences,University of Southampton, Southampton SO17 1BJ (United Kingdom); Dipartimento di Matematica e Fisica “Ennio De Giorgi' ,Università del Salento and INFN - Sezione di Lecce,Via Arnesano, 73100 Lecce (Italy); Rose, Luigi Delle; Marzo, Carlo [Dipartimento di Matematica e Fisica “Ennio De Giorgi' ,Università del Salento and INFN - Sezione di Lecce,Via Arnesano, 73100 Lecce (Italy)
2016-02-19
We present a renormalization group study of the scalar potential in a minimal U(1){sub B−L} extension of the Standard Model involving one extra heavier Higgs and three heavy right-handed neutrinos with family universal B-L charge assignments. We implement a type-I seesaw for the masses of the light neutrinos of the Standard Model. In particular, compared to a previous study, we perform a two-loop extension of the evolution, showing that two-loop effects are essential for the study of the stability of the scalar potential up to the Planck scale. The analysis includes the contribution of the kinetic mixing between the two abelian gauge groups, which is radiatively generated by the evolution, and the one-loop matching conditions at the electroweak scale. By requiring the stability of the potential up to the Planck mass, significant constraints on the masses of the heavy neutrinos, on the gauge couplings and the mixing in the Higgs sector are identified.
International Nuclear Information System (INIS)
Jaramillo, Alejandro; Sanchez, Luis A.
2011-01-01
Extensions of the standard model with gauge symmetry SU(3) c x SU(4) L x U(1) X (3-4-1 extensions) where anomaly cancellation takes place between the fermion families (three-family models) predict the existence of two new heavy neutral gauge bosons which transmit flavor changing neutral currents at tree level. In this work, in the context of a three-family 3-4-1 extension which does not contain particles with exotic electric charges, we study the constraints coming from neutral meson mixing on the parameters of the extension associated to tree-level flavor changing neutral current effects. Taking into account experimental measurements of observables related to K and B meson mixing and including new CP-violating phases, we study the resulting bounds for angles and phases in the mixing matrix for the down-quark sector, as well as the implications of these bounds for the modifications in the amplitudes of the clean rare decays K + →π + νν, K L →π 0 νν, K L →π 0 l + l - (l=e, μ) and B d/s →μ + μ - .
Thermochemistry of rare earth doped uranium oxides LnxU1-xO2-0.5x+y (Ln = La, Y, Nd)
Zhang, Lei; Navrotsky, Alexandra
2015-10-01
Lanthanum, yttrium, and neodymium doped uranium dioxide samples in the fluorite structure have been synthesized, characterized in terms of metal ratio and oxygen content, and their enthalpies of formation measured by high temperature oxide melt solution calorimetry. For oxides doped with 10-50 mol % rare earth (Ln) cations, the formation enthalpies from constituent oxides (LnO1.5, UO2 and UO3 in a reaction not involving oxidation or reduction) become increasingly exothermic with increasing rare earth content, while showing no significant dependence on the varying uranium oxidation state. The oxidation enthalpy of LnxU1-xO2-0.5x+y is similar to that of UO2 to UO3 for all three rare earth doped systems. Though this may suggest that the oxidized uranium in these systems is energetically similar to that in the hexavalent state, thermochemical data alone can not constrain whether the uranium is present as U5+, U6+, or a mixture of oxidation states. The formation enthalpies from elements calculated from the calorimetric data are generally consistent with those from free energy measurements.
Phenomenology of an SU(2)×SU(2)×U(1) model with lepton-flavour non-universality
Energy Technology Data Exchange (ETDEWEB)
Boucenna, Sofiane M. [Laboratori Nazionali di Frascati, INFN,Via Enrico Fermi 40, 100044 Frascati (Italy); Celis, Alejandro [Arnold Sommerfeld Center for Theoretical Physics, Fakultät für Physik,Ludwig-Maximilians-Universität München,Theresienstrasse 37, 80333 München (Germany); Fuentes-Martín, Javier; Vicente, Avelino [Instituto de Física Corpuscular, Universitat de València - CSIC,E-46071 València (Spain); Virto, Javier [Albert Einstein Center for Fundamental Physics,Institute for Theoretical Physics, University of Bern,CH-3012 Bern (Switzerland)
2016-12-14
We investigate a gauge extension of the Standard Model in light of the observed hints of lepton universality violation in b→cℓν and b→sℓ{sup +}ℓ{sup −} decays at BaBar, Belle and LHCb. The model consists of an extended gauge group SU(2){sub 1}×SU(2){sub 2}×U(1){sub Y} which breaks spontaneously around the TeV scale to the electroweak gauge group. Fermion mixing effects with vector-like fermions give rise to potentially large new physics contributions in flavour transitions mediated by W{sup ′} and Z{sup ′} bosons. This model can ease tensions in B-physics data while satisfying stringent bounds from flavour physics, and electroweak precision data. Possible ways to test the proposed new physics scenario with upcoming experimental measurements are discussed. Among other predictions, the ratios R{sub M}=Γ(B→Mμ{sup +}μ{sup −})/Γ(B→Me{sup +}e{sup −}), with M=K{sup ∗},ϕ, are found to be reduced with respect to the Standard Model expectation R{sub M}≃1.
Unitary gauge calculation of K0/sub L/ → μ+μ- in the Weinberg SU(2)'/sub L/ x U(1) gauge theory
International Nuclear Information System (INIS)
Olenick, R.P.
1979-01-01
The rare weak decay K 0 /sub L/ → μ + μ - is calculated in the unitary gauge of the Weinberg SU(2)/sub L/ x U(1) model of weak and electromagnetic interactions. A historical development of gauge theories is presented first; this indicates the need for extension of the hadron symmetry group to SU(4). The GIM mechanism, which extends this group by introducing the charmed quark, is incorporated into Weinberg theory. Explicit calculations of the fourth-order Feynman diagrams representing W + W - , Z 0 , γ, and Higgs scalar intermediate states are performed. Through the technique of dimensional regularization the divergent amplitudes are evaluated, and the calculation is shown to be renormalizable by counterterms generated from the original Lagrangian. The Higgs scalar contribution to the effective Lagrangian is found to be greatly suppressed compared to the W + W - and Z 0 contributions, which are used to estimate the charmed quark mass. Analysis reveals that a charmed quark mass less than or equal to 5 GeV will suppress the decay rate to the experimentally observed value. Concluding remarks are made
Zuluaga, Jorge I.; Sánchez-Hernández, Oscar; Sucerquia, Mario; Ferrín, Ignacio
2018-06-01
With the advent of more and deeper sky surveys, the discovery of interstellar small objects entering into the solar system has been finally possible. In 2017 October 19, using observations of the Pan-STARRS survey, a fast moving object, now officially named 1I/2017 U1 (‘Oumuamua), was discovered in a heliocentric unbound trajectory, suggesting an interstellar origin. Assessing the provenance of interstellar small objects is key for understanding their distribution, spatial density, and the processes responsible for their ejection from planetary systems. However, their peculiar trajectories place a limit on the number of observations available to determine a precise orbit. As a result, when its position is propagated ∼105–106 years backward in time, small errors in orbital elements become large uncertainties in position in the interstellar space. In this paper we present a general method for assigning probabilities to nearby stars of being the parent system of an observed interstellar object. We describe the method in detail and apply it for assessing the origin of ‘Oumuamua. A preliminary list of potential progenitors and their corresponding probabilities is provided. In the future, when further information about the object and/or the nearby stars be refined, the probabilities computed with our method can be updated. We provide all the data and codes we developed for this purpose in the form of an open source C/C++/Python package, iWander, which is publicly available at http://github.com/seap-udea/iWander.
A non-perturbative study of 4d U(1) non-commutative gauge theory - the fate of one-loop instability
International Nuclear Information System (INIS)
Bietenholz, Wolfgang; Nishimura, Jun; Susaki, Yoshiaki; Volkholz, Jan
2006-01-01
Recent perturbative studies show that in 4d non-commutative spaces, the trivial (classically stable) vacuum of gauge theories becomes unstable at the quantum level, unless one introduces sufficiently many fermionic degrees of freedom. This is due to a negative IR-singular term in the one-loop effective potential, which appears as a result of the UV/IR mixing. We study such a system non-perturbatively in the case of pure U(1) gauge theory in four dimensions, where two directions are non-commutative. Monte Carlo simulations are performed after mapping the regularized theory onto a U(N) lattice gauge theory in d = 2. At intermediate coupling strength, we find a phase in which open Wilson lines acquire non-zero vacuum expectation values, which implies the spontaneous breakdown of translational invariance. In this phase, various physical quantities obey clear scaling behaviors in the continuum limit with a fixed non-commutativity parameter θ, which provides evidence for a possible continuum theory. The extent of the dynamically generated space in the non-commutative directions becomes finite in the above limit, and its dependence on θ is evaluated explicitly. We also study the dispersion relation. In the weak coupling symmetric phase, it involves a negative IR-singular term, which is responsible for the observed phase transition. In the broken phase, it reveals the existence of the Nambu-Goldstone mode associated with the spontaneous symmetry breaking
A non-perturbative study of 4d U(1) non-commutative gauge theory — the fate of one-loop instability
Bietenholz, Wolfgang; Nishimura, Jun; Susaki, Yoshiaki; Volkholz, Jan
2006-10-01
Recent perturbative studies show that in 4d non-commutative spaces, the trivial (classically stable) vacuum of gauge theories becomes unstable at the quantum level, unless one introduces sufficiently many fermionic degrees of freedom. This is due to a negative IR-singular term in the one-loop effective potential, which appears as a result of the UV/IR mixing. We study such a system non-perturbatively in the case of pure U(1) gauge theory in four dimensions, where two directions are non-commutative. Monte Carlo simulations are performed after mapping the regularized theory onto a U(N) lattice gauge theory in d = 2. At intermediate coupling strength, we find a phase in which open Wilson lines acquire non-zero vacuum expectation values, which implies the spontaneous breakdown of translational invariance. In this phase, various physical quantities obey clear scaling behaviors in the continuum limit with a fixed non-commutativity parameter θ, which provides evidence for a possible continuum theory. The extent of the dynamically generated space in the non-commutative directions becomes finite in the above limit, and its dependence on θ is evaluated explicitly. We also study the dispersion relation. In the weak coupling symmetric phase, it involves a negative IR-singular term, which is responsible for the observed phase transition. In the broken phase, it reveals the existence of the Nambu-Goldstone mode associated with the spontaneous symmetry breaking.
Directory of Open Access Journals (Sweden)
Naoya Toriu
2018-03-01
Full Text Available We report a 33-year-old Japanese man diagnosed with mixed connective tissue disease (MCTD who developed nephrotic proteinuria. Both speckled antinuclear antibody (ANA and anti-U1 ribonucleoprotein (RNP antibody were positive, but anti-double-stranded DNA (dsDNA antibody and anti-Smith (Sm antibody were negative, while complement levels were normal. Renal biopsy revealed membranous glomerulonephritis (MGN with diffuse thickening of the glomerular basement membrane (GBM plus spike and bubble formation. Immunofluorescence demonstrated granular deposits of IgG and C3 along the GBM. Analysis of IgG subclasses showed predominant deposition of IgG1 and IgG4, unlike typical lupus nephritis in which there is predominant deposition of IgG1, IgG2, IgG3, and C1q. Electron microscopy identified numerous large electron-dense deposits (EDD of various types in the subepithelial region of the GBM, but there were no EDD localized in the mesangium or subendothelium. Based on these findings, MGN was considered to be closely related to MCTD in this patient.
Phase stability, crystal structure and magnetism in (U1-xNbx)2 Ni21B6 and (UyNb1-y)3Ni20B6
Provino, Alessia; Bhattacharya, Amitava; Dhar, Sudesh K.; Pani, Marcella; Gatti, Flavio; Paudyal, Durga; Manfrinetti, Pietro
Ternary phases with composition T2M21X6 and T3M20X6 (T = transition metal; M = 3 d metal; X = B, C, P) are reported to crystallize with the W2Cr21C6-type and Mg3Ni20B6-type, respectively (ternary ordered derivatives of the cubic Cr23C6-type, cF116). They attract interest due to their refractory, mechanical, and peculiar magnetic properties. Literature data on these compounds only concern apparently stoichiometric 2:21:6 and 3:20:6 phases. Often only nominal composition has been reported, with few structural refinements and no measurements of physical properties. Lack of detailed stoichiometry and crystallographic data does not allow sufficient understanding of the crystal chemistry and properties of these compounds. We studied stability, crystal structure and magnetism of (U1-xNbx)2 Ni21B6 and (UyNb1-y)3Ni20B6; stable phases are U2Ni21B6 and Nb3Ni20B6, as also confirmed by theoretical calculations. The two pristine compounds solubilize Nb and U, respectively, up to a given extent. The substitution of U by Nb leads to a structural change from the W2Cr21C6- to the Mg3Ni20B6-type. While U2Ni21B6 is a Pauli paramagnet (itinerant non-magnetic state of U-5 f electrons), in agreement with literature, magnetization data for (UyNb1-y)3 Ni20B6 show itinerant ferromagnetism with TC >300 K.
Energy Technology Data Exchange (ETDEWEB)
Hue, L.T. [Duy Tan University, Institute of Research and Development, Da Nang City (Viet Nam); Vietnam Academy of Science and Technology, Institute of Physics, Hanoi (Viet Nam); Arbuzov, A.B. [Joint Institute for Nuclear Researches, Bogoliubov Laboratory for Theoretical Physics, Dubna (Russian Federation); Ngan, N.T.K. [Cantho University, Department of Physics, Cantho (Viet Nam); Vietnam Academy of Science and Technology, Graduate University of Science and Technology, Hanoi (Viet Nam); Long, H.N. [Ton Duc Thang University, Theoretical Particle Physics and Cosmology Research Group, Ho Chi Minh City (Viet Nam); Ton Duc Thang University, Faculty of Applied Sciences, Ho Chi Minh City (Viet Nam)
2017-05-15
The neutrino and Higgs sectors in the SU(2){sub 1} x SU(2){sub 2} x U(1){sub Y} model with lepton-flavor non-universality are discussed. We show that active neutrinos can get Majorana masses from radiative corrections, after adding only new singly charged Higgs bosons. The mechanism for the generation of neutrino masses is the same as in the Zee models. This also gives a hint to solving the dark matter problem based on similar ways discussed recently in many radiative neutrino mass models with dark matter. Except the active neutrinos, the appearance of singly charged Higgs bosons and dark matter does not affect significantly the physical spectrum of all particles in the original model. We indicate this point by investigating the Higgs sector in both cases before and after singly charged scalars are added into it. Many interesting properties of physical Higgs bosons, which were not shown previously, are explored. In particular, the mass matrices of charged and CP-odd Higgs fields are proportional to the coefficient of triple Higgs coupling μ. The mass eigenstates and eigenvalues in the CP-even Higgs sector are also presented. All couplings of the SM-like Higgs boson to normal fermions and gauge bosons are different from the SM predictions by a factor c{sub h}, which must satisfy the recent global fit of experimental data, namely 0.995 < vertical stroke c{sub h} vertical stroke < 1. We have analyzed a more general diagonalization of gauge boson mass matrices, then we show that the ratio of the tangents of the W-W{sup '} and Z-Z{sup '} mixing angles is exactly the cosine of the Weinberg angle, implying that number of parameters is reduced by 1. Signals of new physics from decays of new heavy fermions and Higgs bosons at LHC and constraints of their masses are also discussed. (orig.)
D-term contributions and CEDM constraints in E6 × SU(2)F × U(1)A SUSY GUT model
Shigekami, Yoshihiro
2017-11-01
We focus on E6 × SU(2)F × U(1)A supersymmetric (SUSY) grand unified theory (GUT) model. In this model, realistic Yukawa hierarchies and mixings are realized by introducing all allowed interactions with 𝓞(1) coefficients. Moreover, we can take stop mass is smaller than the other sfermion masses. This type of spectrum called by natural SUSY type sfermion mass spectrum can suppress the SUSY contributions to flavor changing neutral current (FCNC) and stabilize weak scale at the same time. However, light stop predicts large up quark CEDM and stop contributions are not decoupled. Since there is Kobayashi-Maskawa phase, stop contributions to the up quark CEDM is severely constrained even if all SUSY breaking parameters and Higgsino mass parameter μ are real. In this model, real up Yukawa couplings are realized at the GUT scale because of spontaneous CP violation. Therefore CEDM bounds are satisfied, although up Yukawa couplings are complex at the SUSY scale through the renormalization equation group effects. We calculated the CEDMs and found that EDM constraints can be satisfied even if stop mass is 𝓞(1) TeV. In addition, we investigate the size of D-terms in this model. Since these D-term contributions is flavor dependent, the degeneracy of sfermion mass spectrum is destroyed and the size of D-term is strongly constrained by FCNCs when SUSY breaking scale is the weak scale. However, SUSY breaking scale is larger than 1 TeV in order to obtain 125 GeV Higgs mass, and therefore sizable D-term contribution is allowed. Furthermore, we obtained the non-trivial prediction for the difference of squared sfermion mass.
Hue, L. T.; Arbuzov, A. B.; Ngan, N. T. K.; Long, H. N.
2017-05-01
The neutrino and Higgs sectors in the { SU(2) }_1 × { SU(2) }_2 × { U(1) }_Y model with lepton-flavor non-universality are discussed. We show that active neutrinos can get Majorana masses from radiative corrections, after adding only new singly charged Higgs bosons. The mechanism for the generation of neutrino masses is the same as in the Zee models. This also gives a hint to solving the dark matter problem based on similar ways discussed recently in many radiative neutrino mass models with dark matter. Except the active neutrinos, the appearance of singly charged Higgs bosons and dark matter does not affect significantly the physical spectrum of all particles in the original model. We indicate this point by investigating the Higgs sector in both cases before and after singly charged scalars are added into it. Many interesting properties of physical Higgs bosons, which were not shown previously, are explored. In particular, the mass matrices of charged and CP-odd Higgs fields are proportional to the coefficient of triple Higgs coupling μ . The mass eigenstates and eigenvalues in the CP-even Higgs sector are also presented. All couplings of the SM-like Higgs boson to normal fermions and gauge bosons are different from the SM predictions by a factor c_h, which must satisfy the recent global fit of experimental data, namely 0.995<|c_h|<1. We have analyzed a more general diagonalization of gauge boson mass matrices, then we show that the ratio of the tangents of the W-W' and Z-Z' mixing angles is exactly the cosine of the Weinberg angle, implying that number of parameters is reduced by 1. Signals of new physics from decays of new heavy fermions and Higgs bosons at LHC and constraints of their masses are also discussed.
International Nuclear Information System (INIS)
Montes T, J.L.; Cortes C, C.C.
1991-07-01
This work is to carry out a multicycle study for the Laguna Verde U-1 reactor with the FCS-II (1 - 20 cycles) and PRESTO (1 - 6 cycles) codes and to compare the obtained results against those reported by General Electric. (Author)
Energy Technology Data Exchange (ETDEWEB)
Montes T, J L; Cortes C, C C
1991-07-15
This work is to carry out a multicycle study for the Laguna Verde U-1 reactor with the FCS-II (1 - 20 cycles) and PRESTO (1 - 6 cycles) codes and to compare the obtained results against those reported by General Electric. (Author)
Lynn, Bryan W.; Starkman, Glenn D.
2017-09-01
The weak-scale U (1 )Y Abelian Higgs model (AHM) is the simplest spontaneous symmetry breaking (SSB) gauge theory: a scalar ϕ =1/√{2 }(H +i π )≡1/√{2 }H ˜ei π ˜/⟨H ⟩ and a vector Aμ. The extended AHM (E-AHM) adds certain heavy (MΦ2,Mψ2˜MHeavy2≫⟨H ⟩2˜mWeak2 ) spin S =0 scalars Φ and S =1/2 fermions ψ . In Lorenz gauge, ∂μAμ=0 , the SSB AHM (and E-AHM) has a global U (1 )Y conserved physical current, but no conserved charge. As shown by T. W. B. Kibble, the Goldstone theorem applies, so π ˜ is a massless derivatively coupled Nambu-Goldstone boson (NGB). Proof of all-loop-orders renormalizability and unitarity for the SSB case is tricky because the Becchi-Rouet-Stora-Tyutin (BRST)-invariant Lagrangian is not U (1 )Y symmetric. Nevertheless, Slavnov-Taylor identities guarantee that on-shell T-matrix elements of physical states Aμ,ϕ , Φ , ψ (but not ghosts ω , η ¯ ) are independent of anomaly-free local U (1 )Y gauge transformations. We observe here that they are therefore also independent of the usual anomaly-free U (1 )Y global/rigid transformations. It follows that the associated global current, which is classically conserved only up to gauge-fixing terms, is exactly conserved for amplitudes of physical states in the AHM and E-AHM. We identify corresponding "undeformed" [i.e. with full global U (1 )Y symmetry] Ward-Takahashi identities (WTI). The proof of renormalizability and unitarity, which relies on BRST invariance, is undisturbed. In Lorenz gauge, two towers of "1-soft-pion" SSB global WTI govern the ϕ -sector, and represent a new global U (1 )Y⊗BRST symmetry not of the Lagrangian but of the physics. The first gives relations among off-shell Green's functions, yielding powerful constraints on the all-loop-orders ϕ -sector SSB E-AHM low-energy effective Lagrangian and an additional global shift symmetry for the NGB: π ˜→π ˜+⟨H ⟩θ . A second tower, governing on-shell T-matrix elements, replaces the old Adler
International Nuclear Information System (INIS)
Rajpoot, S.
1981-07-01
The SU(2)sub(L) x SU(2)sub(R) x U(1)sub(L+R) model of electroweak interactions is described with the most general gauge couplings gsub(L), gsub(R) and gsub(L+R). The case in which neutrino neutral current interactions are identical to the standard SU(2)sub(L) x U(1)sub(L+R) model is discussed in detail. It is shown that with the weak angle lying in the experimental range sin 2 thetaSUB(w)=0.23+-0.015 and 1 2 /gsub(R) 2 <3 it is possible to explain the amount of parity violation observed at SLAC and at the same time predict values of the ''weak charge'' in bismuth to lie in the range admitted by the controversal data from different experiments. (author)
Energy Technology Data Exchange (ETDEWEB)
Marrero, E. [Laboratorio de Termodinamica y Fisicoquimica de Fluidos (www.thermo.ulpgc.es), Parque Cientifico-Tecnologico, Campus Universitario de Tafira, Universidad de Las Palmas de Gran Canaria, 35071 Las Palmas de Gran Canaria, Canary Islands (Spain); Ortega, J. [Laboratorio de Termodinamica y Fisicoquimica de Fluidos (www.thermo.ulpgc.es), Parque Cientifico-Tecnologico, Campus Universitario de Tafira, Universidad de Las Palmas de Gran Canaria, 35071 Las Palmas de Gran Canaria, Canary Islands (Spain)], E-mail: jortega@dip.ulpgc.es; Palomar, J. [Seccion de Ingenieria Quimica, Dpto. de Quimica-Fisica Aplicada, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain)
2009-03-15
Summary: Excess enthalpies H{sub m}{sup E} and excess volumes V{sub m}{sup E} obtained at a temperature of 298.15 K and atmospheric pressure are presented for a set of 20 binary mixtures comprised of the first four propyl esters, C{sub u-1}H{sub 2u-1}COOC{sub 3}H{sub 7} (u = 1 to 4), and five {alpha},{omega}-dichloroalkanes, ClCH{sub 2}(CH{sub 2}){sub v-2}CH{sub 2}Cl (v = 2 to 6). All the mixtures are exothermic except for those corresponding to propyl methanoate with v {>=} 4. The V{sub m}{sup E} are positive in most mixtures except for those where v = 4, 5, 6, for V{sub m}{sup E}<0. There is a regular rise in H{sub m}{sup E} with v, while the increase in u produces a greater exothermicity in the mixing process, which becomes inverted for propyl butanoate. The variation in V{sub m}{sup E} with the chain length of the compounds of the mixtures studied is not regular since both the enthalpic and the volumetric effects are due to interactions of different nature, positive and negative. Interpretation of the behavior was assisted by applying the quantum-chemistry method COSMO-RS. This method describes qualitatively and quantitatively the contribution of the different types of interactions, electrostatic, van der Waals, and those due to the (Cl, Cl) bond in the dihalide, and the influence of the ester and dichloroalkane chains. This information was also useful to adequately modify the application of the UNIFAC group contribution model, proposing parameters for the Cl, Cl/carboxylate interaction that vary with the chain length of the compounds involved. With this modification, the results estimated by UNIFAC model can be considered good.
Energy Technology Data Exchange (ETDEWEB)
Ortega, J. [Laboratorio de Termodinamica y Fisicoquimica de Fluidos, Parque Cientifico-Tecnologico, Campus Universitario de Tafira, Universidad de Las Palmas de Gran Canaria, 35071 Las Palmas de Gran Canaria, Canary Islands (Spain)]. E-mail: jortega@dip.ulpgc.es; Marrero, E. [Laboratorio de Termodinamica y Fisicoquimica de Fluidos, Parque Cientifico-Tecnologico, Campus Universitario de Tafira, Universidad de Las Palmas de Gran Canaria, 35071 Las Palmas de Gran Canaria, Canary Islands (Spain)
2007-05-15
The experimental data of excess molar enthalpies H{sub m}{sup E} and excess molar volumes V{sub m}{sup E} are presented for a set of 25 binary mixtures comprised of the first five methyl esters C{sub u-1}H{sub 2u-1}COOCH{sub 3} (u=1 to 5) and five {alpha},{omega}-dichloroalkanes, ClCH{sub 2}(CH{sub 2}){sub v-2}CH{sub 2}Cl (v=2 to 6), obtained at a temperature of 298.15K and atmospheric pressure. Except for the mixtures with u=1 and v=2 to 6, which are all endothermic and with u=5 and v=2 to 6, which are all exothermic, the others present net endo/exothermic effects and these mixing effects evolve quasiregularly, from endothermic to exothermic, depending on the dichloroalkane present. However, the V{sub m}{sup E} are positive in most mixtures except for those corresponding to u=4,5 and v=5,6, which present contraction effects. These results indicate a set of specific interactions with simultaneous effects for V{sub m}{sup E} of expansion/contraction and for exothermic/endothermic H{sub m}{sup E} for this set of mixtures. The change in V{sub m}{sup E} with the chain length of the compounds is irregular. To achieve a good application of the UNIFAC model using the version of Dang and Tassios, parameters of the ester (G)/dichloride (G') interaction were calculated again, making a distinction, during its application, dependent on the acid part of the ester u. Hence, interaction parameters are presented as a function of u, and of the dichloroalkane chain length v. The most appropriate general expression was of the type:a{sub G/G{sup '}}={phi}(u,v)={sigma}sub(i=0)sup(n)a{sub i-1}u{sup i-1}+{sigma}sub(i=0= )sup(n)b{sub i-1}v{sup i-1}and with this proposal good estimations of enthalpies were obtained with the UNIFAC model.
Directory of Open Access Journals (Sweden)
Lorenzo Ferri
2016-01-01
Full Text Available Fabry disease is a rare X-linked lysosomal storage disorder caused by deficiency of the α-galactosidase A (α-Gal A enzyme, which is encoded by the GLA gene. GLA transcription in humans produces a major mRNA encoding α-Gal A and a minor mRNA of unknown function, which retains a 57-nucleotide-long cryptic exon between exons 4 and 5, bearing a premature termination codon. NM_000169.2:c.639+861C>T and NM_000169.2:c.639+919G>A GLA deep intronic mutations have been described to cause Fabry disease by inducing overexpression of the alternatively spliced mRNA, along with a dramatic decrease in the major one. Here, we built a wild-type GLA minigene and two minigenes that carry mutations c.639+861C>T and c.639+919G>A. Once transfected into cells, the minigenes recapitulate the molecular patterns observed in patients, at the mRNA, protein, and enzymatic level. We constructed a set of specific double-target U1asRNAs to correct c.639+861C>T and c.639+919G>A GLA mutations. Efficacy of U1asRNAs in inducing the skipping of the cryptic exon was evaluated upon their transient co-transfection with the minigenes in COS-1 cells, by real-time polymerase chain reaction (PCR, western blot analysis, and α-Gal A enzyme assay. We identified a set of U1asRNAs that efficiently restored α-Gal A enzyme activity and the correct splicing pathways in reporter minigenes. We also identified a unique U1asRNA correcting both mutations as efficently as the mutation-specific U1asRNAs. Our study proves that an exon skipping-based approach recovering α-Gal A activity in the c.639+861C>T and c.639+919G>A GLA mutations is active.
International Nuclear Information System (INIS)
Marrero, E.; Ortega, J.; Palomar, J.
2009-01-01
Summary: Excess enthalpies H m E and excess volumes V m E obtained at a temperature of 298.15 K and atmospheric pressure are presented for a set of 20 binary mixtures comprised of the first four propyl esters, C u-1 H 2u-1 COOC 3 H 7 (u = 1 to 4), and five α,ω-dichloroalkanes, ClCH 2 (CH 2 ) v-2 CH 2 Cl (v = 2 to 6). All the mixtures are exothermic except for those corresponding to propyl methanoate with v ≥ 4. The V m E are positive in most mixtures except for those where v = 4, 5, 6, for V m E m E with v, while the increase in u produces a greater exothermicity in the mixing process, which becomes inverted for propyl butanoate. The variation in V m E with the chain length of the compounds of the mixtures studied is not regular since both the enthalpic and the volumetric effects are due to interactions of different nature, positive and negative. Interpretation of the behavior was assisted by applying the quantum-chemistry method COSMO-RS. This method describes qualitatively and quantitatively the contribution of the different types of interactions, electrostatic, van der Waals, and those due to the (Cl, Cl) bond in the dihalide, and the influence of the ester and dichloroalkane chains. This information was also useful to adequately modify the application of the UNIFAC group contribution model, proposing parameters for the Cl, Cl/carboxylate interaction that vary with the chain length of the compounds involved. With this modification, the results estimated by UNIFAC model can be considered good
Scalet, Daniela; Sacchetto, Claudia; Bernardi, Francesco; Pinotti, Mirko; van de Graaf, Stan F J; Balestra, Dario
2018-05-01
In tyrosinaemia type 1(HT1), a mosaic pattern of fumarylacetoacetase (FAH) immunopositive or immunonegative nodules in liver tissue has been reported in many patients. This aspect is generally explained by a spontaneous reversion of the mutation into a normal genotype. In one HT1 patient carrying the frequent FAH c.1062+5G>A mutation, a second somatic change (c.1061C>A) has been reported in the same allele, and found in immunopositive nodules. Here, we demonstrated that the c.1062+5G>A prevents usage of the exon 12 5' splice site (ss), even when forced by an engineered U1snRNA specifically designed on the FAH 5'ss to strengthen its recognition. Noticeably the new somatic c.1061C>A change, in linkage with the c.1062+5G>A mutation, partially rescues the defective 5'ss and is associated to trace level (~5%) of correct transcripts. Interestingly, this combined genetic condition strongly favored the rescue by the engineered U1snRNA, with correct transcripts reaching up to 60%. Altogether, these findings elucidate the molecular basis of HT1 caused by the frequent FAH c.1062+5G>A mutation, and demonstrate the compensatory effect of the c.1061C>A change in promoting exon definition, thus unraveling a rare mechanism leading to FAH immune-reactive mosaicism.
Alberts, Jules; Finders, Anton; Martens, Harrie; Obreza, Matija; Schaeps, Leon; Slootmaker, Aad; Slot, Wim; Storm, Jeroen; Ternier, Stefaan; Van der Vegt, Wim; Vogten, Hubert
2013-01-01
Alberts, J., Finders, A., Martens, H., Obreza, M., Schaeps, L., Slootmaker, A., Slot, W., Storm, J., Ternier, S., Van der Vegt, W., & Vogten, H. (2012). OpenU (Version 1.0) [Software]. Heerlen, The Netherlands: Open Universiteit. Available under the GNU Lesser General Public License (LGPL3).
Chiral composite fermions without U(1)'s
International Nuclear Information System (INIS)
Nelson, A.E.
1986-01-01
Some models are discussed which seem likely to produce composite fermions with masses protected only by nonabelian global symmetries. A subgroup of the original global symmetries can be weakly gauged to produce small masses for the fermions. A new feature of these models is that the original global symmetries contain no abelian factors and below the confinement scale there are neither exactly massless fermions nor Goldstone bosons. A candidate is given for a potentially realistic model with up to six families of quarks and leptons. (orig.)
Berman, Theodore; Pumphrey, Norman E.
1950-01-01
An investigation has been conducted in the Langley 20-foot free-spinning tunnel to determine the spin and recovery characteristics of a 0.057-scale model of the modified Chance Vought XF7U-1 airplane. The primary change in the design from that previously tested was a revision of the twin vertical tails. Tests were also made to determine the effect of installation of external wing tanks. The results indicated that the revision in the vertical tails did not greatly alter the spin and recovery characteristics of the model and recovery by normal use of controls (fill rapid rudder reversal followed approximately one-half turn later by movement of the stick forward of neutral) was satisfactory. Adding the external wing tanks to cause the recovery characteristics to become critical and border on an unsatisfactory condition; however, it was shown that satisfactory recovery could be obtained by jettisoning the tanks, followed by normal recovery technique.
Lynn, Bryan W.; Starkman, Glenn D.
2017-09-01
In the S U (2 )L×S U (2 )R linear sigma model with partially conserved axial-vector currents, a tower of Ward-Takahashi identities (WTI) have long been known to give relations among 1-scalar-particle-irreducible (1 -ϕ -I ) Green's functions, and among I-scalar-particle-reducible (1 -ϕ -R ) transition-matrix (T-matrix) elements for external scalars [i.e. the Brout-Englert-Higgs (BEH) scalar H , and three pseudoscalars π →]. In this paper, we extend these WTI and the resulting relations to the S U (3 )C×S U (2 )L×U (1 )Y linear sigma model including the heaviest generation of Standard Model (SM) fermions—the ungauged (i.e. global) Standard Model SMtb τ ντ G —supplemented with the minimum necessary neutrino content—right-handed neutrinos and Yukawa-coupling-induced Dirac neutrino mass—to obtain the charge-parity (C P )-conserving νDSMtb τ ντ G , and extract powerful constraints on the effective Lagrangian: e.g. showing that they make separate tadpole renormalization unnecessary, and guarantee infrared finiteness. The crucial observation is that ultraviolet quadratic divergences (UVQD), and all other relevant operators, contribute only to mπ2, a pseudo-Nambu-Goldstone boson (NGB) mass-squared, which appears in intermediate steps of calculations. A WTI between T-matrix elements (or, in this global theory equivalently the Goldstone theorem) then enforces mπ2=0 exactly for the true NGB in the spontaneous symmetry breaking (SSB) mode of the theory. The Goldstone theorem thus causes all relevant operator contributions, originating to all-loop-orders from virtual scalars H ,π → , quarks qLc;tRc;bRc and leptons lL;ντR;τR with (c =r , w , b ), to vanish identically. We show that our regularization-scheme-independent, WTI-driven results are unchanged by the addition of certain S U (3 )C×S U (2 )L×U (1 )Y heavy (MHeavy2≫|q2|,mWeak2 ) C P -conserving matter, such as originate in certain beyond the SM (BSM) models. The global axial-vector WTI
Kadokura, M; Wada, T; Seio, K; Sekine, M
2000-08-25
4-Thiouridine, 6-thioguanosine, and 6-thioinosine 3',5'-bisphosphates (9, 20, and 28) were synthesized in good yields by considerably improved methods. In the former two compounds, uridine and 2-N-phenylacetylguanosine were converted via transient O-trimethylsilylation to the corresponding 4- and 6-O-benzenesulfonyl intermediates (2 and 13), which, in turn, were allowed to react with 2-cyanoethanethiol in the presence of N-methylpyrrolidine to give 4-thiouridine (3) and 2-N-phenylacetyl-6-thioguanosine derivatives (14), respectively. In situ dimethoxytritylation of these thionucleoside derivatives gave the 5'-masked products 4 and 15 in high overall yields from 1 and 11. 6-S-(2-Cyanoethyl)-5'-O-(4,4'-dimethoxytrityl)-6-thioinosine (23) was synthesized via substitution of the 5'-O-tritylated 6-chloropurine riboside derivative 22 with 2-cyanoethanethiol. These S-(2-cyanoethyl)thionucleosides were converted to the 2'-O-(tert-butyldimethylsilyl)ribonucleoside 3'-phosphoramidite derivatives 7, 18, and 26 or 3',5'-bisphosphate derivatives 8, 19, and 27. Treatment of 8, 19, and 27 with DBU gave thionucleoside 3',5'-bisphosphate derivatives 9, 20, and 28, which were found to be substrates of T4 RNA ligase. These thionucleoside 3',5'-bisphosphates were examined as donors for ligation with m3(2,2,7) G5'pppAmUmA, i.e., the 5'-terminal tetranucleotide fragment of U1 snRNA, The 4-thiouridine 3',5'-bisphosphate derivative 9 was found to serve as the most active substrate of T4 RNA ligase with a reaction efficiency of 96%.
Sawyer, Richard H.; Trant, James P., Jr.
1950-01-01
An investigation was made by the NACA wing-flow method to determine the drag, pitching-moment, lift, and angle-of-attack characteristics at transonic speeds of various configurations of a semispan model of an early configuration of the XF7U-1 tailless airplane. The results of the tests indicated that for the basic configuration with undeflected ailavator, the zero-lift drag rise occurred at a Mach number of about 0.85 and that about a five-fold increase in drag occurred through the transonic speed range. The results of the tests also indicated that the drag increment produced by -8.0 degrees deflection of the ailavator increased with increase in normal-force coefficient and was smaller at speeds above than at speeds below the drag rise. The drag increment produced by 35 degree deflection of the speed brakes varied from 0.040 to 0.074 depending on the normal-force coefficient and Mach number. These values correspond to drag coefficients of about 0.40 and 0.75 based on speed-brake frontal area. Removal of the fin produced a small positive drag increment at a given normal-force coefficient at speeds during the drag rise. A large forward shift of the neutral-point location occurred at Mach numbers above about 0.90 upon removal of the fin, and also a considerable forward shift throughout the Mach number range occurred upon deflection of the speed brakes. Ailavator ineffectiveness or reversal at low deflections, similar to that determined in previous tests of the basic configuration of the model in the Mach number range from about 0.93 to 1.0, was found for the fin-off configuration and for the model equipped with skewed (more highly sweptback) hinge-line ailavators. With the speed brakes deflected, little or no loss in the incremental pitching moment produced by deflection of the ailavator from O degrees to -8.00 degrees occurred in the Mach number range from 0.85 to 1.0 in contrast to a considerable loss found in previous tests with the speed brakes off.
Czech Academy of Sciences Publication Activity Database
Huranová, Martina; Hnilicová, Jarmila; Fleischer, Branislav; Cvačková, Zuzana; Staněk, David
2009-01-01
Roč. 18, č. 11 (2009), s. 2014-2023 ISSN 0964-6906 R&D Projects: GA AV ČR KAN200520801 Grant - others: Max Planck Society(DE) Partner group program Institutional research plan: CEZ:AV0Z50520514 Keywords : retinitis pigmentosa * snRNP * splicing Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 7.386, year: 2009
Electroweak Supersymmetry with an Approximate U(1)_PQ
Energy Technology Data Exchange (ETDEWEB)
Hall, L.J.; Watari, T.
2004-05-12
A predictive framework for supersymmetry at the TeV scale is presented, which incorporates the Ciafaloni-Pomarol mechanism for the dynamical determination of the \\mu parameter of the MSSM. It is replaced by (\\lambda S), where S is a singlet field, and the axion becomes a heavy pseudoscalar, G, by adding a mass, m_G, by hand. The explicit breaking of Peccei-Quinn (PQ) symmetry is assumed to be sufficiently weak at the TeV scale that the only observable consequence is the mass m_G. Three models for the explicit PQ breaking are given; but the utility of this framework is that the predictions for all physics at the electroweak scale are independent of the particular model for PQ breaking. Our framework leads to a theory similar to the MSSM, except that \\mu is predicted by the Ciafaloni-Pomarol relation, and there are light, weakly-coupled states in the spectrum. The production and cascade decay of superpartners at colliders occurs as in the MSSM, except that there is one extra stage of the cascade chain, with the next-to-LSP decaying to its"superpartner" and \\tilde{s}, dramatically altering the collider signatures for supersymmetry. The framework is compatible with terrestrial experiments and astrophysical observations for a wide range of m_G and. If G is as light as possible, 300 keV< m_G< 3 MeV, it can have interesting effects on the radiation energy density during the cosmological eras of nucleosynthesis and acoustic oscillation, leading to predictions for N_{\
Axial U(1) current in Grabowska and Kaplan's formulation
Hamada, Yu; Kawai, Hikaru
2017-06-01
Recently, Grabowska and Kaplan [Phys. Rev. Lett. 116, 211602 (2016); Phys. Rev. D 94, 114504 (2016)] suggested a nonperturbative formulation of a chiral gauge theory, which consists of the conventional domain-wall fermion and a gauge field that evolves by gradient flow from one domain wall to the other. We introduce two sets of domain-wall fermions belonging to complex conjugate representations so that the effective theory is a 4D vector-like gauge theory. Then, as a natural definition of the axial-vector current, we consider a current that generates simultaneous phase transformations for the massless modes in 4 dimensions. However, this current is exactly conserved and does not reproduce the correct anomaly. In order to investigate this point precisely, we consider the mechanism of the conservation. We find that this current includes not only the axial current on the domain wall but also a contribution from the bulk, which is nonlocal in the sense of 4D fields. Therefore, the local current is obtained by subtracting the bulk contribution from it.
Lifescience Database Archive (English)
Full Text Available bidopsis Thaliana Molecule: 5-Methyltetrahydropteroyltriglutamate-- Homocysteine Methyltransferase; Chain: A...QKDEALFSANAAALASRRSSPRVTNEGVQKAAAALKGSDHRRATNVSARLDAQQKKLNLPILPTTTIGSFPQTVELRRVRREYKAKKVSEEDYVKAI...GPVTILNWSFVRNDQPRHETCYQIALAIKDEVEDLEKGGIGVIQIDEAALREGLPLRKSEHAFYLDWAVHSFRITNCGVQDSTQIHTHMCYSHFNDIIHSIIDMDADV
Anomaly driven signatures of extra U(1)'s
Antoniadis, Ignatios; Ruchayskiy, Oleg
2010-01-01
Anomaly cancellation between different sectors of a theory may mediate new interactions between gauge bosons. Such interactions lead to observable effects both at precision laboratory experiments and at accelerators. Such experiments may reveal the presence of hidden sectors or hidden extra dimensions.
Extra U(1), effective operators, anomalies and dark matter
Dudas, Emilian; Mambrini, Yann; Zaldivar, Bryan
2013-01-01
A general analysis is performed on the dimension-six operators mixing an almost hidden Z' to the Standard Model (SM), when the Z' communicates with the SM via heavy mediators. These are fermions charged under both Z' and the SM, while all SM fermions are neutral under Z'. We classify the operators as a function of the gauge anomalies behaviour of mediators and explicitly compute the dimension-six operators coupling Z' to gluons, generated at one-loop by chiral but anomaly-free, sets of fermion mediators. We prove that only one operator contribute to the couplings between Z' charged matter and on-shell gluons. We then make a complete phenomenological analysis of the scenario where the lightest fermion charged under Z' is the dark matter candidate. Combining results from WMAP/PLANCK data, mono-jet searches at LHC, and direct/indirect dark matter detections restrict considerably the allowed parameter space.
U1/U2 crib groundwater biological treatment demonstration project
International Nuclear Information System (INIS)
Koegler, S.S.; Brouns, T.M.; Heath, W.O.
1989-11-01
The primary objective of the biological treatment project is to develop and demonstrate a process for Hanford groundwater remediation. Biodenitrification using facultative anaerobic microorganisms is a promising technology for the simultaneous removal of nitrates and organics from contaminated aqueous streams. During FY 1988, a consortium of Hanford groundwater microorganisms was shown to degrade both nitrates and carbon tetrachloride (CC1 4 ). A pilot-scale treatment system was designed and constructed based on the results of laboratory-and-bench-scale testing. This report summarizes the results of biological groundwater treatment studies performed during FY 1989 at the pilot-scale. These tests were conducted using a simulated Hanford groundwater with a continuous stirred-tank bioreactor, and a fluidized-bed bioreactor that was added to the pilot-scale treatment system in FY 1989. The pilot-scale system demonstrated continuous degradation of nitrates and CC1 4 in a simulated groundwater. 4 refs., 7 figs., 1 tab
Higher U(1)-gerbe connections in geometric prequantization
Czech Academy of Sciences Publication Activity Database
Fiorenza, D.; Rogers, C. L.; Schreiber, Urs
2016-01-01
Roč. 28, č. 6 (2016), s. 1650012 ISSN 0129-055X Institutional support: RVO:67985840 Keywords : geometric quantization * higher differential geometry Subject RIV: BA - General Mathematics Impact factor: 1.426, year: 2016 http://www.worldscientific.com/doi/10.1142/S0129055X16500124
CryoEM structures of two spliceosomal complexes: starter and dessert at the spliceosome feast.
Nguyen, Thi Hoang Duong; Galej, Wojciech P; Fica, Sebastian M; Lin, Pei-Chun; Newman, Andrew J; Nagai, Kiyoshi
2016-02-01
The spliceosome is formed on pre-mRNA substrates from five small nuclear ribonucleoprotein particles (U1, U2, U4/U6 and U5 snRNPs), and numerous non-snRNP factors. Saccharomyces cerevisiae U4/U6.U5 tri-snRNP comprises U5 snRNA, U4/U6 snRNA duplex and approximately 30 proteins and represents a substantial part of the spliceosome before activation. Schizosaccharomyces pombe U2.U6.U5 spliceosomal complex is a post-catalytic intron lariat spliceosome containing U2 and U5 snRNPs, NTC (nineteen complex), NTC-related proteins (NTR), U6 snRNA, and an RNA intron lariat. Two recent papers describe near-complete atomic structures of these complexes based on cryoEM single-particle analysis. The U4/U6.U5 tri-snRNP structure provides crucial insight into the activation mechanism of the spliceosome. The U2.U6.U5 complex reveals the striking architecture of NTC and NTR and important features of the group II intron-like catalytic RNA core remaining after spliced mRNA is released. These two structures greatly advance our understanding of the mechanism of pre-mRNA splicing. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Energy Technology Data Exchange (ETDEWEB)
Espinosa G, J.M. [Central Nucleoelectrica Laguna Verde, Carretera Cardel-Nautla Km. 45.5, Municipio de Alto Lucero, Veracruz (Mexico)
2006-07-01
The Laguna Verde Central from the beginning of the commercial operation settled down as maximum priority 'the total safety in its operation' taking in consideration the so much experience of the good operation and of multiple recharges made in a sure and reliable way, and without separate us of the safety mystic of the CLV, but looking for to be better every day a new challenge it settled down 'to compare us with the best plants in the world' and certainly to work to classify us like one of them. For this we established a 4.0 year old plan (2003/2006) for the effectiveness all the processes in the power station that allowed us to measure our acting with the same parameters that settle down at international level (nuclear safety, industrial safety, radiological safety, capacity factor, readiness factor, cleaning of the power station, attachment to procedures, attention to the detail and certainly to be competitive in the economic aspect, summing up means to be good in all the aspects). All the above mentioned would allow us to qualify us as level 1 of WANO (world proprietors association of nuclear centrals) at the end of the year 2006 and to pass to be part of this select group. After analyzing the acting record of the power station, evaluating our technical and economic capacity, the location of the installation besides revising the international experiences was defined that one of the concepts that impact considerably so much to the capacity factors and availability besides the dose and production cost is the duration of the recharge periods, for this reason the present work is elaborated. (Author)
Spinal Muscular Atrophy: From Defective Chaperoning of snRNP Assembly to Neuromuscular Dysfunction
Directory of Open Access Journals (Sweden)
Maia Lanfranco
2017-06-01
Full Text Available Spinal Muscular Atrophy (SMA is a neuromuscular disorder that results from decreased levels of the survival motor neuron (SMN protein. SMN is part of a multiprotein complex that also includes Gemins 2–8 and Unrip. The SMN-Gemins complex cooperates with the protein arginine methyltransferase 5 (PRMT5 complex, whose constituents include WD45, PRMT5 and pICln. Both complexes function as molecular chaperones, interacting with and assisting in the assembly of an Sm protein core onto small nuclear RNAs (snRNAs to generate small nuclear ribonucleoproteins (snRNPs, which are the operating components of the spliceosome. Molecular and structural studies have refined our knowledge of the key events taking place within the crowded environment of cells and the numerous precautions undertaken to ensure the faithful assembly of snRNPs. Nonetheless, it remains unclear whether a loss of chaperoning in snRNP assembly, considered as a “housekeeping” activity, is responsible for the selective neuromuscular phenotype in SMA. This review thus shines light on in vivo studies that point toward disturbances in snRNP assembly and the consequential transcriptome abnormalities as the primary drivers of the progressive neuromuscular degeneration underpinning the disease. Disruption of U1 snRNP or snRNP assembly factors other than SMN induces phenotypes that mirror aspects of SMN deficiency, and splicing defects, described in numerous SMA models, can lead to a DNA damage and stress response that compromises the survival of the motor system. Restoring the correct chaperoning of snRNP assembly is therefore predicted to enhance the benefit of SMA therapeutic modalities based on augmenting SMN expression.
Mixing angles in SU(2)/sub L/ x U(1) gauge model
International Nuclear Information System (INIS)
Nandi, S.; Tanaka, K.
1979-01-01
Exact expressions for the mixing parameters are obtained in terms of mass ratios in the standard Weinberg-Salam model with permutation symmetry S 3 for six quarks. The CP-violating phase is ignored, and there are no arbitrary parameters except for the quark masses. In the lowest order, the angles defined by Kobayashi-Maskawa are sin theta/sub 1/ = sin theta/sub c/ = (m/sub d//m/sub d/ + m/sub s/)/sup 1/2/, sin theta 3 = -sin theta/sub 3/ = -m 2 /sub s//m 2 /sub b/, and m/sub t/m/sub s/ greater than or equal to m/sub c/m/sub b/ = 7.2 GeV 2 or m/sub t/ greater than or equal to 24 GeV for m/sub s/ = 0.3 GeV
The Excited Spin State of 1I/2017 U1 ‘Oumuamua
Belton, Michael J. S.; Hainaut, Olivier R.; Meech, Karen J.; Mueller, Beatrice E. A.; Kleyna, Jan T.; Weaver, Harold A.; Buie, Marc W.; Drahus, Michał; Guzik, Piotr; Wainscoat, Richard J.; Waniak, Wacław; Handzlik, Barbara; Kurowski, Sebastian; Xu, Siyi; Sheppard, Scott S.; Micheli, Marco; Ebeling, Harald; Keane, Jacqueline V.
2018-04-01
We show that ‘Oumuamua’s excited spin could be in a high-energy long axis mode (LAM) state, which implies that its shape could be far from the highly elongated shape found in previous studies. CLEAN and ANOVA algorithms are used to analyze ‘Oumuamua’s lightcurve using 818 observations over 29.3 days. Two fundamental periodicities are found at frequencies (2.77 ± 0.11) and (6.42 ± 0.18) cycles/day, corresponding to (8.67 ± 0.34) hr and (3.74 ± 0.11) hr, respectively. The phased data show that the lightcurve does not repeat in a simple manner, but approximately shows a double minimum at 2.77 cycles/day and a single minimum at 6.42 cycles/day. ‘Oumuamua could be spinning in either the LAM or short axis mode (SAM). For both, the long axis precesses around the total angular momentum vector with an average period of (8.67 ± 0.34) hr. For the three LAMs we have found, the possible rotation periods around the long axis are 6.58, 13.15, or 54.48 hr, with 54.48 hr being the most likely. ‘Oumuamua may also be nutating with respective periods of half of these values. We have also found two possible SAM states where ‘Oumuamua oscillates around the long axis with possible periods at 13.15 and 54.48 hr. In this case any nutation occurs with the same periods. Determination of the spin state, the amplitude of the nutation, the direction of the total angular momentum vector (TAMV), and the average total spin period may be possible with a direct model fit to the lightcurve. We find that ‘Oumuamua is “cigar-shaped,” if close to its lowest rotational energy, and an extremely oblate spheroid if close to its highest energy state.
New signals for vector-like down-type quark in U(1) of E_6
Das, Kasinath; Li, Tianjun; Nandi, S.; Rai, Santosh Kumar
2018-01-01
We consider the pair production of vector-like down-type quarks in an E_6 motivated model, where each of the produced down-type vector-like quark decays into an ordinary Standard Model light quark and a singlet scalar. Both the vector-like quark and the singlet scalar appear naturally in the E_6 model with masses at the TeV scale with a favorable choice of symmetry breaking pattern. We focus on the non-standard decay of the vector-like quark and the new scalar which decays to two photons or two gluons. We analyze the signal for the vector-like quark production in the 2γ +≥ 2j channel and show how the scalar and vector-like quark masses can be determined at the Large Hadron Collider.
Study on Surface Structure of U1-yGdyO2-x Using Raman Spectroscopy
Energy Technology Data Exchange (ETDEWEB)
Lee, Jeong Mook; Kim, Jan Dee; Youn, Young Sang; Kim, Jong Goo; Ha, Yeong Keong; Kim, Jong Yun [KAERI, Daejeon (Korea, Republic of)
2016-05-15
To understand the structural character of the spent nuclear fuel, rare earth element (REE) doped UO{sub 2±x} have been studied as simulated spent fuel. The REE doping effect has influence on the phase stability in U-FP-O system, thermal conductivity and the relevant fuel performance. Raman spectroscopy has been used to investigate surface structure of the nuclear fuel materials, because of its sensitivity, convenience and non-destructive sample preparation. The Raman studies on trivalent-doped UO{sub 2} directly show the defect due to oxygen vacancy that could be created by loss of oxygen for charge compensation. This defect has significant effect on the kinetics of fuel oxidation. In this study, we have been investigated the effect on Gd-doping on the UO{sub 2} structure with Raman spectroscopy to characterize the defect structure of nuclear fuel material. The oxygen deficiencies of pellets were estimated by the relation between the doping concentration and a lattice parameter evaluated from XRD spectra. The Raman spectra of U{sub 1-y}GdyO{sub 2-x} solid solution pellets show the distorted fluorite structure with defect structure due to oxygen vacancies with increasing Gd contents.
Strongest experimental constraints on SU(5)×U(1) supergravity models
Lopez, Jorge L.; Nanopoulos, D. V.; Park, Gye T.; Zichichi, A.
1994-01-01
We consider a class of well-motivated string-inspired flipped SU(5) supergravity models which include four supersymmetry-breaking scenarios: no-scale, strict no-scale, dilaton, and special dilaton, such that only three parameters are needed to describe all new phenomena (mt,tanβ,mg~). We show that the CERN LEP precise measurements of the electroweak parameters in the form of the ɛ1 variable and the CLEO II allowed range for B(b-->sγ) are at present the most important experimental constraints on this class of models. For mt>~155 (165) GeV, the ɛ1 constraint [at 90 (95)% C.L.] requires the presence of light charginos (m+/-χ1360 GeV, mq~sγ) constraint excludes a significant fraction of the otherwise allowed region in the (m+/-χ1,tanβ) plane (irrespective of the magnitude of the chargino mass), while future experimental improvements will result in decisive tests of these models. In light of the ɛ1 constraint, we conclude that the outlook for chargino and selectron detection at LEP II and at DESY HERA is quite favorable in this class of models.
Strongest experimental constraints on SU(5)xU(1) supergravity models
International Nuclear Information System (INIS)
Lopez, J.L.; Nanopoulos, D.V.; Park, G.T.; Zichichi, A.
1994-01-01
We consider a class of well-motivated string-inspired flipped SU(5) supergravity models which include four supersymmetry-breaking scenarios: no-scale, strict no-scale, dilaton, and special dilaton, such that only three parameters are needed to describe all new phenomena (m t ,tanβ,m g ). We show that the CERN LEP precise measurements of the electroweak parameters in the form of the ε 1 variable and the CLEO II allowed range for B(b→sγ) are at present the most important experimental constraints on this class of models. For m t approx-gt 155 (165) GeV, the ε 1 constraint [at 90 (95)% C.L.] requires the presence of light charginos (m χ1 ± approx-lt 50--100 GeV depending on m t ). Since all sparticle masses are proportional to m g , m χ1 ± approx-lt 100 GeV implies m χ1 0 approx-lt 55 GeV, m χ2 0 approx-lt 100 GeV, m g approx-lt 360 GeV, m q approx-lt 350 (365) GeV, m e R approx-lt 80 (125) GeV, m e L approx-lt 120 (155) GeV, and m n u approx-lt 100 (140) GeV in the no-scale (dilaton) flipped SU(5) supergravity model. The B(b→sγ) constraint excludes a significant fraction of the otherwise allowed region in the (m χ1 ± ,tanβ) plane (irrespective of the magnitude of the chargino mass), while future experimental improvements will result in decisive tests of these models
Anomalous U(1) models in four and five dimensions and their anomaly poles
International Nuclear Information System (INIS)
Armillis, Roberta; Coriano, Claudio; Delle Rose, Luigi; Guzzi, Marco
2009-01-01
We analyze the role played by anomaly poles in an anomalous gauge theory by discussing their signature in the corresponding off-shell effective action. The origin of these contributions, in the most general kinematical case, is elucidated by performing a complete analysis of the anomaly vertex at perturbative level. We use two independent (but equivalent) representations: the Rosenberg representation and the longitudinal/transverse (L/T) parameterization, used in recent studies of g-2 of the muon and in the proof of non-renormalization theorems of the anomaly vertex. The poles extracted from the L/T parameterization do not couple in the infrared for generic anomalous vertices, as in Rosenberg, but we show that they are responsible for the violations of unitarity in the UV region, using a class of pole-dominated amplitudes. We conclude that consistent formulations of anomalous models require necessarily the cancellation of these polar contributions. Establishing the UV significance of these terms provides a natural bridge between the anomalous effective action and its completion by a nonlocal theory. Some additional difficulties with unitarity of the mechanism of inflow in extra dimensional models with an anomalous theory on the brane, due to the presence of anomaly poles, are also pointed out.
Constraints on SU2xU1 breaking by vacuum misalignment
International Nuclear Information System (INIS)
Banks, T.
1984-01-01
We examine a proposal of Georgi and Kaplan for raising the scale of technicolor. In scalarless vectorlike technicolor models with massless techni-fermions we show that the proposal does not work. We present a simple model which realizes the Georgi-Kaplan scenario with a partially chiral technicolor group. The model requires fine tuning of the ratio of two weak coupling constants with an accuracy of O(10 -4 ). We argue that the fine-tuning problem is quite general. (orig.)
Optimization of reloading Laguna Verde Central U1/U2, Federal Electricity Commission
International Nuclear Information System (INIS)
Espinosa G, J.M.
2006-01-01
The Laguna Verde Central from the beginning of the commercial operation settled down as maximum priority 'the total safety in its operation' taking in consideration the so much experience of the good operation and of multiple recharges made in a sure and reliable way, and without separate us of the safety mystic of the CLV, but looking for to be better every day a new challenge it settled down 'to compare us with the best plants in the world' and certainly to work to classify us like one of them. For this we established a 4.0 year old plan (2003/2006) for the effectiveness all the processes in the power station that allowed us to measure our acting with the same parameters that settle down at international level (nuclear safety, industrial safety, radiological safety, capacity factor, readiness factor, cleaning of the power station, attachment to procedures, attention to the detail and certainly to be competitive in the economic aspect, summing up means to be good in all the aspects). All the above mentioned would allow us to qualify us as level 1 of WANO (world proprietors association of nuclear centrals) at the end of the year 2006 and to pass to be part of this select group. After analyzing the acting record of the power station, evaluating our technical and economic capacity, the location of the installation besides revising the international experiences was defined that one of the concepts that impact considerably so much to the capacity factors and availability besides the dose and production cost is the duration of the recharge periods, for this reason the present work is elaborated. (Author)
Study of the oscillations event of the CNLV-U1 with Wavelets techniques
International Nuclear Information System (INIS)
Amador G, R.; Nunez C, A.; Prieto G, A.; Espinosa P, G.
2004-01-01
Presently work is described and the techniques are applied of the Fourier Transformation in Short Time, the Continuous Transformation of Wavelets and the Multi resolution Analysis for the analysis of the event of oscillations of power in the Nuclear Power station of Laguna Verde Unit 1 happened in January of 1995. In general, the wavelets techniques allows to carry out studies of the different signals generated by a nuclear plant in the plane Time-frequency, Time-scale as well as the decomposition of the signals. The results obtained study presently demonstrate that the frequency of the event of oscillations in the Nuclear Power station of Laguna Verde Unit 1 are approximately 0.52 Hz for the 3 analysis techniques, besides being observed the evolution of the frequency in function of the time. (Author)
Consistency of lattice definitions of U(1) flux in Abelian projected SU(2) gauge theory
International Nuclear Information System (INIS)
Matsuki, Takayuki; Haymaker, Richard W.
2004-01-01
We reexamine the dual Abrikosov vortex under the requirement that the lattice averages of the fields satisfy exact Maxwell equations [ME]. The electric ME accounts for the total flux and the magnetic ME determines the shape of the confining string. This leads to unique and consistent definitions of flux and electric and magnetic currents at finite lattice spacing. The resulting modification of the standard DeGrand-Toussaint construction gives a magnetic current comprised of smeared monopoles
Axion inflation, proton decay, and leptogenesis in S U (5 )×U (1 )P Q
Boucenna, Sofiane M.; Shafi, Qaisar
2018-04-01
We implement inflation in a nonsupersymmetric S U (5 ) model based on a nonminimal coupling of the axion field to gravity. The isocurvature fluctuations are adequately suppressed, axions comprise the dark matter, proton lifetime estimates are of order 8 ×1034- 3 ×1035 yr , and the observed baryon asymmetry arises via nonthermal leptogenesis. The presence of low-scale colored scalars ensures unification of the Standard Model gauge couplings and also helps in stabilizing the electroweak vacuum.
Seismic qualification tests of fans of the NPP of Laguna Verde U-1 and U-2
International Nuclear Information System (INIS)
Jarvio C, G.; Garcia H, E. E.; Arguelles F, R.; Vela H, A.; Naranjo U, J. L.
2013-10-01
This work presents the results of the seismic qualification tests applied to the fans that will be installed in the control panels of the three divisions of the diesel generators of the nuclear power plant (NPP) of Laguna Verde, Unit-1 and Unit-2. This seismic qualification process of the fans was carried out using two specimens that were tested in the seismic table (vibrating) of the Engineering Institute of Universidad Nacional Autonoma de Mexico (UNAM), in accordance with the requirements of the standard IEEE 344-1975, to satisfy the established requirements of seismic qualification in the technical specifications and normative documents required by the nuclear standards, in order to demonstrate its application in the diesel generators Divisions I, II and III of the NPP. The seismic qualification tests were developed on specimens that were retired of the NPP of Laguna Verde recently with a service life of 7.75 years. (Author)
46 CFR 54.01-5 - Scope (modifies U-1 and U-2).
2010-10-01
... into Classes I, I-L (low temperature), II, II-L (low temperature), and III. Table 54.01-5(b) describes these classes and sets out additional requirements for welded pressure vessels. (c) The requirements for...-177 or part 64 of this chapter. (3) Except as provided in paragraph (c)(4) of this section, Classes I...
Gauge vs. gravity mediation in models with anomalous U(1)'s
International Nuclear Information System (INIS)
Dudas, E.; Mambrini, Y.; Romagnoni, A.; Trapletti, M.; Pokorski, S.
2009-01-01
In an attempt to implement gauge mediation in string theory, we study string effective supergravity models of supersymmetry breaking, containing anomalous gauge factors. We discuss subtleties related to gauge invariance and the stabilization of the Green-Schwarz moduli, which set non-trivial constraints on the transmission of supersymmetry breaking to MSSM via gauge interactions. Given those constraints, it is difficult to obtain the dominance of gauge mediation over gravity mediation. Furthermore, generically the gauge contributions to soft terms contain additional non-standard terms coming from D-term contributions. Motivated by this, we study the phenomenology of recently proposed hybrid models, where gravity and gauge mediations compete at the GUT scale, and show that such a scenario can respect WMAP constraints and would be easily testable at LHC.
Critical experiments on low-enriched uranium oxide system with H/U=1.25
International Nuclear Information System (INIS)
Oh, I.; Rothe, R.E.; Tuck, G.
1982-01-01
Fifteen (15) critical experiments were performed on a horizontal split table machine using 4.48%-enriched sup(235)U uranium oxide(U 3 O 8 ). The oxide was compacted to a density of 4.68g/cm 3 and placed in 152 mm cubical aluminum cans. Water was added to achive an H/U of 1.25. Various arrays of oxide cans were distributed on each half of the split table, and the separation between halves reduced until criticality occurred. The critical table separation varied from 3.59 mm to 18.40 mm. Twelve (12) experiments required the addition of a high-enriched(-93 %sup(235)U) metal or solution driver to achieve criticality. These experiments were performed in a plastic, concrete, or thin steel reflector. Three additional experiments in the plastic reflector contained either 9.3-mm- or 24.3-mm-thick plastic moderator material between the oxide cans and did not require a driver to achieve criticality. Critical uranium driver masses ranged from 9.999 kg to 14.000 kg (solution driver), and from 25.378 kg to 29.278 kg (metal driver) for 5X5X5 arrays of uranium oxide cans. Always, one or four of these 125 cans had to be removed to make room for the drivers. Therefore, the uranium oxide masses used were 1823.8 kg and 1863.5 kg. For the moderated experiments, the uranium oxide mass ranged between 574.4 kg and 1210.0 kg. (Author)
Two-color quark matter: U(1)(A) restoration, superfluidity, and quarkyonic phase
Czech Academy of Sciences Publication Activity Database
Brauner, Tomáš; Fukushima, K.; Hidaka, Y.
2009-01-01
Roč. 80, č. 7 (2009), 074035/1-074035/14 ISSN 1550-7998 Institutional research plan: CEZ:AV0Z10480505 Keywords : BARYON DENSITY * SYMMETRY BREAKING * CHIRAL-SYMMETRY * 2 COLOR QCD Subject RIV: BE - Theoretical Physics Impact factor: 4.922, year: 2009
Electroweak radiative corrections in the SU(2) x U(1) standard model
International Nuclear Information System (INIS)
Hollik, W.
1986-01-01
This paper contains a discussion of the 1-loop renormalization of the standard model and applications of the radiative corrections to fermion processes. Thereby we restrict the discussion to leptonic processes since these allow the cleanest access to the more subtle parts of the theory avoiding theoretical uncertainties as far as possible. Actual measurements of the W +- ,Z masses and of sin 2 θ W already indicate the presence of higher order effects in electroweak processes between fermions. More accurate measurements in the near future colliders LEP and SLC will allow to test the standard model beyond the tree level. At the 1-loop level a big amount of work has already been done with a satisfactory agreement between the individual calculations for the standard processes: μ decays, ν-scattering, and e + e → μ + μ - . 38 refs
Constructive tensorial group field theory II: the {U(1)-T^4_4} model
Lahoche, Vincent
2018-05-01
In this paper, we continue our program of non-pertubative constructions of tensorial group field theories (TGFT). We prove analyticity and Borel summability in a suitable domain of the coupling constant of the simplest super-renormalizable TGFT which contains some ultraviolet divergencies, namely the color-symmetric quartic melonic rank-four model with Abelian gauge invariance, nicknamed . We use a multiscale loop vertex expansion. It is an extension of the loop vertex expansion (the basic constructive technique for non-local theories) which is required for theories that involve non-trivial renormalization.
Gauge coupling running in minimal SU(3) x SU(2) x U(1) superstring unification
Ibáñez, L E; Ross, Graham G
1991-01-01
We study the evolution of the gauge coupling constants in string unification schemes in which the light spectrum below the compactification scale is exactly that of the minimal supersymmetric standard model. In the absence of string threshold corrections the predicted values $\\sin^2\\theta _W=0.218$ and $\\alpha _s=0.20$ are in gross conflict with experiment, but these corrections are generically important. One can express the string threshold corrections to $\\sin^2\\theta _W$ and $\\alpha_s$ in terms of certain $modular$ $weights$ of quark, lepton and Higgs superfields as well as the $moduli$ of the string model. We find that in order to get agreement with the experimental measurements within the context of this $minimal$ scheme, certain constraints on the $modular$ $weights$ of the quark, lepton and Higgs superfields should be obeyed. Our analysis indicates that this $minimal$ $string$ $unification$
Co-evolution of SNF spliceosomal proteins with their RNA targets in trans-splicing nematodes.
Strange, Rex Meade; Russelburg, L Peyton; Delaney, Kimberly J
2016-08-01
Although the mechanism of pre-mRNA splicing has been well characterized, the evolution of spliceosomal proteins is poorly understood. The U1A/U2B″/SNF family (hereafter referred to as the SNF family) of RNA binding spliceosomal proteins participates in both the U1 and U2 small interacting nuclear ribonucleoproteins (snRNPs). The highly constrained nature of this system has inhibited an analysis of co-evolutionary trends between the proteins and their RNA binding targets. Here we report accelerated sequence evolution in the SNF protein family in Phylum Nematoda, which has allowed an analysis of protein:RNA co-evolution. In a comparison of SNF genes from ecdysozoan species, we found a correlation between trans-splicing species (nematodes) and increased phylogenetic branch lengths of the SNF protein family, with respect to their sister clade Arthropoda. In particular, we found that nematodes (~70-80 % of pre-mRNAs are trans-spliced) have experienced higher rates of SNF sequence evolution than arthropods (predominantly cis-spliced) at both the nucleotide and amino acid levels. Interestingly, this increased evolutionary rate correlates with the reliance on trans-splicing by nematodes, which would alter the role of the SNF family of spliceosomal proteins. We mapped amino acid substitutions to functionally important regions of the SNF protein, specifically to sites that are predicted to disrupt protein:RNA and protein:protein interactions. Finally, we investigated SNF's RNA targets: the U1 and U2 snRNAs. Both are more divergent in nematodes than arthropods, suggesting the RNAs have co-evolved with SNF in order to maintain the necessarily high affinity interaction that has been characterized in other species.
Energy Technology Data Exchange (ETDEWEB)
Amador G, R.; Nunez C, A. [CNSNS, Dr. Barragan 779, 03020 Mexico D.F. (Mexico)]. E-mail: ragarcia@cnsns.gob.mx; Prieto G, A.; Espinosa P, G. [UAM-I, 09340 Mexico D.F. (Mexico)
2004-07-01
Presently work is described and the techniques are applied of the Fourier Transformation in Short Time, the Continuous Transformation of Wavelets and the Multi resolution Analysis for the analysis of the event of oscillations of power in the Nuclear Power station of Laguna Verde Unit 1 happened in January of 1995. In general, the wavelets techniques allows to carry out studies of the different signals generated by a nuclear plant in the plane Time-frequency, Time-scale as well as the decomposition of the signals. The results obtained study presently demonstrate that the frequency of the event of oscillations in the Nuclear Power station of Laguna Verde Unit 1 are approximately 0.52 Hz for the 3 analysis techniques, besides being observed the evolution of the frequency in function of the time. (Author)
Energy Technology Data Exchange (ETDEWEB)
Jarvio C, G.; Garcia H, E. E.; Arguelles F, R.; Vela H, A. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Naranjo U, J. L., E-mail: gilberto.jarvio@inin.gob.mx [Comision Federal de Electricidad, Gerencia de Centrales Nucleoelectricas, Subgerencia de Ingenieria, Carretera Veracruz-Medellin Km 7.5, Dos Bocas, Veracruz (Mexico)
2013-10-15
This work presents the results of the seismic qualification tests applied to the fans that will be installed in the control panels of the three divisions of the diesel generators of the nuclear power plant (NPP) of Laguna Verde, Unit-1 and Unit-2. This seismic qualification process of the fans was carried out using two specimens that were tested in the seismic table (vibrating) of the Engineering Institute of Universidad Nacional Autonoma de Mexico (UNAM), in accordance with the requirements of the standard IEEE 344-1975, to satisfy the established requirements of seismic qualification in the technical specifications and normative documents required by the nuclear standards, in order to demonstrate its application in the diesel generators Divisions I, II and III of the NPP. The seismic qualification tests were developed on specimens that were retired of the NPP of Laguna Verde recently with a service life of 7.75 years. (Author)
Energy Technology Data Exchange (ETDEWEB)
Zamora R, L.; Medina F, A. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)
1999-07-01
The degradation of internal components at BWR type reactors is an important subject to consider in the performance availability of the power plant. The Wuergassen nuclear reactor license was confiscated due to the presence of cracking in the core envelopment. In consequence it is necessary carrying out a detailed study with the purpose to avoid these problems in the future. This report presents a review and analysis of documents and technical information referring to the core envelopment of a BWR/5/6 and the Laguna Verde Unit 1 nuclear reactor in Mexico. In this document are presented design data, documents about fabrication processes, and manufacturing of core envelopment. (Author)
Torons, chiral symmetry breaking and U(1) problem in σ-model and in gauge theories. Part 1
International Nuclear Information System (INIS)
Zhitnitskij, A.R.
1989-01-01
A novel class of self-dual solutions in σ-models and in SU(2) gauge theories is considered. The solution is defined on manifold with boundary, it has topological charge Q=1/2. The contribution of the corresponding fluctuations and toron configurations to chiral condensate is calculated. This contribution has finite nonzero value. The APS (Atiyah, Patodi, Singer) theorem for a manifold with a boundary is discussed for the O(3) σ model. The necessity of imposing non-local boundary conditions for the Dirac operator is explained. 30 refs.; 4 figs
Directory of Open Access Journals (Sweden)
Guillermo García Fernández
2017-02-01
The result follows from strong antiscreening of the running coupling for those larger groups (with an appropriately small number of flavors together with scaling properties of the Dyson–Schwinger equation for the fermion mass.
Rare B-meson decays in SU(2)LxSU(2)RxU(1) model
International Nuclear Information System (INIS)
Asatryan, H.M.; Ioannissian, A.N.
1989-01-01
Rare B-meson decays are investigated in the left-right synmmetric models. The scalar particle contribution to the amplitude of the b → s γ decay is calculated. It is shown that this contribution can be essential even for the scalar particles masses of about several TeV. The effects due to the left-right symmetry and scalar particles can be detected by measuring the photon polarization in the decay B → K * γ. 9 refs.; 1 fig.; 1 tab
Slavnov and Gaudin-Korepin formulas for models without U (1) symmetry: the XXX chain on the segment
Belliard, S.; Pimenta, R. A.
2016-04-01
We consider the isotropic spin -\\frac{1}{2} Heisenberg chain with the most general integrable boundaries. The scalar product between the on-shell Bethe vector and its off-shell dual, obtained by means of the modified algebraic Bethe ansatz, is given by a modified Slavnov formula. The corresponding Gaudin-Korepin formula, i.e., the square of the norm, is also obtained.
Directory of Open Access Journals (Sweden)
Khan Mehbub
2018-01-01
Full Text Available Based on baryon charge conservation and a generalized Yang-Mills symmetry for Abelian (and non-Abelian groups, we discuss a new baryonic gauge field and its linear potential for two point-like baryon charges. The force between two point-like baryons is repulsive, extremely weak and independent of distance. However, for two extended baryonic systems, we have a dominant linear force α r. Thus, only in the later stage of the cosmic evolution, when two baryonic galaxies are separated by an extremely large distance, the new repulsive baryonic force can overcome the gravitational attractive force. Such a model provides a gauge-field-theoretic understanding of the late-time accelerated cosmic expansion. The baryonic force can be tested by measuring the accelerated Wu-Doppler frequency shifts of supernovae at different distances.
Torons, chiral symmetry breaking and U(1) problem in σ-model and gauge theories. Part 2
International Nuclear Information System (INIS)
Zhitnitskij, A.R.
1989-01-01
The main point of this work is the physical consenquences of the existence of fractional charge in the σ-models and espesially in the physically interesting theory QCD. It is shown that the corresponding fluctuations ensure spontaneous breaking of the chiral symmetry and give a nonzero contribution to the chiral condensate. Toron solution is determined on the manifold with boundary. In this case many questions arise such as: global boundary conditions, the stability of the solution, self-adjointness of Dirac operator, single-valuedness of the physical values and so on. These questions are interconnected and turn out to be self cobsistent only for the special choice of the topological number (Q=1/2 for SU(2)). It is shown that in the Dirac's spectrum of the quarks the gap between zero and the continuum is absent. 50 refs.; 10 figs
New signals for vector-like down-type quark in U(1) of E{sub 6}
Energy Technology Data Exchange (ETDEWEB)
Das, Kasinath; Rai, Santosh Kumar [Harish-Chandra Research Institute, HBNI, Regional Centre for Accelerator-based Particle Physics, Allahabad (India); Li, Tianjun [Chinese Academy of Sciences, CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Beijing (China); University of Chinese Academy of Sciences, School of Physical Sciences, Beijing (China); Nandi, S. [Oklahoma State University, Department of Physics and Oklahoma Center for High Energy Physics, Stillwater, OK (United States)
2018-01-15
We consider the pair production of vector-like down-type quarks in an E{sub 6} motivated model, where each of the produced down-type vector-like quark decays into an ordinary Standard Model light quark and a singlet scalar. Both the vector-like quark and the singlet scalar appear naturally in the E{sub 6} model with masses at the TeV scale with a favorable choice of symmetry breaking pattern. We focus on the non-standard decay of the vector-like quark and the new scalar which decays to two photons or two gluons. We analyze the signal for the vector-like quark production in the 2γ+ ≥ 2j channel and show how the scalar and vector-like quark masses can be determined at the Large Hadron Collider. (orig.)
Gu, Jinbao; Xia, Zhiqiang; Luo, Yuehua; Jiang, Xingyu; Qian, Bilian; Xie, He; Zhu, Jian-Kang; Xiong, Liming; Zhu, Jianhua; Wang, Zhen-Yu
2017-01-01
Soil salinity is a significant threat to sustainable agricultural production worldwide. Plants must adjust their developmental and physiological processes to cope with salt stress. Although the capacity for adaptation ultimately depends
Anyons, spin, and statistics in (2+1)-dimensional U(1)-scalar Chern-Simons gauge field theory
International Nuclear Information System (INIS)
Graziano, E.; Rothe, K.D.
1994-01-01
We present a detailed analysis of the quantum field theory of a Chern-Simons field coupled minimally to massive charged bosonic matter. This analysis is carried out in the Coulomb and covariant gauges. Some aspects concerning the transformation law of the fields under Poincare transformations are clarified. Emphasis is placed on gauge-invariant operators. The order and disorder operators are constructed from their dual algebra. The order operator is shown to obey anyonic statistics. The correlator of the disorder operator is computed in the large boson-mass limit, and the corresponding cluster properties are discussed. In the absence of a symmetry-breaking Higgs potential, there is no evidence for the ground state being anyonic
International Nuclear Information System (INIS)
Zamora R, L.; Medina F, A.
1999-01-01
The degradation of internal components at BWR type reactors is an important subject to consider in the performance availability of the power plant. The Wuergassen nuclear reactor license was confiscated due to the presence of cracking in the core envelopment. In consequence it is necessary carrying out a detailed study with the purpose to avoid these problems in the future. This report presents a review and analysis of documents and technical information referring to the core envelopment of a BWR/5/6 and the Laguna Verde Unit 1 nuclear reactor in Mexico. In this document are presented design data, documents about fabrication processes, and manufacturing of core envelopment. (Author)
Experience in the application of S.A.T. for maintenance training at Cernavoda N.P.P. - U1
International Nuclear Information System (INIS)
Erdinici, Abdula
1999-01-01
A short history of Maintenance Training at Cernavoda NPP Unit 1 will be presented highlighting the fact that: - Cernavoda NPP Unit 1 is the first nuclear power plant in Romania; - Construction/Commissioning and initial operation was done under the direct supervision of expert specialists (from Canada, Italy and US). In addition, the application of Systematic Approach to Training (S.A.T.) principles at Cernavoda NPP for all training activities will be addressed. A short history of how maintenance training activity developed over time will be detailed to address the following issues: - how the S.A.T. stages were applied; - how maintenance experience was gained during Unit 1 Construction/Commissioning initial operation and how this experience has been evaluated, credited and transferred; - how maintenance training was documented; - how the maintenance training activity is organized; - on-the-job training for maintenance personnel. Concerning other training activities at Cernavoda NPP the maintenance begins with a training needs analysis for each maintenance position. These needs are documented through Job Related Training requirements (JRTR's) produced for each maintenance position. During commissioning/initial operation, only necessary maintenance training has been delivered, such as: pump alignments, use of maintenance procedure, application of maintenance documentation. The 'hands-on' activities under expatriates specialists supervision was the main training activity. Training coordinators for each maintenance activity (Mechanical, EI. I-and-C, and Services maintenance) have been appointed to administer maintenance training. Following the declaration of the unit in commercial operation, a new approach has been taken related to maintenance Bucharest A Task Force to evaluate maintenance training status and experience has been established. This group was initiated at the Training Department initiative and it was initially co-ordinated by a Canadian maintenance specialist. Some of the outputs of this Task Force are: - carrier path for all maintenance positions; - revised JRTR's for all maintenance position; - training exception request, to recognize maintenance skills and experience gained during the commissioning/initial operation period; - long, medium and short term training schedules for maintenance personnel. Our maintenance training activities are based upon S.A.T. principles and our trainers have been indoctrinated to observe these principles. (author)
Directory of Open Access Journals (Sweden)
Robinson Melvin L
2005-07-01
Full Text Available Abstract Background The Cajal body (CB is a nuclear suborganelle involved in the biogenesis of small nuclear ribonucleoproteins (snRNPs, which are vital for pre-mRNA splicing. Newly imported Sm-class snRNPs traffic through CBs, where the snRNA component of the snRNP is modified, and then target to other nuclear domains such as speckles and perichromatin fibrils. It is not known how nascent snRNPs localize to the CB and are released from this structure after modification. The marker protein for CBs, coilin, may play a role in snRNP biogenesis given that it can interact with snRNPs and SMN, the protein mutated in Spinal Muscular Atrophy. Loss of coilin function in mice leads to significant viability and fertility problems and altered CB formation. Results In this report, we identify a minor isoform of the mitochondrial Tim50, Tim50a, as a coilin interacting protein. The Tim50a transcript can be detected in some cancer cell lines and normal brain tissue. The Tim50a protein differs only from Tim50 in that it contains an additional 103 aa N-terminal to the translation start of Tim50. Importantly, a putative nuclear localization signal is found within these 103 residues. In contrast to Tim50, which localizes to the cytoplasm and mitochondria, Tim50a is strictly nuclear and is enriched in speckles with snRNPs. In addition to coilin, Tim50a interacts with snRNPs and SMN. Competition binding experiments demonstrate that coilin competes with Sm proteins of snRNPs and SMN for binding sites on Tim50a. Conclusion Tim50a may play a role in snRNP biogenesis given its cellular localization and protein interaction characteristics. We hypothesize that Tim50a takes part in the release of snRNPs and SMN from the CB.
Schwer, Beate; Kruchten, Joshua; Shuman, Stewart
2016-09-01
A seven-subunit Sm protein ring forms a core scaffold of the U1, U2, U4, and U5 snRNPs that direct pre-mRNA splicing. Using human snRNP structures to guide mutagenesis in Saccharomyces cerevisiae, we gained new insights into structure-function relationships of the SmG, SmE, and SmF subunits. An alanine scan of 19 conserved amino acids of these three proteins, comprising the Sm RNA binding sites or inter-subunit interfaces, revealed that, with the exception of Arg74 in SmF, none are essential for yeast growth. Yet, for SmG, SmE, and SmF, as for many components of the yeast spliceosome, the effects of perturbing protein-RNA and protein-protein interactions are masked by built-in functional redundancies of the splicing machine. For example, tests for genetic interactions with non-Sm splicing factors showed that many benign mutations of SmG, SmE, and SmF (and of SmB and SmD3) were synthetically lethal with null alleles of U2 snRNP subunits Lea1 and Msl1. Tests of pairwise combinations of SmG, SmE, SmF, SmB, and SmD3 alleles highlighted the inherent redundancies within the Sm ring, whereby simultaneous mutations of the RNA binding sites of any two of the Sm subunits are lethal. Our results suggest that six intact RNA binding sites in the Sm ring suffice for function but five sites may not. © 2016 Schwer et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.
Schwer, Beate; Kruchten, Joshua; Shuman, Stewart
2016-01-01
A seven-subunit Sm protein ring forms a core scaffold of the U1, U2, U4, and U5 snRNPs that direct pre-mRNA splicing. Using human snRNP structures to guide mutagenesis in Saccharomyces cerevisiae, we gained new insights into structure–function relationships of the SmG, SmE, and SmF subunits. An alanine scan of 19 conserved amino acids of these three proteins, comprising the Sm RNA binding sites or inter-subunit interfaces, revealed that, with the exception of Arg74 in SmF, none are essential for yeast growth. Yet, for SmG, SmE, and SmF, as for many components of the yeast spliceosome, the effects of perturbing protein–RNA and protein–protein interactions are masked by built-in functional redundancies of the splicing machine. For example, tests for genetic interactions with non-Sm splicing factors showed that many benign mutations of SmG, SmE, and SmF (and of SmB and SmD3) were synthetically lethal with null alleles of U2 snRNP subunits Lea1 and Msl1. Tests of pairwise combinations of SmG, SmE, SmF, SmB, and SmD3 alleles highlighted the inherent redundancies within the Sm ring, whereby simultaneous mutations of the RNA binding sites of any two of the Sm subunits are lethal. Our results suggest that six intact RNA binding sites in the Sm ring suffice for function but five sites may not. PMID:27417296
Excitation of giant resonances in 20Ne + 90Zr and 208Pb inelastic scattering at 40 MeV/u1
International Nuclear Information System (INIS)
Suomijaervi, T.; Beaumel, D.; Blumenfeld, Y.; Chomaz, P.; Frascaria, N.; Garron, J.P.; Jacmart, J.C.; Roynette, J.C.; Kraus, L.; Link, I.
1988-01-01
The giant resonance region in the inelastic spectra from the reactions 20 Ne + 90 Zr and 20 Ne + 208 Pb at 40 MeV/nucleon has been studied with a good energy and angular resolutions. The strength distributions of the different multipolarities contributing to the cross section were obtained by a resonance shape independent analysis. In the case of 208 Pb the GDR strength was found to be strongly shifted towards lower excitation energies which can be explained by the exponentially decreasing Coulomb excitation probability. Furthermore, indications for a high multipolarity component in the resonance structure were found in both reactions
International Nuclear Information System (INIS)
Montes T, J.L.; Cortes C, C.C.
1992-08-01
This guide is applied for the reload pattern's formation for mirror symmetry of a core room and in accordance with the Control Cell core technique (of the english Control Cell Core - CCC) for the PRESTO-B code. (Author)
International Nuclear Information System (INIS)
Tijerina S, F.
2008-01-01
The engineers in nuclear power plants BWRs and PWRs based on the development of the ultrasonic technology for the measurement of the mass, volumetric flow, density and temperature in fluids, have applied this technology in two primary targets approved by the NRC: the use for the recovery of thermal power in the reactor and/or to be able to realize an increase of thermal power licensed in a 2% (MUR) by 1OCFR50 Appendix K. The present article mentions the current problem in the measurement of the feedwater flow with Venturi meters, which affects that the thermal balance of reactor BWRs or PWRs this underestimated. One in broad strokes describes the application of the ultrasonic technology for the ultrasonic measurement in the flow of the feedwater system of the reactor and power to recover thermal power of the reactor. One is to the methodology developed in CFE for a calibration of the temperature transmitters of RTD's and the methodology for a calibration of the venturi flow transmitters using ultrasonic measurement. Are show the measurements in the feedwater of reactor of the temperature with RTD's and ultrasonic measurement, as well as the flow with the venturi and the ultrasonic measurement operating the reactor to the 100% of nominal thermal power, before and after the calibration of the temperature transmitters and flow. Finally, is a plan to be able to realize a recovery of thermal power of the reactor, showing as carrying out their estimations. As a result of the application of ultrasonic technology in the feedwater of reactor BWR-5 in Laguna Verde, in the Unit 1 cycle 13 it was recover an equivalent energy to a thermal power of 25 MWt in the reactor and an exit electrical power of 6 M We in the turbogenerator. Also in the Unit 2 cycle 10 it was recover an equivalent energy to a thermal power of 40 MWt in the reactor and an exit electrical power of 16 M We in the turbogenerator. (Author)
Energy Technology Data Exchange (ETDEWEB)
Mago, R.; Franco, L.; Armas, F.; Vasquez, R.; Rodriguez, J.; Gil, E. [PDVSA EandP (Venezuela)
2011-07-01
In heavy oil and extra heavy oil fields, steam assisted gravity drainage is a thermal recovery method used to reduce oil viscosity and thus increase oil recovery. For SAGD to be successfully applied in deep reservoirs, drilling and completion of the producer and injector wells are critical. Petroleos de Venezuela SA (PDVSA) is currently assessing the feasibility of SAGD in the Orinoco oil belt in Venezuela and this paper aims at presenting the methodology used to ensure optimal drilling and completion of the project. This method was divided in several stages: planning, drilling and completion of the producer, injector and then of the observer wells and cold information capture. It was found that the use of magnetic guidance tools, injection pipe pre-insulated and pressure and temperature sensors helps optimize the drilling and completion process. A methodology was presented to standardize operational procedures in the drilling and completion of SAGD projects in the Orinoco oil belt.
Analysis of the evolution of reactivity of the event at 24/01/1995 of the BWR U-1 of Laguna Verde
International Nuclear Information System (INIS)
Ruiz E, J.A.; Blazquez M, J.
2003-01-01
In this work it is looked for, to calculate the reactivity starting from the measures of the one nuclear detection system denominated by their initials in English 'APRM' (Average Power Range Monitor) of the oscillatory event of the unit 1 of the nuclear power station of Laguna Verde happened the 24/01/1995. The reference signal consists of 3589 points taken every 0.2 seconds before the reactor operator carried out the cut of the same one. It is tried to give answer to queries like: When the event really began?, How distinguishing the stable part of the unstable? Which could be the way of predicting it?. The analysis is developed applying the call 'inverse method', with the purpose of interpreting the power response, having a mean of obtaining the information about the changes of reactivity that were given in the transitory one and to look their relationship with the actions taken by the operator. A comparison of the variation of the signal of reactivity with basic statistical variables with the purpose of trying of to find a mechanism for early detection of the instability is included. (Author)
DEFF Research Database (Denmark)
Martínez-Pizarro, Ainhoa; Dembic, Maja; Pérez, Belén
2018-01-01
Phenylketonuria (PKU), one of the most common inherited diseases of amino acid metabolism, is caused by mutations in the phenylalanine hydroxylase (PAH) gene. Recently, PAH exon 11 was identified as a vulnerable exon due to a weak 3' splice site, with different exonic mutations affecting exon 11 ...
Harvey, T. J.; Hughes, C.; Ward, A. D.; Gazi, E.; Faria, E. Correia; Clarke, N. W.; Brown, M.; Snook, R.; Gardner, P.
2008-11-01
Here we report on investigations into using Raman optical tweezers to analyse both live and chemically fixed prostate and bladder cells. Spectra were subjected to chemometric analysis to discriminate and classify the cell types based on their spectra. Subsequent results revealed the potential of Raman tweezers as a potential clinical diagnostic tool.
Sekine, Mitsuo; Kadokura, Michinori; Satoh, Takahiko; Seio, Kohji; Wada, Takeshi; Fischer, Utz; Sumpter, Vicki; Lührmann, Reinhard
1996-06-26
The 5'-terminal TMG-capped triribonucleotide, m(3)(2,2,7)G(5)(')pppAmpUmpA, has been synthesized by condensation of an appropriately protected triribonucleotide derivative of ppAmpUmpA with a new TMG-capping reagent. During this total synthesis, it was found that the regioselective 2'-O-methylation of 3',5'-O-(1,1,3,3-tetraisopropyldisiloxane-1,3-diyl)-N-(4-monomethoxytrityl)adenosine was achieved by use of MeI/Ag(2)O without affecting the base moiety. A new route to 2-N,2-N-dimethylguanosine from guanosine via a three-step reaction has also been developed by reductive methylation using paraformaldehyde and sodium cyanoborohydride. These key intermediates were used as starting materials for the construction of a fully protected derivative of pAmpUmpA and a TMG-capping reagent of Im-pm(3)(2,2,7)G. The target TMG-capped tetramer, m(3)(2,2,7)G(5)(')pppAmpUmpA, was synthesized by condensation of a partially protected triribonucleotide 5'-terminal diphosphate species, ppA(MMTr)mpUmpA, with Im-pm(3)(2,2,7)G followed by treatment with 80% acetic acid. The structure of m(3)(2,2,7)G(5)(')pppAmpUmpA was characterized by (1)H and (31)P NMR spectroscopy as well as enzymatic assay using snake venom phosphodiesterase, calf intestinal phosphatase, and nuclease P1.
International Nuclear Information System (INIS)
Flores S, V. H.
2011-01-01
In the present investigation work, were determined the parameters to simulate the conditions of internal oxidation reactor circulation pipes of the nuclear power plant of Laguna Verde in Veracruz. We used 304l stainless steel cylinders with two faces prepared with abrasive paper of No. 600, with the finality to obtain similar surface to the internal circulation piping nuclear reactor. Oxides was formed within an autoclave (Autoclave MEX-02 unit B), which is a device that simulates the working conditions of the nuclear reactor, but without radiation generated by the fission reaction within the reactor. The oxidation conditions were a temperature of 280 C and pressure of 8 MPa, similar conditions to the reactor operating in nuclear power plant of Laguna Verde in Veracruz, Mexico (BWR conditions), with an average conductivity of 4.58 ms / cm and 2352 ppb oxygen to simulate normal water chemistry NWC. Were obtained deposits of noble metal oxides formed on 304l stainless steel samples, in a 250 ml autoclave at a temperature range of 180 to 200 C. The elements that were used to deposit platinum-rhodium (Pt-Rh) with aqueous Na 2 Pt (OH) 6 and Na 3 Rh (NO 2 ) 6 , Silver (Ag) with an aqueous solution of AgNO 3 , zirconium (Zr) with aqueous Zr O (NO 3 ) and ZrO 2 , and zinc (Zn) in aqueous solution of Zn (NO 3 ) 2 under conditions of normal water chemistry. Also there was the oxidation of 304l stainless steel specimens in normal water chemistry with a solution of Zinc (Zn) (NWC + Zn). Oxidation of the specimens in water chemistry with a solution of zinc (Zn + NWC) was prepared in two ways: within the MEX-02 autoclave unit A in a solution of zinc and a flask at constant temperature in zinc solution. The oxides formed and deposits were characterized by scanning electron microscopy, energy dispersive X-ray analysis, elemental field analysis and X-ray diffraction. By other hand was evaluated the electrochemical behavior of the oxides formed on the surface of 304l stainless steel in normal water chemistry, zirconium deposits on these oxides and deposits formed in a flask at constant temperature in solution of zinc, with power noise technique and electrochemical tafel extrapolation technique. Finally, were presented the results to the nuclear as an alternative mitigation effort stress corrosion cracking (SCC) and thus give support to the nuclear power plant of Laguna Verde in the action of existing corrosion phenomenon. (Author)
Czech Academy of Sciences Publication Activity Database
Zamudio, J. R.; Mittra, B.; Foldynová-Trantírková, Silvie; Zeiner, G. M.; Lukeš, Julius; Bujnicki, J. M.; Sturm, N. R.; Campbell, D. A.
2007-01-01
Roč. 27, č. 17 (2007), s. 6084-6092 ISSN 0270-7306 R&D Projects: GA MŠk 2B06129; GA MŠk LC07032 Institutional research plan: CEZ:AV0Z60220518 Keywords : methylation * Trypanosoma brucei * methyltransferase * RNA interference Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.420, year: 2007
Theory on the Coupled Stochastic Dynamics of Transcription and Splice-Site Recognition
Murugan, Rajamanickam; Kreiman, Gabriel
2012-01-01
Eukaryotic genes are typically split into exons that need to be spliced together to form the mature mRNA. The splicing process depends on the dynamics and interactions among transcription by the RNA polymerase II complex (RNAPII) and the spliceosomal complex consisting of multiple small nuclear ribonucleo proteins (snRNPs). Here we propose a biophysically plausible initial theory of splicing that aims to explain the effects of the stochastic dynamics of snRNPs on the splicing patterns of eukaryotic genes. We consider two different ways to model the dynamics of snRNPs: pure three-dimensional diffusion and a combination of three- and one-dimensional diffusion along the emerging pre-mRNA. Our theoretical analysis shows that there exists an optimum position of the splice sites on the growing pre-mRNA at which the time required for snRNPs to find the 5′ donor site is minimized. The minimization of the overall search time is achieved mainly via the increase in non-specific interactions between the snRNPs and the growing pre-mRNA. The theory further predicts that there exists an optimum transcript length that maximizes the probabilities for exons to interact with the snRNPs. We evaluate these theoretical predictions by considering human and mouse exon microarray data as well as RNAseq data from multiple different tissues. We observe that there is a broad optimum position of splice sites on the growing pre-mRNA and an optimum transcript length, which are roughly consistent with the theoretical predictions. The theoretical and experimental analyses suggest that there is a strong interaction between the dynamics of RNAPII and the stochastic nature of snRNP search for 5′ donor splicing sites. PMID:23133354
Theory on the coupled stochastic dynamics of transcription and splice-site recognition.
Directory of Open Access Journals (Sweden)
Rajamanickam Murugan
Full Text Available Eukaryotic genes are typically split into exons that need to be spliced together to form the mature mRNA. The splicing process depends on the dynamics and interactions among transcription by the RNA polymerase II complex (RNAPII and the spliceosomal complex consisting of multiple small nuclear ribonucleo proteins (snRNPs. Here we propose a biophysically plausible initial theory of splicing that aims to explain the effects of the stochastic dynamics of snRNPs on the splicing patterns of eukaryotic genes. We consider two different ways to model the dynamics of snRNPs: pure three-dimensional diffusion and a combination of three- and one-dimensional diffusion along the emerging pre-mRNA. Our theoretical analysis shows that there exists an optimum position of the splice sites on the growing pre-mRNA at which the time required for snRNPs to find the 5' donor site is minimized. The minimization of the overall search time is achieved mainly via the increase in non-specific interactions between the snRNPs and the growing pre-mRNA. The theory further predicts that there exists an optimum transcript length that maximizes the probabilities for exons to interact with the snRNPs. We evaluate these theoretical predictions by considering human and mouse exon microarray data as well as RNAseq data from multiple different tissues. We observe that there is a broad optimum position of splice sites on the growing pre-mRNA and an optimum transcript length, which are roughly consistent with the theoretical predictions. The theoretical and experimental analyses suggest that there is a strong interaction between the dynamics of RNAPII and the stochastic nature of snRNP search for 5' donor splicing sites.
Energy Technology Data Exchange (ETDEWEB)
Flores S, V. H.
2011-07-01
In the present investigation work, were determined the parameters to simulate the conditions of internal oxidation reactor circulation pipes of the nuclear power plant of Laguna Verde in Veracruz. We used 304l stainless steel cylinders with two faces prepared with abrasive paper of No. 600, with the finality to obtain similar surface to the internal circulation piping nuclear reactor. Oxides was formed within an autoclave (Autoclave MEX-02 unit B), which is a device that simulates the working conditions of the nuclear reactor, but without radiation generated by the fission reaction within the reactor. The oxidation conditions were a temperature of 280 C and pressure of 8 MPa, similar conditions to the reactor operating in nuclear power plant of Laguna Verde in Veracruz, Mexico (BWR conditions), with an average conductivity of 4.58 ms / cm and 2352 ppb oxygen to simulate normal water chemistry NWC. Were obtained deposits of noble metal oxides formed on 304l stainless steel samples, in a 250 ml autoclave at a temperature range of 180 to 200 C. The elements that were used to deposit platinum-rhodium (Pt-Rh) with aqueous Na{sub 2}Pt (OH){sub 6} and Na{sub 3}Rh (NO{sub 2}){sub 6}, Silver (Ag) with an aqueous solution of AgNO{sub 3}, zirconium (Zr) with aqueous Zr O (NO{sub 3}) and ZrO{sub 2}, and zinc (Zn) in aqueous solution of Zn (NO{sub 3}){sub 2} under conditions of normal water chemistry. Also there was the oxidation of 304l stainless steel specimens in normal water chemistry with a solution of Zinc (Zn) (NWC + Zn). Oxidation of the specimens in water chemistry with a solution of zinc (Zn + NWC) was prepared in two ways: within the MEX-02 autoclave unit A in a solution of zinc and a flask at constant temperature in zinc solution. The oxides formed and deposits were characterized by scanning electron microscopy, energy dispersive X-ray analysis, elemental field analysis and X-ray diffraction. By other hand was evaluated the electrochemical behavior of the oxides formed on the surface of 304l stainless steel in normal water chemistry, zirconium deposits on these oxides and deposits formed in a flask at constant temperature in solution of zinc, with power noise technique and electrochemical tafel extrapolation technique. Finally, were presented the results to the nuclear as an alternative mitigation effort stress corrosion cracking (SCC) and thus give support to the nuclear power plant of Laguna Verde in the action of existing corrosion phenomenon. (Author)
Energy Technology Data Exchange (ETDEWEB)
Alonso V, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Torres A, C. [CFE, Veracruz (Mexico)
1991-06-15
In this work in a general way the form in that it was generated the database of the initial fuel load of the Laguna Verde Unit 1 reactor is described. The initial load is formed with fuel of the GE6 type. The obtained results during the formation of the database in as much as to the behavior of the different cell parameters regarding the one burnt of the fuel and the variation of vacuums in the coolant channel its are compared very favorably with those reported by the General Electric fuel supplier and reported in the design documents of the same one. (Author)
International Nuclear Information System (INIS)
Ortega, J.; Marrero, E.; Toledo, F.J.
2006-01-01
In this article, the experimental data of excess molar enthalpies H m E and excess molar volumes V m E are presented for a set of 20 binary mixtures comprised of the first four butyl alkanoates (methanoate to butanoate) and five α,ω-dichloroalkanes (1,2-dichloroethane to 1,6-dichlorohexane), obtained at atmospheric pressure and at a temperature of 298.15K. The results indicate the existence of specific interactions between both kinds of compounds resulting in exothermic processes for most mixtures, except for those containing butyl methanoate which give rise to net endo/exothermic effects. The V m E are positive for mixtures of (butyl esters+1,2-dichloroethane or 1,3-dichloropropane) and negative for the remaining ones. The change in H m E with the dichloroethane chain length for a same ester is regular although the V m E presents an irregular variation. It can, therefore, be deuced from this that the mixing process involves both effects, exothermic/endothermic and expansion/contraction, simultaneously. The behaviour of the mixtures is interpreted on the basis of the results observed and attributed to different effects taking place among the molecules studied. To improve application of the UNIFAC model using the version of Dang and Tassios, average values were recalculated again for parameters of the ester/chloride interaction, distinguishing, during its application, the functional group of the acid part of the ester. In spite of this, the model does not adequately reproduce the systems' behaviour.
Energy Technology Data Exchange (ETDEWEB)
Ruiz E, J.A. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Blazquez M, J. [CIEMAT, 28040 Madrid (Spain)]. e-mail: jare@nuclear.inin.mx
2003-07-01
In this work it is looked for, to calculate the reactivity starting from the measures of the one nuclear detection system denominated by their initials in English 'APRM' (Average Power Range Monitor) of the oscillatory event of the unit 1 of the nuclear power station of Laguna Verde happened the 24/01/1995. The reference signal consists of 3589 points taken every 0.2 seconds before the reactor operator carried out the cut of the same one. It is tried to give answer to queries like: When the event really began?, How distinguishing the stable part of the unstable? Which could be the way of predicting it?. The analysis is developed applying the call 'inverse method', with the purpose of interpreting the power response, having a mean of obtaining the information about the changes of reactivity that were given in the transitory one and to look their relationship with the actions taken by the operator. A comparison of the variation of the signal of reactivity with basic statistical variables with the purpose of trying of to find a mechanism for early detection of the instability is included. (Author)
Energy Technology Data Exchange (ETDEWEB)
Tijerina S, F. [CFE, Central Laguna Verde, Km. 42.5 Carretera Cardel-Nautla, Veracruz (Mexico)]. e-mail: francisco.tijerina@cfe.gob.mx
2008-07-01
The engineers in nuclear power plants BWRs and PWRs based on the development of the ultrasonic technology for the measurement of the mass, volumetric flow, density and temperature in fluids, have applied this technology in two primary targets approved by the NRC: the use for the recovery of thermal power in the reactor and/or to be able to realize an increase of thermal power licensed in a 2% (MUR) by 1OCFR50 Appendix K. The present article mentions the current problem in the measurement of the feedwater flow with Venturi meters, which affects that the thermal balance of reactor BWRs or PWRs this underestimated. One in broad strokes describes the application of the ultrasonic technology for the ultrasonic measurement in the flow of the feedwater system of the reactor and power to recover thermal power of the reactor. One is to the methodology developed in CFE for a calibration of the temperature transmitters of RTD's and the methodology for a calibration of the venturi flow transmitters using ultrasonic measurement. Are show the measurements in the feedwater of reactor of the temperature with RTD's and ultrasonic measurement, as well as the flow with the venturi and the ultrasonic measurement operating the reactor to the 100% of nominal thermal power, before and after the calibration of the temperature transmitters and flow. Finally, is a plan to be able to realize a recovery of thermal power of the reactor, showing as carrying out their estimations. As a result of the application of ultrasonic technology in the feedwater of reactor BWR-5 in Laguna Verde, in the Unit 1 cycle 13 it was recover an equivalent energy to a thermal power of 25 MWt in the reactor and an exit electrical power of 6 M We in the turbogenerator. Also in the Unit 2 cycle 10 it was recover an equivalent energy to a thermal power of 40 MWt in the reactor and an exit electrical power of 16 M We in the turbogenerator. (Author)
Energy Technology Data Exchange (ETDEWEB)
Montes T, J.L.; Cortes C, C.C. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)
1992-08-15
This guide is applied for the reload pattern's formation for mirror symmetry of a core room and in accordance with the Control Cell core technique (of the english Control Cell Core - CCC) for the PRESTO-B code. (Author)
Stepanova, I S; Bogoliubov, D S
2003-01-01
The nuclear distribution of pre-mRNA splicing factors (snRNPs and SR-protein SC35) and unphosphorylated from of RNA polymerase II (Pol II) was studied using fluorescent and immunoelectron cytochemistry in diplotene oocytes of the gastropod Achatina fulica. Association of Pol II and splicing factors with oocyte nuclear structures was analysed. The antibodies against splicing factors and Pol II were shown to label perichromatin fibrils at the periphery of condensed chromatin blocks as well as those in interchromatin regions of nucleoplasm. The revealed character of distribution of snRNPs, SC35 protein, and Pol II, together with the decondensed chromatin and absence of karyosphere, enable us to suggest that oocyte chromosomes maintain their transcriptional activity at the diplotene stage of oogenesis. In A. fulica oocytes, sparse nuclear bodies (NBs) of a complex morphological structure were revealed. These NBs contain snRNPs rather than SC35 protein. NBs are associated with a fibrogranular material (FGM), which contains SC35 protein. No snRNPs were revealed in this material. Homology of A. fulica oocyte nuclear structures to Cajal bodies and interchromatin granule clusters is discussed.
Definition of domain boundaries and crystallization of the SMN Tudor domain
Sprangers, Remco; Selenko, Philipp; Sattler, Michael; Sinning, Irmgard; Groves, Matthew R
Spinal muscular atropy (SMA) is the major genetic disease leading to childhood mortality and is caused by mutations in or deletions of the smn1 gene. The human survival of motor neurons (SMN) protein encoded by this gene plays an important role in the assembly of snRNPs (small nuclear
Energy Technology Data Exchange (ETDEWEB)
Ortega, J. [Laboratorio de Termodinamica y Fisicoquimica de Fluidos, Parque Cientifico-Tecnologico, Campus Universitario Tafira, Universidad de Las Palmas de Gran Canaria, 35071-Las Palmas de Gran Canaria, Canary Islands (Spain)]. E-mail: jortega@dip.ulpgc.es; Marrero, E. [Laboratorio de Termodinamica y Fisicoquimica de Fluidos, Parque Cientifico-Tecnologico, Campus Universitario Tafira, Universidad de Las Palmas de Gran Canaria, 35071-Las Palmas de Gran Canaria, Canary Islands (Spain); Toledo, F.J. [Laboratorio de Termodinamica y Fisicoquimica de Fluidos, Parque Cientifico-Tecnologico, Campus Universitario Tafira, Universidad de Las Palmas de Gran Canaria, 35071-Las Palmas de Gran Canaria, Canary Islands (Spain)
2006-09-15
In this article, the experimental data of excess molar enthalpies H{sub m}{sup E} and excess molar volumes V{sub m}{sup E} are presented for a set of 20 binary mixtures comprised of the first four butyl alkanoates (methanoate to butanoate) and five {alpha},{omega}-dichloroalkanes (1,2-dichloroethane to 1,6-dichlorohexane), obtained at atmospheric pressure and at a temperature of 298.15K. The results indicate the existence of specific interactions between both kinds of compounds resulting in exothermic processes for most mixtures, except for those containing butyl methanoate which give rise to net endo/exothermic effects. The V{sub m}{sup E} are positive for mixtures of (butyl esters+1,2-dichloroethane or 1,3-dichloropropane) and negative for the remaining ones. The change in H{sub m}{sup E} with the dichloroethane chain length for a same ester is regular although the V{sub m}{sup E} presents an irregular variation. It can, therefore, be deuced from this that the mixing process involves both effects, exothermic/endothermic and expansion/contraction, simultaneously. The behaviour of the mixtures is interpreted on the basis of the results observed and attributed to different effects taking place among the molecules studied. To improve application of the UNIFAC model using the version of Dang and Tassios, average values were recalculated again for parameters of the ester/chloride interaction, distinguishing, during its application, the functional group of the acid part of the ester. In spite of this, the model does not adequately reproduce the systems' behaviour.
Energy Technology Data Exchange (ETDEWEB)
Navas, A. [Laboratorio de Termodinamica y Fisicoquimica de Fluidos, Parque Cientifico-Tecnologico, Campus Universitario de Tafira, Universidad de Las Palmas de Gran Canaria, 35071, Las Palmas de Gran Canaria, Canary Islands (Spain); Ortega, J. [Laboratorio de Termodinamica y Fisicoquimica de Fluidos, Parque Cientifico-Tecnologico, Campus Universitario de Tafira, Universidad de Las Palmas de Gran Canaria, 35071, Las Palmas de Gran Canaria, Canary Islands (Spain)], E-mail: jortega@dip.ulpgc.es; Nuez, I. de la [Laboratorio de Termodinamica y Fisicoquimica de Fluidos, Parque Cientifico-Tecnologico, Campus Universitario de Tafira, Universidad de Las Palmas de Gran Canaria, 35071, Las Palmas de Gran Canaria, Canary Islands (Spain)
2009-11-15
This work shows the experimental values obtained for H{sub m}{sup E} and V{sub m}{sup E} at the temperature of 298.15 K and atmospheric pressure, for a set of 20 binary mixtures comprised of the first four butyl esters (methanoate to butanoate) with five {alpha},{omega}-dibromoalkanes (1,2-dibromoethane to 1,6-dibromohexane). The H{sub m}{sup E} are endothermic for mixtures with butyl methanoate, while for the other esters the H{sub m}{sup E} adopt a sigmoidal shape. The V{sub m}{sup E} are positive for mixtures with low molecular weight dibromoalkanes, becoming negative with contractive effects in the final mixture, as the dihalide chain increases. The results indicate that the mixtures present specific interactions, with simultaneous expansion/contraction and exothermic/endothermic effects, and an explanation is given for the different types of interaction taking place. Experimental data are correlated with a polynomial equation used in previous works with satisfactory results. Modelling of the experimental results of the mixtures is carried out on the H{sub m}{sup E} values, giving rise to an adequate definition of the different interactions taking place. Two versions of the UNIFAC method were used, and for Dang and Tassios' version different possibilities were considered for the interaction parameters of the ester (G)/dibromide (G'). The best estimations were obtained when the pair of interaction parameters, type a{sub G/G{sup '}}, depended on the number of carbon atoms in the compounds constituting the mixture.
International Nuclear Information System (INIS)
Alonso V, G.; Torres A, C.
1991-06-01
In this work in a general way the form in that it was generated the database of the initial fuel load of the Laguna Verde Unit 1 reactor is described. The initial load is formed with fuel of the GE6 type. The obtained results during the formation of the database in as much as to the behavior of the different cell parameters regarding the one burnt of the fuel and the variation of vacuums in the coolant channel its are compared very favorably with those reported by the General Electric fuel supplier and reported in the design documents of the same one. (Author)
International Nuclear Information System (INIS)
Dubovik, V.M.; Zenkin, S.V.
1983-01-01
On the basis of the total effective Hamiltonian of the parity nonconserving (PNC) hadron-hadron interactions found within the standard model SU(2)sUb(L)XU(1)xSU(3)sub(c) in all orders of the leading logarithms allowing for the difference of quark mass scales (msub(c)>>msub(u, d, s)) the PNC πNN vertex generating the long-range part of the PNC nuclear forces is considered. The origin and the methods of calculation of various contributions to this vertex with a special attention to possible artifacts of these methods is anatyzed. Within the self-consistence calculational framework partly including the MIT bag model the total value of the constant hsub(π) determining the PNC πNN vertex is evaluated. Value of hsub(π) (approximately 1.3x10 -7 ) is 2-4 times as small as previous estimates and does not contradict the experimental data
International Nuclear Information System (INIS)
Skutlartz, A.; Hagmann, S.; Schmidt-Boecking, H.
1988-01-01
The impact parameter dependence of ECC cusp electron production in collisions of fast, highly charged ions with atoms is investigated by measuring the scattered projectiles in coincidence with cusp electrons emitted at 0 0 with respect to the beam axis. The absolute probabilities for ECC cusp production show a maximum at b ≅ 0.10 au, decrease strongly for smaller impact parameters and more gently toward larger impact parameters. In addition the final charge state of the scattered projectile is also determined simultaneously for each collision event. The probabilities, as a function of the projectile final charge state, are large for the case where at least one or more electrons are simultaneously captured into bound states of the projectile, but are surprisingly small for collisions in which a projectile did not capture an electron into a bound state. (author)
Cakir, P.; Eloirdi, R; Huber, F.; Konings, R.J.M.; Gouder, T
2017-01-01
Thin films of U_{1− x}Th_{x}O_{2} (x = 0 to 1) have been deposited via reactive DC sputter technique and characterized by X-ray/Ultra-violet Photoelectron Spectroscopy (XPS/UPS), X-ray Powder Diffractometer (XRD) and Cyclic Voltammetry (CV) in order to understand the
Scalet, Daniela; Sacchetto, Claudia; Bernardi, Francesco; Pinotti, Mirko; van de Graaf, Stan F. J.; Balestra, Dario
2018-01-01
In tyrosinaemia type 1(HT1), a mosaic pattern of fumarylacetoacetase (FAH) immunopositive or immunonegative nodules in liver tissue has been reported in many patients. This aspect is generally explained by a spontaneous reversion of the mutation into a normal genotype. In one HT1 patient carrying
International Nuclear Information System (INIS)
Navas, A.; Ortega, J.; Nuez, I. de la
2009-01-01
This work shows the experimental values obtained for H m E and V m E at the temperature of 298.15 K and atmospheric pressure, for a set of 20 binary mixtures comprised of the first four butyl esters (methanoate to butanoate) with five α,ω-dibromoalkanes (1,2-dibromoethane to 1,6-dibromohexane). The H m E are endothermic for mixtures with butyl methanoate, while for the other esters the H m E adopt a sigmoidal shape. The V m E are positive for mixtures with low molecular weight dibromoalkanes, becoming negative with contractive effects in the final mixture, as the dihalide chain increases. The results indicate that the mixtures present specific interactions, with simultaneous expansion/contraction and exothermic/endothermic effects, and an explanation is given for the different types of interaction taking place. Experimental data are correlated with a polynomial equation used in previous works with satisfactory results. Modelling of the experimental results of the mixtures is carried out on the H m E values, giving rise to an adequate definition of the different interactions taking place. Two versions of the UNIFAC method were used, and for Dang and Tassios' version different possibilities were considered for the interaction parameters of the ester (G)/dibromide (G'). The best estimations were obtained when the pair of interaction parameters, type a G/G ' , depended on the number of carbon atoms in the compounds constituting the mixture.
International Nuclear Information System (INIS)
Ortega, J.; Marrero, E.; Toledo, F.J.; Espiau, F.
2005-01-01
This article presents the experimental data of H m E and V m E , obtained at atmospheric pressure and at a temperature of 298.15K, for a set of 25 binary mixtures composed of the first 5 ethyl alkanoates (methanoate to pentanoate) and five α,ω-dichloroalkanes (1,2-dichloroethane to 1,6-dichlorohexane). Quantitatively, and with only a few exceptions, small values are obtained for the excess properties and the results imply that specific interactions exist between both types of compounds, with exothermic process for most mixtures, but with the exception of some that contain ethyl methanoate and ethanoate. The change in enthalpies with increasing length of the dichloroalkane chain for the same ester is regular, and also the change in H m E with the acid portion of the ethyl ester. However, the change in excess volumes does not present such a regular variation. A behavioural structural model is established to explain the results of the excess properties. Experimental values of H m E and V m E were correlated, as a function of ester concentration, x with a new expression which uses the so-called active fraction as a variable and which, in turn, is a function of this concentration. The application of two versions of the UNIFAC group contribution models produces no good estimations of H m E .
International Nuclear Information System (INIS)
Ortega, J.; Navas, A.; Placido, J.; Toledo, F.J.
2006-01-01
Excess molar enthalpies H m E , and excess molar volumes V m E , have been determined experimentally at constant conditions of atmospheric pressure and a temperature of T=298.15K, for a set of 25 binary mixtures, composed of ethyl alkanoate (methanoate to pentanoate) with each of the α,ω-dibromoalkanes (1,2-dibromoethane to 1,6-dibromohexane), presenting the values of excess quantities Y m E as a function of the ester composition x. Most of the mixtures presented V m E >0, except those formed by 1,5-dibromopentane and 1,6-dibromohexane with propanoate, butanoate and ethyl pentanoate, for which V m E m E are made using two versions of the UNIFAC group contribution model. The version proposed by Dang and Tassios produces unacceptable estimations, while the version of Gmehling et al. produces results closer to experimentals.
Beattie, Christine E; Kolb, Stephen J
2018-08-15
Spinal muscular atrophy is caused by deletions or mutations in the SMN1 gene that result in reduced expression of the SMN protein. The SMN protein is an essential molecular chaperone that is required for the biogenesis of multiple ribonucleoprotein (RNP) complexes including spliceosomal small nuclear RNPs (snRNPs). Reductions in SMN expression result in a reduced abundance of snRNPs and to downstream RNA splicing alterations. SMN is also present in axons and dendrites and appears to have important roles in the formation of neuronal mRNA-protein complexes during development or neuronal repair. Thus, SMA is an exemplar, selective motor neuron disorder that is caused by defects in fundamental RNA processing events. A detailed molecular understanding of how motor neurons fail, and why other neurons do not, in SMA will yield important principals about motor neuron maintenance and neuronal specificity in neurodegenerative diseases. Copyright © 2018 Elsevier B.V. All rights reserved.
Drosophila SMN complex proteins Gemin2, Gemin3, and Gemin5 are components of U bodies
International Nuclear Information System (INIS)
Cauchi, Ruben J.; Sanchez-Pulido, Luis; Liu, Ji-Long
2010-01-01
Uridine-rich small nuclear ribonucleoproteins (U snRNPs) play key roles in pre-mRNA processing in the nucleus. The assembly of most U snRNPs takes place in the cytoplasm and is facilitated by the survival motor neuron (SMN) complex. Discrete cytoplasmic RNA granules called U bodies have been proposed to be specific sites for snRNP assembly because they contain U snRNPs and SMN. U bodies invariably associate with P bodies, which are involved in mRNA decay and translational control. However, it remains unknown whether other SMN complex proteins also localise to U bodies. In Drosophila there are four SMN complex proteins, namely SMN, Gemin2/CG10419, Gemin3 and Gemin5/Rigor mortis. Drosophila Gemin3 was originally identified as the Drosophila orthologue of human and yeast Dhh1, a component of P bodies. Through an in silico analysis of the DEAD-box RNA helicases we confirmed that Gemin3 is the bona fide Drosophila orthologue of vertebrate Gemin3 whereas the Drosophila orthologue of Dhh1 is Me31B. We then made use of the Drosophila egg chamber as a model system to study the subcellular distribution of the Gemin proteins as well as Me31B. Our cytological investigations show that Gemin2, Gemin3 and Gemin5 colocalise with SMN in U bodies. Although they are excluded from P bodies, as components of U bodies, Gemin2, Gemin3 and Gemin5 are consistently found associated with P bodies, wherein Me31B resides. In addition to a role in snRNP biogenesis, SMN complexes residing in U bodies may also be involved in mRNP assembly and/or transport.
Drosophila SMN complex proteins Gemin2, Gemin3, and Gemin5 are components of U bodies
Energy Technology Data Exchange (ETDEWEB)
Cauchi, Ruben J.; Sanchez-Pulido, Luis [MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX (United Kingdom); Liu, Ji-Long, E-mail: jilong.liu@dpag.ox.ac.uk [MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX (United Kingdom)
2010-08-15
Uridine-rich small nuclear ribonucleoproteins (U snRNPs) play key roles in pre-mRNA processing in the nucleus. The assembly of most U snRNPs takes place in the cytoplasm and is facilitated by the survival motor neuron (SMN) complex. Discrete cytoplasmic RNA granules called U bodies have been proposed to be specific sites for snRNP assembly because they contain U snRNPs and SMN. U bodies invariably associate with P bodies, which are involved in mRNA decay and translational control. However, it remains unknown whether other SMN complex proteins also localise to U bodies. In Drosophila there are four SMN complex proteins, namely SMN, Gemin2/CG10419, Gemin3 and Gemin5/Rigor mortis. Drosophila Gemin3 was originally identified as the Drosophila orthologue of human and yeast Dhh1, a component of P bodies. Through an in silico analysis of the DEAD-box RNA helicases we confirmed that Gemin3 is the bona fide Drosophila orthologue of vertebrate Gemin3 whereas the Drosophila orthologue of Dhh1 is Me31B. We then made use of the Drosophila egg chamber as a model system to study the subcellular distribution of the Gemin proteins as well as Me31B. Our cytological investigations show that Gemin2, Gemin3 and Gemin5 colocalise with SMN in U bodies. Although they are excluded from P bodies, as components of U bodies, Gemin2, Gemin3 and Gemin5 are consistently found associated with P bodies, wherein Me31B resides. In addition to a role in snRNP biogenesis, SMN complexes residing in U bodies may also be involved in mRNP assembly and/or transport.
Assembly of the U5 snRNP component PRPF8 is controlled by the HSP90/R2TP chaperones
Czech Academy of Sciences Publication Activity Database
Malinová, Anna; Cvačková, Zuzana; Matějů, Daniel; Hořejší, Zuzana; Abeza, C.; Vandermoere, F.; Bertrand, E.; Staněk, David; Verheggen, C.
2017-01-01
Roč. 216, č. 6 (2017), s. 1579-1596 ISSN 0021-9525 R&D Projects: GA ČR GPP301/12/P425; GA ČR GA15-00790S; GA ČR(CZ) GA14-34264S; GA MŠk LO1419 Institutional support: RVO:68378050 Keywords : dominant retinitis-pigmentosa * splicing factor prp8 * rna-polymerase-ii * structural basis * spliceosomal snrnps * coiled bodies * cajal bodies * r2tp complex * mutations * biogenesis Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 7.955, year: 2016
The Role of Nuclear Bodies in Gene Expression and Disease
Morimoto, Marie; Boerkoel, Cornelius F.
2013-01-01
This review summarizes the current understanding of the role of nuclear bodies in regulating gene expression. The compartmentalization of cellular processes, such as ribosome biogenesis, RNA processing, cellular response to stress, transcription, modification and assembly of spliceosomal snRNPs, histone gene synthesis and nuclear RNA retention, has significant implications for gene regulation. These functional nuclear domains include the nucleolus, nuclear speckle, nuclear stress body, transcription factory, Cajal body, Gemini of Cajal body, histone locus body and paraspeckle. We herein review the roles of nuclear bodies in regulating gene expression and their relation to human health and disease. PMID:24040563
Energy Technology Data Exchange (ETDEWEB)
Diaz, A.; Mendoza, G.; Arganis, C.; Viais, J.; Contreras, A. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Fernandez, G.; Medina, G., E-mail: angeles.diaz@inin.gob.mx [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verde, Carretera Cardel-Nautla Km 42.5, Alto Lucero, Veracruz (Mexico)
2012-10-15
In December of 1991, the US National Regulatory Commission (US NRC) published the 10 Cfr-54, to establish the procedures, criterions and necessary requirements for the license renovation of a nuclear power station. In 1994 the US NRC proposed an amendment to these requirements that basically were centered in the effects of the aging in structures and passive components of long life and in the inclusion of Time Limited Aging Analyses (TLAAs). In a general way, is established that the requester should show to the regulator body that the effects of the aging in structures, systems and components are and will be appropriately negotiated or that the TLAAs has been evaluated for the operation extended period. The NEI 95-10 is a guide document developed by the Nuclear Energy Institute (NEI), to provide a focus accepted to cover the requirements of 10 Cfr-54, offering an efficient process that allows to any requester to complete in a practical way the requirements of the License Renovation Rule and to supplement their solicitude. This work presents the application of this guide to the Reactor Core Insulation Cooling (Rcic) of the Unit 1 of the nuclear power plant of Laguna Verde, elect as pilot system to carry out the application of the 10 Cfr-54 following the recommended methodology by the Industrial Guide for the implementation of the License Renovation Rule. (Author)
Energy Technology Data Exchange (ETDEWEB)
Montes, J.L.; Perusquia, R.; Ortiz, J.J.; Hernandez, J.L.; Ramirez, J.R. [ININ, Carretera Mexico-Toluca Km. 36.5, 52045 Estado de Mexico (Mexico)]. e-mail: jlmt@nuclear.inin.mx
2004-07-01
In recent dates the Laguna Verde Nuclear Power station (CNLV) has acquired new designs of control bars, this new type of bars presents modifications important in their design. For what is important to analyze their performance inside those reactors of this nuclear power station. Presently work is shown the behavior of the nucleus of the reactor in hot condition (HFP) when three different types of control bar are used. The first of them corresponds the one that initially has been used in this power station and that we will call original. The second type of control bars, it corresponds to an advanced type and it is the first design different from the original and it corresponds to a bar design that it includes Hafnium (Hf) like one of their neutronic absorption characteristics. The third, denoted as 2AV, include besides the material of the second type new design characteristics, and it is the last finish bar type that it has been introduced in the operation of the reactors of the CNLV. With base in the studied cases is found that the bars 2AV have a total power value, 7.6 % bigger respect the bars 1AV; and in turn the bars 1AV, 6.1 % bigger with respect the ORG control bars. (Author)
Gemin5: A Multitasking RNA-Binding Protein Involved in Translation Control
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David Piñeiro
2015-04-01
Full Text Available Gemin5 is a RNA-binding protein (RBP that was first identified as a peripheral component of the survival of motor neurons (SMN complex. This predominantly cytoplasmic protein recognises the small nuclear RNAs (snRNAs through its WD repeat domains, allowing assembly of the SMN complex into small nuclear ribonucleoproteins (snRNPs. Additionally, the amino-terminal end of the protein has been reported to possess cap-binding capacity and to interact with the eukaryotic initiation factor 4E (eIF4E. Gemin5 was also shown to downregulate translation, to be a substrate of the picornavirus L protease and to interact with viral internal ribosome entry site (IRES elements via a bipartite non-canonical RNA-binding site located at its carboxy-terminal end. These features link Gemin5 with translation control events. Thus, beyond its role in snRNPs biogenesis, Gemin5 appears to be a multitasking protein cooperating in various RNA-guided processes. In this review, we will summarise current knowledge of Gemin5 functions. We will discuss the involvement of the protein on translation control and propose a model to explain how the proteolysis fragments of this RBP in picornavirus-infected cells could modulate protein synthesis.
Goncharov, I; Palfi, Z; Bindereif, A; Michaeli, S
1999-04-30
Trans-splicing in trypanosomes involves the addition of a common spliced leader (SL) sequence, which is derived from a small RNA, the SL RNA, to all mRNA precursors. The SL RNA is present in the cell in the form of a ribonucleoprotein, the SL RNP. Using conventional chromatography and affinity selection with 2'-O-methylated RNA oligonucleotides at high ionic strength, five proteins of 70, 16, 13, 12, and 8 kDa were co-selected with the SL RNA from Leptomonas collosoma, representing the SL RNP core particle. Under conditions of lower ionic strength, additional proteins of 28 and 20 kDa were revealed. On the basis of peptide sequences, the gene coding for a protein with a predicted molecular weight of 11.9 kDa was cloned and identified as homologue of the cis-spliceosomal SmE. The protein carries the Sm motifs 1 and 2 characteristic of Sm antigens that bind to all known cis-spliceosomal uridylic acid-rich small nuclear RNAs (U snRNAs), suggesting the existence of Sm proteins in trypanosomes. This finding is of special interest because trypanosome snRNPs are the only snRNPs examined to date that are not recognized by anti-Sm antibodies. Because of the early divergence of trypanosomes from the eukaryotic lineage, the trypanosome SmE protein represents one of the primordial Sm proteins in nature.
Harmonic superspaces of extended supersymmetry
International Nuclear Information System (INIS)
Ivanov, E.; Kalitzin, S.; Nguyen Ai Viet; Ogievetsky, V.
1984-01-01
The main technical apparatus of the harmonic superspace approach to extended SUSY, the calculus of harmonic variables on homogeneous spaces of the SUSY automorphism groups, is presented in detail for N=2, 3, 4. The basic harmonics for the coset manifolds G/H with G=SU(2), H=U(1); G=SU(3), H=SU(2)xU(1) and H=U(1)xU(1); G=SU(4), H=SU(3)xU(1), H=SU(2)xSU(2)xU(1), H=SU(2)xU(1)xU(1) and H=U(1)xU(1)xU(1); G=USp(2), H=SU(2)xSU(2), H=SU(2)xU(1) and H=U(1)xU(1) are tabulated a number of useful relations among them
Directory of Open Access Journals (Sweden)
Hani Kotzer-Nevo
2014-06-01
Full Text Available When isolated from mammalian cell nuclei, all nuclear pre-mRNAs are packaged in multi-subunit large ribonucleoprotein complexes—supraspliceosomes—composed of four native spliceosomes interconnected by the pre-mRNA. Supraspliceosomes contain all five spliceosomal U snRNPs, together with other splicing factors, and are functional in splicing. Supraspliceosomes studied thus far represent the steady-state population of nuclear pre-mRNAs that were isolated at different stages of the splicing reaction. To analyze specific splicing complexes, here, we affinity purified Pseudomonas aeruginosa phage 7 (PP7-tagged splicing complexes assembled in vivo on Adenovirus Major Late (AdML transcripts at specific functional stages, and characterized them using molecular techniques including mass spectrometry. First, we show that these affinity purified splicing complexes assembled on PP7-tagged AdML mRNA or on PP7-tagged AdML pre-mRNA are assembled in supraspliceosomes. Second, similar to the general population of supraspliceosomes, these defined supraspliceosomes populations are assembled with all five U snRNPs at all splicing stages. This study shows that dynamic changes in base-pairing interactions of U snRNA:U snRNA and U snRNA:pre-mRNA that occur in vivo during the splicing reaction do not require changes in U snRNP composition of the supraspliceosome. Furthermore, there is no need to reassemble a native spliceosome for the splicing of each intron, and rearrangements of the interactions will suffice.
Chaly, N; Cadrin, M; Kaplan, J G; Brown, D L
1988-01-01
Assembly of active nuclei in lymphocytes stimulated by mitogen is paralleled by the elaboration of a structurally and biochemically complex nuclear matrix (NM). To examine the dynamics of individual NM polypeptide components during blastogenesis, we have applied immunofluorescence labelling with anti-NM antibodies to concanavalin A-stimulated mouse splenocytes. Whereas peripherin and PI2 antigens did not reorganize during stimulation, labelling of PI1 and small nuclear ribonucleoprotein (snRNP) antigens increased markedly in intensity and redistributed in concert with the previously reported NM restructuring. Double-labelling showed, furthermore, that snRNPs and the internal staining component of PI1 were largely co-localized. As an approach to studying the role of RNA and RNA synthesis in NM organization, we have further examined the effects of the inhibitor of RNA synthesis, 5,6-dichloro-1-beta-D-ribofuranosyl benzimidazole (DRB), on NM antigen distribution. The rapid inhibition of 3H-uridine incorporation by DRB was accompanied by coordinate aggregation of snRNPs and of the internal PI1 component into large, brightly stained patches. Both 3H-uridine incorporation levels and antigen localization were readily reversed upon removal of DRB. We conclude that NM antigens behave independently during nuclear and NM assembly and that NM organization, as reflected by NM antigen distribution, is modulated by con A- and DRB-induced alterations in RNA synthesis. We propose, furthermore, that the PI1 antigen plays a role in RNA metabolism, and is possibly involved in RNA transport to the nuclear periphery.
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Shuaiyang Zhao
2017-10-01
Full Text Available Abstract Background Theileria annulata can infect monocytes/macrophages and B lymphocytes and causes severe lymphoproliferative disease in ruminants. Meanwhile, infection by T. annulata leads to the permanent proliferation of cell population through regulating signaling pathways of host cells. Cysteine proteinases (CPs are one kind of protein hydrolase and usually play critical roles in parasite virulence, host invasion, nutrition and host immune response. However, the biological function of T. annulata CP (TaCP is still unclear. In this study, a yeast-two-hybrid assay was performed to screen host proteins interacting with TaCP, to provide information to help our understanding of the molecular mechanisms between T. annulata and host cells. Methods The cDNA from purified bovine B cells was inserted into pGADT7-SfiI vector (pGADT7-SfiI-BcDNA, Prey plasmid for constructing the yeast two-hybrid cDNA library. TaCP was cloned into the pGBKT7 vector (pGBKT7-TaCP and was considered as bait plasmid after evaluating the expression, auto-activation and toxicity tests in the yeast strain Y2HGold. The yeast two-hybrid screening was carried out via co-transforming bait and prey plasmids into yeast strain Y2HGold. Sequences of positive preys were analyzed using BLAST, Gene Ontology, UniProt and STRING. Results Two host proteins, CRBN (Bos taurus cereblon transcript variant X2 and Ppp4C (Bos indicus protein phosphatase 4 catalytic subunit were identified to interact with TaCP. The results of functional analysis showed that the two proteins were involved in many cellular processes, such as ubiquitylation regulation, microtubule organization, DNA repair, cell apoptosis and maturation of spliceosomal snRNPs. Conclusions This study is the first to screen the host proteins of bovine B cells interacting with TaCP, and 2 proteins, CRBN and Ppp4C, were identified using yeast two-hybrid technique. The results of functional analysis suggest that the two proteins are
Czech Academy of Sciences Publication Activity Database
Chen, S.-Ch.; Tsai, Ch.-J.; Huang, Ch.-Y.; Chen, H.-D.; Chen, S.-J.; Lin, Ch.-Ch.; Tsai, J.-H.; Chou, Ch.C.K.; Lung, S.-Ch.; Huang, W.-R.; Smolík, Jiří; Ondráčková, Lucie
2010-01-01
Roč. 44, č. 9 (2010), s. 713-723 ISSN 0278-6826 Grant - others:EPA(TW) 96-U1U1-02-104; EPA(TW) 97-U1U1-02-106 Institutional research plan: CEZ:AV0Z40720504 Keywords : artifact * aerosol characterization * mass closure Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.340, year: 2010
N=3 and N=4 superconformal WZNW sigma models in superspace. Part 1
International Nuclear Information System (INIS)
Ivanov, E.A.; Krivonos, S.O.
1989-01-01
A manifestly invariant superfield description of N=3 and N=4 2D superconformal WZNW sigma models with U(1)xO(3) and U(1)xUO(4) as the bosonic target manifolds. We construct the N=3 superspace formulation of the U(1)xO(3) model. The self-contained definition of N=3 supercurrent via the basic U(1)xO(3) model. 23 refs
The recruitment of the U5 snRNP to nascent transcripts requires internal loop 1 of U5 snRNA.
Kim, Rebecca; Paschedag, Joshua; Novikova, Natalya; Bellini, Michel
2012-12-01
In this study, we take advantage of the high spatial resolution offered by the nucleus and lampbrush chromosomes of the amphibian oocyte to investigate the mechanisms that regulate the intranuclear trafficking of the U5 snRNP and its recruitment to nascent transcripts. We monitor the fate of newly assembled fluorescent U5 snRNP in Xenopus oocytes depleted of U4 and/or U6 snRNAs and demonstrate that the U4/U6.U5 tri-snRNP is not required for the association of U5 snRNP with Cajal bodies, splicing speckles, and nascent transcripts. In addition, using a mutational analysis, we show that a non-functional U5 snRNP can associate with nascent transcripts, and we further characterize internal loop structure 1 of U5 snRNA as a critical element for licensing U5 snRNP to target both nascent transcripts and splicing speckles. Collectively, our data support the model where the recruitment of snRNPs onto pre-mRNAs is independent of spliceosome assembly and suggest that U5 snRNP may promote the association of the U4/U6.U5 tri-snRNP with nascent transcripts.
Assembly and breakdown of Cajal bodies in accessory nuclei of Hymenoptera.
Jaglarz, Mariusz K; Bilinski, Szczepan M; Kloc, Malgorzata
2005-03-01
In some species of insects, oocytes have vesicular organelles, termed accessory nuclei (ANs). The ANs form by budding off from the nuclear envelope of the oocyte and are filled with translucent matrix containing dense inclusions. One type of these inclusions contains coilin and small nuclear ribonucleoproteins (snRNPs) and is homologous to Cajal bodies. We describe the early events in the morphogenesis of Cajal bodies in the ANs (ANCBs) of the common wasp, Vespula germanica, and show that they contain survival of motor neurons (SMN) protein. We present evidence that in the wasp, ANCBs form by the gradual accumulation of aggregates composed of SMN and small nuclear RNAs. We also show that ANCBs break down and disperse within the ANs as the ANs, which initially surround the oocyte nucleus, localize to the oocyte cortex. The components of dispersed ANCBs are retained within ANs until the end of oogenesis, which suggests that their function may be required at the onset of embryonic development. Because the morphology and behavior of ANs and their Cajal body-like inclusions are conserved in two other hymenopteran species, these features might be characteristic of all hymenopterans.
How do SMA-linked mutations of SMN1 lead to structural/functional deficiency of the SMA protein?
Directory of Open Access Journals (Sweden)
Wei Li
Full Text Available Spinal muscular atrophy (SMA is an autosomal recessive neuromuscular disease with dysfunctional α-motor neurons in the anterior horn of the spinal cord. SMA is caused by loss (∼95% of SMA cases or mutation (∼5% of SMA cases of the survival motor neuron 1 gene SMN1. As the product of SMN1, SMN is a component of the SMN complex, and is also involved in the biosynthesis of the small nuclear ribonucleoproteins (snRNPs, which play critical roles in pre-mRNA splicing in the pathogenesis of SMA. To investigate how SMA-linked mutations of SMN1 lead to structural/functional deficiency of SMN, a set of computational analysis of SMN-related structures were conducted and are described in this article. Of extraordinary interest, the structural analysis highlights three SMN residues (Asp44, Glu134 and Gln136 with SMA-linked missense mutations, which cause disruptions of electrostatic interactions for Asp44, Glu134 and Gln136, and result in three functionally deficient SMA-linked SMN mutants, Asp44Val, Glu134Lys and Gln136Glu. From the computational analysis, it is also possible that SMN's Lys45 and Asp36 act as two electrostatic clips at the SMN-Gemin2 complex structure interface.
Knocking Down Snrnp200 Initiates Demorphogenesis of Rod Photoreceptors in Zebrafish
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Yuan Liu
2015-01-01
Full Text Available Purpose. The small nuclear ribonucleoprotein 200 kDa (SNRNP200 gene is a fundamental component for precursor message RNA (pre-mRNA splicing and has been implicated in the etiology of autosomal dominant retinitis pigmentosa (adRP. This study aims to determine the consequences of knocking down Snrnp200 in zebrafish. Methods. Expression of the Snrnp200 transcript in zebrafish was determined via whole mount in situ hybridization. Morpholino oligonucleotide (MO aiming to knock down the expression of Snrnp200 was injected into zebrafish embryos, followed by analyses of aberrant splicing and expression of the U4/U6-U5 tri-small nuclear ribonucleoproteins (snRNPs components and retina-specific transcripts. Systemic changes and retinal phenotypes were further characterized by histological study and immunofluorescence staining. Results. Snrnp200 was ubiquitously expressed in zebrafish. Knocking down Snrnp200 in zebrafish triggered aberrant splicing of the cbln1 gene, upregulation of other U4/U6-U5 tri-snRNP components, and downregulation of a panel of retina-specific transcripts. Systemic defects were found correlated with knockdown of Snrnp200 in zebrafish. Only demorphogenesis of rod photoreceptors was detected in the initial stage, mimicking the disease characteristics of RP. Conclusions. We conclude that knocking down Snrnp200 in zebrafish could alter regular splicing and expression of a panel of genes, which may eventually trigger rod defects.
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Aaron R. Poole
2017-09-01
Full Text Available Many ribonucleoproteins (RNPs, which are comprised of noncoding RNA and associated proteins, are involved in essential cellular processes such as translation and pre-mRNA splicing. One class of RNP is the small Cajal body-specific RNP (scaRNP, which contributes to the biogenesis of small nuclear RNPs (snRNPs that are central components of the spliceosome. Three scaRNAs are internally processed, generating stable nucleolus-enriched RNAs of unknown function. Here, we provide data that show that these RNAs become part of RNPs we term regulatory RNPs (regRNPs. Most modifications within rRNA (predominantly pseudouridylation and ribose 2′-O-methylation are conducted by small nucleolar RNPs (snoRNPs, and we provide evidence that the activity of at least some of these snoRNPs is under the control of regRNPs. Because modifications within rRNA can vary in different physiological or pathological situations, rRNA modifications are thought to be the major source of ribosome heterogeneity. Our identification of regRNPs thus provides a potential mechanism for how ribosome heterogeneity may be accomplished. This work also provides additional functional connections between the Cajal body and the nucleolus.
U bodies respond to nutrient stress in Drosophila
International Nuclear Information System (INIS)
Buckingham, Mickey; Liu, Ji-Long
2011-01-01
The neurodegenerative disease spinal muscular atrophy (SMA) is caused by mutation of the survival motor neuron 1 (SMN1) gene. Cytoplasmic SMN protein-containing granules, known as U snRNP bodies (U bodies), are thought to be responsible for the assembly and storage of small nuclear ribonucleoproteins (snRNPs) which are essential for pre-mRNA splicing. U bodies exhibit close association with cytoplasmic processing bodies (P bodies), which are involved in mRNA decay and translational repression. The close association of the U body and P body in Drosophila resemble that of the stress granule and P body in yeast and mammalian cells. However, it is unknown whether the U body is responsive to any stress. Using Drosophila oogenesis as a model, here we show that U bodies increase in size following nutritional deprivation. Despite nutritional stress, U bodies maintain their close association with P bodies. Our results show that U bodies are responsive to nutrition changes, presumably through the U body–P body pathway.
Environment-dependent regulation of spliceosome activity by the LSM2-8 complex in Arabidopsis.
Carrasco-López, Cristian; Hernández-Verdeja, Tamara; Perea-Resa, Carlos; Abia, David; Catalá, Rafael; Salinas, Julio
2017-07-07
Spliceosome activity is tightly regulated to ensure adequate splicing in response to internal and external cues. It has been suggested that core components of the spliceosome, such as the snRNPs, would participate in the control of its activity. The experimental indications supporting this proposition, however, remain scarce, and the operating mechanisms poorly understood. Here, we present genetic and molecular evidence demonstrating that the LSM2-8 complex, the protein moiety of the U6 snRNP, regulates the spliceosome activity in Arabidopsis, and that this regulation is controlled by the environmental conditions. Our results show that the complex ensures the efficiency and accuracy of constitutive and alternative splicing of selected pre-mRNAs, depending on the conditions. Moreover, miss-splicing of most targeted pre-mRNAs leads to the generation of nonsense mediated decay signatures, indicating that the LSM2-8 complex also guarantees adequate levels of the corresponding functional transcripts. Interestingly, the selective role of the complex has relevant physiological implications since it is required for adequate plant adaptation to abiotic stresses. These findings unveil an unanticipated function for the LSM2-8 complex that represents a new layer of posttranscriptional regulation in response to external stimuli in eukaryotes. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.
Energy Technology Data Exchange (ETDEWEB)
Hu, Yi, E-mail: yihooyi@gmail.com; Ericsson, Ida, E-mail: ida.ericsson@ntnu.no; Doseth, Berit, E-mail: berit.doseth@ntnu.no; Liabakk, Nina B., E-mail: nina.beate.liabakk@ntnu.no; Krokan, Hans E., E-mail: hans.krokan@ntnu.no; Kavli, Bodil, E-mail: bodil.kavli@ntnu.no
2014-03-10
Activation-induced cytidine deaminase (AID) is the mutator enzyme in adaptive immunity. AID initiates the antibody diversification processes in activated B cells by deaminating cytosine to uracil in immunoglobulin genes. To some extent other genes are also targeted, which may lead to genome instability and B cell malignancy. Thus, it is crucial to understand its targeting and regulation mechanisms. AID is regulated at several levels including subcellular compartmentalization. However, the complex nuclear distribution and trafficking of AID has not been studied in detail previously. In this work, we examined the subnuclear localization of AID and its interaction partner CTNNBL1 and found that they associate with spliceosome-associated structures including Cajal bodies and nuclear speckles. Moreover, protein kinase A (PKA), which activates AID by phosphorylation at Ser38, is present together with AID in nuclear speckles. Importantly, we demonstrate that AID physically associates with the major spliceosome subunits (small nuclear ribonucleoproteins, snRNPs), as well as other essential splicing components, in addition to the transcription machinery. Based on our findings and the literature, we suggest a transcription-coupled splicing-associated model for AID targeting and activation. - Highlights: • AID and its interaction partner CTNNBL1 localize to Cajal bodies and nuclear speckles. • AID associates with its activating kinase PKA in nuclear speckles. • AID is linked to the splicing machinery in switching B-cells. • Our findings suggest a transcription-coupled splicing associated mechanism for AID targeting and activation.
Spliceosome integrity is defective in the motor neuron diseases ALS and SMA
Tsuiji, Hitomi; Iguchi, Yohei; Furuya, Asako; Kataoka, Ayane; Hatsuta, Hiroyuki; Atsuta, Naoki; Tanaka, Fumiaki; Hashizume, Yoshio; Akatsu, Hiroyasu; Murayama, Shigeo; Sobue, Gen; Yamanaka, Koji
2013-01-01
Two motor neuron diseases, amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA), are caused by distinct genes involved in RNA metabolism, TDP-43 and FUS/TLS, and SMN, respectively. However, whether there is a shared defective mechanism in RNA metabolism common to these two diseases remains unclear. Here, we show that TDP-43 and FUS/TLS localize in nuclear Gems through an association with SMN, and that all three proteins function in spliceosome maintenance. We also show that in ALS, Gems are lost, U snRNA levels are up-regulated and spliceosomal U snRNPs abnormally and extensively accumulate in motor neuron nuclei, but not in the temporal lobe of FTLD with TDP-43 pathology. This aberrant accumulation of U snRNAs in ALS motor neurons is in direct contrast to SMA motor neurons, which show reduced amounts of U snRNAs, while both have defects in the spliceosome. These findings indicate that a profound loss of spliceosome integrity is a critical mechanism common to neurodegeneration in ALS and SMA, and may explain cell-type specific vulnerability of motor neurons. PMID:23255347
Coilin phosphorylation mediates interaction with SMN and SmB′
Toyota, Cory G.; Davis, Misty D.; Cosman, Angela M.; Hebert, Michael D.
2010-01-01
Cajal bodies (CBs) are subnuclear domains that participate in spliceosomal small nuclear ribonucleoprotein (snRNP) biogenesis and play a part in the assembly of the spliceosomal complex. The CB marker protein, coilin, interacts with survival of motor neuron (SMN) and Sm proteins. Several coilin phosphoresidues have been identified by mass spectrometric analysis. Phosphorylation of coilin affects its self-interaction and localization in the nucleus. We hypothesize that coilin phosphorylation also impacts its binding to SMN and Sm proteins. In vitro binding studies with a C-terminal fragment of coilin and corresponding phosphomimics show that SMN binds preferentially to dephosphorylated analogs and that SmB′ binds preferentially to phosphomimetic constructs. Bacterially expressed full-length coilin binds more SMN and SmB′ than does the C-terminal fragment. Co-immunoprecipitation and phosphatase experiments show that SMN also binds dephosphorylated coilin in vivo. These data show that phosphorylation of coilin influences interaction with its target proteins and, thus, may be significant in managing the flow of snRNPs through the CB. PMID:19997741
Coilin phosphorylation mediates interaction with SMN and SmB'.
Toyota, Cory G; Davis, Misty D; Cosman, Angela M; Hebert, Michael D
2010-04-01
Cajal bodies (CBs) are subnuclear domains that participate in spliceosomal small nuclear ribonucleoprotein (snRNP) biogenesis and play a part in the assembly of the spliceosomal complex. The CB marker protein, coilin, interacts with survival of motor neuron (SMN) and Sm proteins. Several coilin phosphoresidues have been identified by mass spectrometric analysis. Phosphorylation of coilin affects its self-interaction and localization in the nucleus. We hypothesize that coilin phosphorylation also impacts its binding to SMN and Sm proteins. In vitro binding studies with a C-terminal fragment of coilin and corresponding phosphomimics show that SMN binds preferentially to dephosphorylated analogs and that SmB' binds preferentially to phosphomimetic constructs. Bacterially expressed full-length coilin binds more SMN and SmB' than does the C-terminal fragment. Co-immunoprecipitation and phosphatase experiments show that SMN also binds dephosphorylated coilin in vivo. These data show that phosphorylation of coilin influences interaction with its target proteins and, thus, may be significant in managing the flow of snRNPs through the CB.
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Masaki Kobayashi
2017-03-01
Full Text Available Unique deficits in the function of adult sensory neurons as part of their early neurodegeneration might account for progressive polyneuropathy during chronic diabetes mellitus. Here, we provide structural and functional evidence for aberrant pre-mRNA splicing in a chronic type 1 model of experimental diabetic polyneuropathy (DPN. Cajal bodies (CBs, unique nuclear substructures involved in RNA splicing, increased in number in diabetic sensory neurons, but their expected colocalization with survival motor neuron (SMN proteins was reduced – a mislocalization described in motor neurons of spinal muscular atrophy. Small nuclear ribonucleoprotein particles (snRNPs, also participants in the spliceosome, had abnormal multiple nuclear foci unassociated with CBs, and their associated snRNAs were reduced. CWC22, a key spliceosome protein, was aberrantly upregulated in diabetic dorsal root ganglia (DRG, and impaired neuronal function. CWC22 attenuated sensory neuron plasticity, with knockdown in vitro enhancing their neurite outgrowth. Further, axonal delivery of CWC22 siRNA unilaterally to locally knock down the aberrant protein in diabetic nerves improved aspects of sensory function in diabetic mice. Collectively, our findings identify subtle but significant alterations in spliceosome structure and function, including dysregulated CBs and CWC22 overexpression, in diabetic sensory neurons that offer new ideas regarding diabetic sensory neurodegeneration in polyneuropathy.
Immunoelectron microscopic characterization of nucleolus-associated domains during hibernation.
Malatesta, Manuela; Zancanaro, Carlo; Biggiogera, Marco
2011-01-01
The nucleolus represents a highly dynamic nuclear compartment involved in multiple functions and able to promptly respond to variations of metabolic needs. In the hibernator dormouse, which drastically modifies its metabolic activity during the seasonal cycle, the nucleolus undergoes structural and molecular changes during the torpor bouts; in particular, it shows many nucleoplasmic invaginations containing weakly contrasted areas of unknown nature. To analyze the molecular composition of these nucleolus-associated domains (NADs) and to understand their functional significance, the fine nucleolar composition has been investigated by means of ultrastructural immunocytochemistry in different tissues of euthermic, hibernating, and arousing hazel dormice (Muscardinus avellanarius): in particular, the intranucleolar location of several protein factors involved in the transcription and processing of either pre-rRNA or pre-mRNA has been considered. NADs proved to form during hibernation and disappear upon arousal and were found to contain m₃-G-capped snRNAs, snRNPs, hnRNPs, and the survival motor neuron protein; they were, on the contrary, devoid of the nucleolar factors tested (polymerase I, fibrillarin, nucleolin, and the ribosomal phosphoproteins P₀, P₁, and P₂). We hypothesize that NADs may represent a transient storage site for those molecules involved in the pre-mRNA splicing, which usually transit through the nucleolus; upon arousal, this would facilitate the resumption of RNA maturation by promoting the rapid reactivation of the molecular trafficking from the nucleolus. © 2010 Wiley-Liss, Inc.
U bodies respond to nutrient stress in Drosophila
Energy Technology Data Exchange (ETDEWEB)
Buckingham, Mickey; Liu, Ji-Long, E-mail: jilong.liu@dpag.ox.ac.uk
2011-12-10
The neurodegenerative disease spinal muscular atrophy (SMA) is caused by mutation of the survival motor neuron 1 (SMN1) gene. Cytoplasmic SMN protein-containing granules, known as U snRNP bodies (U bodies), are thought to be responsible for the assembly and storage of small nuclear ribonucleoproteins (snRNPs) which are essential for pre-mRNA splicing. U bodies exhibit close association with cytoplasmic processing bodies (P bodies), which are involved in mRNA decay and translational repression. The close association of the U body and P body in Drosophila resemble that of the stress granule and P body in yeast and mammalian cells. However, it is unknown whether the U body is responsive to any stress. Using Drosophila oogenesis as a model, here we show that U bodies increase in size following nutritional deprivation. Despite nutritional stress, U bodies maintain their close association with P bodies. Our results show that U bodies are responsive to nutrition changes, presumably through the U body-P body pathway.
A new role for FBP21 as regulator of Brr2 helicase activity.
Henning, Lisa M; Santos, Karine F; Sticht, Jana; Jehle, Stefanie; Lee, Chung-Tien; Wittwer, Malte; Urlaub, Henning; Stelzl, Ulrich; Wahl, Markus C; Freund, Christian
2017-07-27
Splicing of eukaryotic pre-mRNA is carried out by the spliceosome, which assembles stepwise on each splicing substrate. This requires the concerted action of snRNPs and non-snRNP accessory proteins, the functions of which are often not well understood. Of special interest are B complex factors that enter the spliceosome prior to catalytic activation and may alter splicing kinetics and splice site selection. One of these proteins is FBP21, for which we identified several spliceosomal binding partners in a yeast-two-hybrid screen, among them the RNA helicase Brr2. Biochemical and biophysical analyses revealed that an intrinsically disordered region of FBP21 binds to an extended surface of the C-terminal Sec63 unit of Brr2. Additional contacts in the C-terminal helicase cassette are required for allosteric inhibition of Brr2 helicase activity. Furthermore, the direct interaction between FBP21 and the U4/U6 di-snRNA was found to reduce the pool of unwound U4/U6 di-snRNA. Our results suggest FBP21 as a novel key player in the regulation of Brr2. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.
Splicing of a C. elegans myosin pre-mRNA in a human nuclear extract
Energy Technology Data Exchange (ETDEWEB)
Ogg, S C; Anderson, P; Wickens, M P [Univ. of Wisconsin, Madison (USA)
1990-01-11
Splicing of mammalian introns requires that the intron possess at least 80 nucleotides. This length requirement presumably reflects the constraints of accommodating multiple snRNPs simultaneously in the same intro. In the free-living nematode, C. elegans, introns typically are 45 to 55 nucleotides in length. In this report, the authors determine whether C. elegans introns can obviate the mammalian length requirement by virtue of their structure or sequence. They demonstrate that a 53 nucleotide intron from the unc-54 gene of C. elegans does not undergo splicing in a mammalian (HeLa) nuclear extract. However, insertion of 31 nucleotides of foreign, prokaryotic sequence into the same intron results in efficient splicing. The observed splicing proceeds by the same two-step mechanism observed with mammalian introns, and exploits the same 3{prime} and 5{prime} sites as are used in C. elegans. The branch point used lies in the inserted sequences. They conclude that C. elegans splicing components are either fewer in number or smaller than their mammalian counterparts.
Multivariate Regression of Liver on Intestine of Mice: A ...
African Journals Online (AJOL)
FIRST LADY
pairs recovered. Linear, semi-logarithmic and logarithmic-logarithmic (log- log) regressions were performed. He chose the log-log curves because its variance was more uniform. The statistical comparison of .... E(U1| U2 = u2) is the regression function of U1 on U2, and Var (U1|U2 = u2) is the conditional covariance matrix.
Organochlorine pesticide compounds in organisms from the Bay of Bengal
Digital Repository Service at National Institute of Oceanography (India)
Shailaja, M.S.; Singbal, S.Y.S.
tissues and 4.00 to 1587.76 ng g @u-1@@ wet weight in zoolankton were found. Aldrin levels were of the order of 0.32-4.23 ng g @u-1@@ in the fish ittues and 'not detected' to 0.78 ng g @u-1@@ in zooplankton. The concentration levels are discussed...
Two-field Born–Infeld with diverse dualities
Directory of Open Access Journals (Sweden)
S. Ferrara
2016-11-01
Full Text Available We elaborate on how to build, in a systematic fashion, two-field Abelian extensions of the Born–Infeld Lagrangian. These models realize the non-trivial duality groups that are allowed in this case, namely U(2, SU(2 and U(1×U(1. For each class, we also construct an explicit example. They all involve an overall square root and reduce to the Born–Infeld model if the two fields are identified, but differ in quartic and higher interactions. The U(1×U(1 and SU(2 examples recover some recent results obtained with different techniques, and we show that the U(1×U(1 model admits an N=1 supersymmetric completion. The U(2 example includes some unusual terms that are not analytic at the origin of field space.
International Nuclear Information System (INIS)
Sharma, Aarti; Lambrechts, Anja; Le thi Hao; Le, Thanh T.; Sewry, Caroline A.; Ampe, Christophe; Burghes, Arthur H.M.; Morris, Glenn E.
2005-01-01
Spinal muscular atrophy (SMA) is caused by reduced levels of SMN (survival of motor neurons protein) and consequent loss of motor neurons. SMN is involved in snRNP transport and nuclear RNA splicing, but axonal transport of SMN has also been shown to occur in motor neurons. SMN also binds to the small actin-binding protein, profilin. We now show that SMN and profilin II co-localise in the cytoplasm of differentiating rat PC12 cells and in neurite-like extensions, especially at their growth cones. Many components of known SMN complexes were also found in these extensions, including gemin2 (SIP-1), gemin6, gemin7 and unrip (unr-interacting protein). Coilin p80 and Sm core protein immunoreactivity, however, were seen only in the nucleus. SMN is known to associate with β-actin mRNA and specific hnRNPs in axons and in neurite extensions of cultured nerve cells, and SMN also stimulates neurite outgrowth in cultures. Our results are therefore consistent with SMN complexes, rather than SMN alone, being involved in the transport of actin mRNPs along the axon as in the transport of snRNPs into the nucleus by similar SMN complexes. Antisense knockdown of profilin I and II isoforms inhibited neurite outgrowth of PC12 cells and caused accumulation of SMN and its associated proteins in cytoplasmic aggregates. BIAcore studies demonstrated a high affinity interaction of SMN with profilin IIa, the isoform present in developing neurons. Pathogenic missense mutations in SMN, or deletion of exons 5 and 7, prevented this interaction. The interaction is functional in that SMN can modulate actin polymerisation in vitro by reducing the inhibitory effect of profilin IIa. This suggests that reduced SMN in SMA might cause axonal pathfinding defects by disturbing the normal regulation of microfilament growth by profilins
Huang, Shuai; Balgi, Aruna; Pan, Yaping; Li, Meng; Zhang, Xiaoran; Du, Lilin; Zhou, Ming; Roberge, Michel; Li, Xin
2016-12-05
Nucleotide-binding leucine-rich repeat (NLR) proteins serve as immune receptors in both plants and animals. To identify components required for NLR-mediated immunity, we designed and carried out a chemical genetics screen to search for small molecules that can alter immune responses in Arabidopsis thaliana. From 13 600 compounds, we identified Ro 8-4304 that was able to specifically suppress the severe autoimmune phenotypes of chs3-2D (chilling sensitive 3, 2D), including the arrested growth morphology and heightened PR (Pathogenesis Related) gene expression. Further, six Ro 8-4304 insensitive mutants were uncovered from the Ro 8-4304-insensitive mutant (rim) screen using a mutagenized chs3-2D population. Positional cloning revealed that rim1 encodes an allele of AtICln (I, currents; Cl, chloride; n, nucleotide). Genetic and biochemical analysis demonstrated that AtICln is in the same protein complex with the methylosome components small nuclear ribonucleoprotein D3b (SmD3b) and protein arginine methyltransferase 5 (PRMT5), which are required for the biogenesis of small nuclear ribonucleoproteins (snRNPs) involved in mRNA splicing. Double mutant analysis revealed that SmD3b is also involved in the sensitivity to Ro 8-4304, and the prmt5-1 chs3-2D double mutant is lethal. Loss of AtICln, SmD3b, or PRMT5 function results in enhanced disease resistance against the virulent oomycete pathogen Hyaloperonospora arabidopsidis Noco2, suggesting that mRNA splicing plays a previously unknown negative role in plant immunity. The successful implementation of a high-throughput chemical genetic screen and the identification of a small-molecule compound affecting plant immunity indicate that chemical genetics is a powerful tool to study whole-organism plant defense pathways. Copyright Â© 2016 The Author. Published by Elsevier Inc. All rights reserved.
Soulez, M; Saurin, A J; Freemont, P S; Knight, J C
1999-04-29
Chromosome translocation t(X;18)(p11.2;q11.2) is unique to synovial sarcomas and results in an 'in frame' fusion of the SYT gene with the SSX1 or closely-related SSX2 gene. Wild-type SYT and SSX proteins, and the SYT-SSX chimaeric proteins, can modulate transcription in gene reporter assays. To help elucidate the role of these proteins in cell function and neoplasia we have performed immunolabelling experiments to determine their subcellular localization in three cell types. Transient expression of epitope-tagged proteins produced distinctive nuclear staining patterns. The punctate staining of SYT and SYT-SSX proteins showed some similarities. We immunolabelled a series of endogenous nuclear antigens and excluded the SYT and SYT-SSX focal staining from association with these domains (e.g. sites of active transcription, snRNPs). In further experiments we immunolabelled the Polycomb group (PcG) proteins RING1 or BMI-1 and showed that SSX and SYT-SSX proteins, but not SYT, co-localized with these markers. Consistent with this we show that SSX and SYT-SSX associate with chromatin, and also associate with condensed chromatin at metaphase. Noteably, SSX produced a dense signal over the surface of metaphase chromosomes whereas SYT-SSX produced discrete focal staining. Our data indicate that SSX and SYT-SSX proteins are recruited to nuclear domains occupied by PcG complexes, and this provides us with a new insight into the possible function of wild-type SSX and the mechanism by which the aberrant SYT-SSX protein might disrupt fundamental mechanisms controlling cell division and cell fate.
Discovery of a Splicing Regulator Required for Cell Cycle Progression
Energy Technology Data Exchange (ETDEWEB)
Suvorova, Elena S.; Croken, Matthew; Kratzer, Stella; Ting, Li-Min; Conde de Felipe, Magnolia; Balu, Bharath; Markillie, Lye Meng; Weiss, Louis M.; Kim, Kami; White, Michael W.
2013-02-01
In the G1 phase of the cell division cycle, eukaryotic cells prepare many of the resources necessary for a new round of growth including renewal of the transcriptional and protein synthetic capacities and building the machinery for chromosome replication. The function of G1 has an early evolutionary origin and is preserved in single and multicellular organisms, although the regulatory mechanisms conducting G1 specific functions are only understood in a few model eukaryotes. Here we describe a new G1 mutant from an ancient family of apicomplexan protozoans. Toxoplasma gondii temperature-sensitive mutant 12-109C6 conditionally arrests in the G1 phase due to a single point mutation in a novel protein containing a single RNA-recognition-motif (TgRRM1). The resulting tyrosine to asparagine amino acid change in TgRRM1 causes severe temperature instability that generates an effective null phenotype for this protein when the mutant is shifted to the restrictive temperature. Orthologs of TgRRM1 are widely conserved in diverse eukaryote lineages, and the human counterpart (RBM42) can functionally replace the missing Toxoplasma factor. Transcriptome studies demonstrate that gene expression is downregulated in the mutant at the restrictive temperature due to a severe defect in splicing that affects both cell cycle and constitutively expressed mRNAs. The interaction of TgRRM1 with factors of the tri-SNP complex (U4/U6 & U5 snRNPs) indicate this factor may be required to assemble an active spliceosome. Thus, the TgRRM1 family of proteins is an unrecognized and evolutionarily conserved class of splicing regulators. This study demonstrates investigations into diverse unicellular eukaryotes, like the Apicomplexa, have the potential to yield new insights into important mechanisms conserved across modern eukaryotic kingdoms.
Higgs mechanism and cosmological constant in N = 1 supergravity with inflaton in a vector multiplet
Energy Technology Data Exchange (ETDEWEB)
Aldabergenov, Yermek [Tokyo Metropolitan University, Department of Physics, Tokyo (Japan); Ketov, Sergei V. [Tokyo Metropolitan University, Department of Physics, Tokyo (Japan); The University of Tokyo, Kavli Institute for the Physics and Mathematics of the Universe (IPMU), Chiba (Japan); Tomsk Polytechnic University, Institute of Physics and Technology, Tomsk (Russian Federation)
2017-04-15
The N = 1 supergravity models of cosmological inflation with an inflaton belonging to a massive vector multiplet and spontaneous SUSY breaking after inflation are reformulated as the supersymmetric U(1) gauge theories of a massless vector superfield interacting with the Higgs and Polonyi chiral superfields, all coupled to supergravity. The U(1) gauge sector is identified with the U(1) gauge fields of the super-GUT coupled to supergravity, whose gauge group has a U(1) factor. A positive cosmological constant (dark energy) is included. The scalar potential is calculated, and its de Sitter vacuum solution is found to be stable. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Tamvakis, K.
1988-01-28
We construct an N=1 supersymmetric SO(10) GUT broken down to SU(3)c x SU(2)/sub L/ x U(1)/sub ..gamma../ with an intermediate flipped SU(5) x U(1)/sub chi/ gauge symmetry. A solution to the triplet-doublet mass-splitting problem is proposed in terms of a non-minimal missing-partner mechanism.
Digital Repository Service at National Institute of Oceanography (India)
Dhargalkar, V.K.
discrete depths. Chl @ia@@ concentration at all the 3 depths varied from 0.026 to 0.253 mu g l@u-1@@ showing minimum values during August-September. POC values varied from 280 to 1058 mu g l@u-1@@ while its constituent fractions such as particulate...
Abelian gauge theories on homogeneous spaces
International Nuclear Information System (INIS)
Vassilevich, D.V.
1992-07-01
An algebraic technique of separation of gauge modes in Abelian gauge theories on homogeneous spaces is proposed. An effective potential for the Maxwell-Chern-Simons theory on S 3 is calculated. A generalization of the Chern-Simons action is suggested and analysed with the example of SU(3)/U(1) x U(1). (author). 11 refs
Physics with large extra dimensions
Indian Academy of Sciences (India)
can then be accounted by the existence of large internal dimensions, in the sub- ... strongly coupled heterotic theory with one large dimension is described by a weakly ..... one additional U(1) factor corresponding to an extra 'U(1)' D-brane is ...
On gauged Baryon and Lepton numbers
International Nuclear Information System (INIS)
Rajpoot, S.
1990-01-01
The observation that Baryon number and Lepton number are conserved in nature provides strong motivation for associating gauge symmetries to these conserved numbers. This endeavor requires that the gauge group of electroweak interactions be extended from SU(2) L X U(1) Y to SU(2) L X U(1) R X U(1) Lepton where U(1) R couples only to the right-handed quarks and leptons. If it furthur postulated that right-handed currents exist on par with the left-handed ones, then the full electroweak symmetry is SU(2) L X SU(2) R X U(1) Baryon X U(1) Lepton . The SU(2) L X SU(2) R X U(1) Baryon X U(1) Lepton model is described in some detail. The triangle anomalies of the three families of quarks and leptons in the model are cancelled invoking leptoquark matter which is new fermionic matter that carries baryon as well as lepton numbers. In addition to the standard neutral boson (Z degree), the theory predicts two neutral gauge bosons with mass lower bounds of 120 GeV and 210 GeV which makes these particles prospective candidates for production at LEP, the TEVATRON and the SSC
Pramana – Journal of Physics | Indian Academy of Sciences
Indian Academy of Sciences (India)
2017-10-09
Oct 9, 2017 ... Fermions in the dark sector also carry a global U ( 1 ) H charge while the gauge bosons and dark scalar do not have any global U ( 1 ) H charge. The lightest fermion in dark sector can serve as a potential dark matter candidate. We investigate whether the proposed dark matter candidate can explain indirect ...
Yeast Interacting Proteins Database: YGR013W, YKL012W [Yeast Interacting Proteins Database
Lifescience Database Archive (English)
Full Text Available tion U1 snRNP protein involved in splicing, interacts with the branchpoint-binding protein during the formation of the second commitm... PRP40 U1 snRNP protein involved in splicing, interacts with the branchpoint-binding protein during the form...ation of the second commitment complex Rows with this prey as prey (1) Rows with
Journal of Genetics | Indian Academy of Sciences
Indian Academy of Sciences (India)
Home; Journals; Journal of Genetics. IOANNA ALEXANDROU. Articles written in Journal of Genetics. Volume 95 Issue 3 September 2016 pp 621-624 Regular Articles. Deletion of SNURF / SNRPN U1B and U1B* upstream exons in a child with developmental delay and excessive weight · COSTAS KOUFARIS ANGELOS ...
Gauge theories on a small lattice
International Nuclear Information System (INIS)
Robson, D.; Webber, D.M.
1980-01-01
We present exact solutions to U(1), SU(2), and SU(3) lattice gauge theories on a Kogut-Susskind lattice consisting of a single plaquette. We demonstrate precise equivalence between the U(1) theory and the harmonic oscillator on an infinite one-dimensional lattice, and between the SU(N) theory and an N-fermion Schroedinger equation. (orig.)
Gauge and gravitational anomalies in D=4 N=1 orientifolds.
S Scrucca, C.; Serone, M.
1999-01-01
We analyze in detail the cancellation of U(1)-gauge and U(1)-gravitational anomalies in certain D=4 N=1 Type IIB orientifolds, from a string theory point of view. We verify the proposal that these anomalies are cancelled by a Green-Schwarz mechanism involving only twisted RR fields.By factorizing
A unified theory in higher dimensions
Energy Technology Data Exchange (ETDEWEB)
Kapetanakis, D. (National Research Centre for the Physical Sciences Democritos, Athens (Greece)); Zoupanos, G. (European Organization for Nuclear Research, Geneva (Switzerland))
1990-10-11
We present a grand unified model defined in ten dimensions and based on the group SO(13). The model is dimensionally reduced over the non-simply-connected space (Su(3)/U(1)xU(1))/Z{sub 2} giving in four dimensions the standard model. (orig.).
A unified theory in higher dimensions
International Nuclear Information System (INIS)
Kapetanakis, D.; Zoupanos, G.
1990-01-01
We present a grand unified model defined in ten dimensions and based on the group SO(13). The model is dimensionally reduced over the non-simply-connected space [Su(3)/U(1)xU(1)]/Z 2 giving in four dimensions the standard model. (orig.)
Nitrogen uptake by phytoplankton and zooxanthellae in a coral atoll
Digital Repository Service at National Institute of Oceanography (India)
Wafar, M.V.M.; Devassy, V.P.; Slawyk, G.; Goes, J.I.; Jayakumar, D.A.; Rajendran, A.
by corals, and the rates varied from 223 to 775 ng-at (mg coral tissue) @u-1@@h@u-1@@ in 4 species. Urea excretion forms about 5% of total N excreted. N balance (NH@d4@@, urea, NO@d3@@) calculated from 4 species of corals shows that zooxanthellae can derive...
DEFF Research Database (Denmark)
Kromann-Hansen, Tobias; Lund, Ida K; Liu, Zhuo
2013-01-01
for elucidating fundamental allosteric mechanisms. The monoclonal antibody mU1 has previously been shown to be able to inhibit the function of murine urokinase-type plasminogen activator in vivo. We have now mapped the epitope of mU1 to the catalytic domain's 37- and 70-loops, situated about 20 Å from the S1...
Discrete gauge symmetries in discrete MSSM-like orientifolds
International Nuclear Information System (INIS)
Ibáñez, L.E.; Schellekens, A.N.; Uranga, A.M.
2012-01-01
Motivated by the necessity of discrete Z N symmetries in the MSSM to insure baryon stability, we study the origin of discrete gauge symmetries from open string sector U(1)'s in orientifolds based on rational conformal field theory. By means of an explicit construction, we find an integral basis for the couplings of axions and U(1) factors for all simple current MIPFs and orientifolds of all 168 Gepner models, a total of 32 990 distinct cases. We discuss how the presence of discrete symmetries surviving as a subgroup of broken U(1)'s can be derived using this basis. We apply this procedure to models with MSSM chiral spectrum, concretely to all known U(3)×U(2)×U(1)×U(1) and U(3)×Sp(2)×U(1)×U(1) configurations with chiral bi-fundamentals, but no chiral tensors, as well as some SU(5) GUT models. We find examples of models with Z 2 (R-parity) and Z 3 symmetries that forbid certain B and/or L violating MSSM couplings. Their presence is however relatively rare, at the level of a few percent of all cases.
Signatures of exotic fermions and other new ''low-energy'' phenomena in superstring E6
International Nuclear Information System (INIS)
Rosner, J.L.
1986-03-01
Superstring theories have drawn renewed attention to the exceptional group E 6 as a grand unified theory. We discuss the extra U(1) symmetries (beyond that in the standard SU(3) x SU(2) x U(1) model) that arise when E 6 is broken in such theories. These extra U(1)'s must lead to at least one extra neutral gauge boson, called Z', for which we give mass limits and branching ratios. Neutral current effects of this Z' and its direct production are discussed briefly. Finally, some signatures are noted of exotic fermions to which Z' can decay
Natural embedding of Peccei-Quinn symmetry in flavor grand unification
International Nuclear Information System (INIS)
Kim, J.E.
1981-08-01
Peccei and Quinn's global U(1)sub(A) symmetry can be embedded in grand unified schemes without an artificial requirement of imposing U(1)sub(A) symmetry, which results from the representation content of fermions and Higgs fields. Then, in some cases there results an ordinary axion with a mass approximately 100 keV. The axion mass is proportional to v -1 sub(A), where v -1 sub(A) is the scale of the actual U(1)sub(A) symmetry breakdown. (author)
A note on analytical solutions of nonlinear fractional 2D heat ...
Indian Academy of Sciences (India)
2016-09-09
Sep 9, 2016 ... In the same way, um(x,t) for m = 4,5,6,... can be obtained using symbolic mathematics package/ symbolic computation software such as Mathematica. For example, to compute u3(x,t), the following for- mula is used: u3(x,y,t) = χ. ∗. 3 u2 +hI α t. [. Pα t u2 −u0(u2)xx −u1(u1)xx. −u2(u0)xx − 2(u0)x(u2)x − (u1). 2.
Fermion zero modes in the vortex background of a Chern-Simons-Higgs theory with a hidden sector
Energy Technology Data Exchange (ETDEWEB)
Lozano, Gustavo [Departamento de Física, FCEYN Universidad de Buenos Aires & IFIBA CONICET,Pabellón 1 Ciudad Universitaria, 1428 Buenos Aires (Argentina); Mohammadi, Azadeh [Departamento de Física, Universidade Federal da Paraíba,58.059-970, Caixa Postal 5.008, João Pessoa, PB (Brazil); Schaposnik, Fidel A. [Departamento de Física, Universidad Nacional de La Plata/IFLP/CICBA,CC 67, 1900 La Plata (Argentina)
2015-11-06
In this paper we study a 2+1 dimensional system in which fermions are coupled to the self-dual topological vortex in U(1)×U(1) Chern-Simons theory, where both U(1) gauge symmetries are spontaneously broken. We consider two Abelian Higgs scalars with visible and hidden sectors coupled to a fermionic field through three interaction Lagrangians, where one of them violates the fermion number. Using a fine tuning procedure, we could obtain the number of the fermionic zero modes which is equal to the absolute value of the sum of the vortex numbers in the visible and hidden sectors.
The standard model from a gauge theory in ten dimensions via CSDR
International Nuclear Information System (INIS)
Farakos, K.; Kapetanakis, D.; Koutsoumbas, G.; Zoupanos, G.
1988-01-01
We present a gauge theory in ten dimensions based on the gauge group E 8 which is dimensionally reduced, according to the coset space dimensional reduction (CSDR) scheme, to the standard model SU 3c xSU 2L xU 1 , which breaks further to SU 3c xU 1em . We use the coset space Sp 4 /(SU 2 xU 1 )xZ 2 . The model gives similar predictions for sin 2 θ w and proton decay as the minimal SU 5 GUT. Natural choices of parameters suggest that the Higgs masses are as predicted by the Coleman-Weinberg radiative mechanism. (orig.)
Studies on the ecology of insects sterilized artificially (gamma radiation), 9
International Nuclear Information System (INIS)
Kiyoku, Masao; Tsukuda, Ritsuko
1975-01-01
The pupae of oriental fruitfly were irradiated with the 137Cs-γ ray of 7.5 krad two days before emerging. Adult males emerged were crossed with untreated females(T #male# x Uo #female#). The progenies F1 #male# and F1 #female# from T #male# x Uo #female# were crossed with each other (F1 #male# x f1 #female#) or with untreated progenies U1 #female# and U1 male (F1 #male# x U1 #female#, U1 #male# x F1 #female#), respectively. Starting from these three combinations, various mating experiments were conducted from F2 to F5-generations. The rate of hatching of the eggs obtained from F1 #male# x F1 #female# was the lowest, about a half of that from the control U1 #male# x U1 #female#. The rate of hatching of those from F1 #male# x U1 #female# or U1 #male# x F1 #female# was lower than that from the control, but slightly higher than that from F1 #male# x F1 #female#. The combination, Fn #male# x Fn #female#, in the offsprings descended from F1 #male# x F1 #female# maintained the low percentage hatching of eggs during the successive four generations. However, the rate of those from Fn #male# x Un #female# and Un #male# x Fn #female# in the offsprings descended from F1 #male# x U1 #female# or U1 #male# x F1 #female# tended to rise by F3 or F4 generation. Percentages of the pupation and emergence of F1 #male# x F1 #female#, F1 #male# x U1 #female# and U1 #male# x F1 #female# were somewhat lower than those of the control. Although the percentages of those of three combinations, F2 #male# x F2 #female#, f2' #male# x F2' #female# and F2'' #male# x F2'' #female#, were also lower than those of the control, such decrease in the percentages of pupation and emergence of the other combinations in the second generation and all combinations after the third generation was inconspicuous, except those of Fn #male# x Fn #female#. The difference in the days of survival between Fn #male# and Un #female# adults was not significant, or the days of survival of Fn #male# adults were somewhat
R parity in standard-like superstring models
International Nuclear Information System (INIS)
Halyo, Edi.
1994-01-01
We investigate the R symmetries of standard-like superstring models. At the level of the cubic superpotential there are three global U(1) R symmetries. These are broken explicitly by N > 3 terms in the superpotential and spontaneously by scalar Vacuum Expectation values necessary to preserve supersymmetry at Mp. A Z 2 discrete symmetry remains but is equivalent to fermion number modulo 2. These models possess an effective R parity which arises from the interplay between the gauged U(1) B-L and U(1) r j+3 . (author). 14 refs
Perspectives on managing nuclear safety at Cernavoda NPP past, present and future
International Nuclear Information System (INIS)
Serban, M.
1997-01-01
The presentation considers the following issues: background of Romanian nuclear programme; 1990 management issues involved in Cernavoda project, nuclear safety perspectives; Cernavoda U1 operating organization today (safety related issues); good practices at Cernavoda NPP
Cultivation of Agaricus bisporus on some compost formulas and ...
African Journals Online (AJOL)
AJB SERVER
2007-01-18
Jan 18, 2007 ... Agaricus bisporus, is produced from wheat straw, straw- bedded horse .... mycelium (Type Horst U1) per kg then filled into plastic bags as 7 kg wet weight basis. ... a selective substrate environment for mushroom growing.
Cultivation of Agaricus bisporus on some compost formulas and ...
African Journals Online (AJOL)
SERVER
2007-10-04
Oct 4, 2007 ... Three compost formulas; wheat straw based and using different activator materials such as .... mycelium (Type Horst U1) per kg then filled into plastic bags as 7 ... a selective substrate environment for mushroom growing.
Perspectives on managing nuclear safety at Cernavoda NPP past, present and future
Energy Technology Data Exchange (ETDEWEB)
Serban, M [Technical Safety Directorate, Unit 1., Cernavoda Nuclear Power Plant (Romania)
1997-12-01
The presentation considers the following issues: background of Romanian nuclear programme; 1990 management issues involved in Cernavoda project, nuclear safety perspectives; Cernavoda U1 operating organization today (safety related issues); good practices at Cernavoda NPP.
Phenotype abnormality: 311 [Arabidopsis Phenome Database[Archive
Lifescience Database Archive (English)
Full Text Available 311 http://metadb.riken.jp/db/SciNetS_ria224i/cria224u1ria224u816i increased efficiency during process... named seed dormancy process ... increased efficiency ... seed dormancy process ...
Phenotype abnormality: 135 [Arabidopsis Phenome Database[Archive
Lifescience Database Archive (English)
Full Text Available 135 http://metadb.riken.jp/db/SciNetS_ria224i/cria224u1ria224u641i decreased efficiency during process... named seed dormancy process ... decreased efficiency ... seed dormancy process ...
Current problems in the weak interactions
International Nuclear Information System (INIS)
Pais, A.
1977-01-01
Some reasons are discussed showing why the recent SU(2) x U(1) gauge theory of weak and electromagnetic interactions is not a complete theory of these interactions, Lepton theory, charm, and the CP problem are considered. 60 references
Threshold corrections and gauge symmetry in twisted superstring models
International Nuclear Information System (INIS)
Pierce, D.M.
1994-01-01
Threshold corrections to the running of gauge couplings are calculated for superstring models with free complex world sheet fermions. For two N=1 SU(2)xU(1) 5 models, the threshold corrections lead to a small increase in the unification scale. Examples are given to illustrate how a given particle spectrum can be described by models with different boundary conditions on the internal fermions. We also discuss how complex twisted fermions can enhance the symmetry group of an N=4, SU(3)xU(1)xU(1) model to the gauge group SU(3)xSU(2)xU(1). It is then shown how a mixing angle analogous to the Weinberg angle depends on the boundary conditions of the internal fermions
Unconstrained off-shell N=3 supersymmetric Yang-Mills theory
International Nuclear Information System (INIS)
Galperin, A.; Ivanov, E.; Kalitzin, S.; Ogievetsky, V.; Sokatchev, E.
1984-01-01
The harmonic superspace is used to build up an unconstrained off-shell formulation of N=3 supersymmetric Yang-Mills theory. The theory is defined in an analytic N=3 superspace having M 4 x(SU(3)/U(1)xU(1) as an even part. The basic objects are the analytic potentials which serve as gauge connections entering harmonic derivatives. The action is an integral over analytic superspace. The Lagrange density is surprisingly simple and it is gauge invariant up to total harmonic derivative. The equations of motion are integrability conditions on the internal space SU(3)/U(1)xU(1). The jumping over the ''N=3 barrier'' became possible due to the infinite number of auxiliary fields
Denitrification processes in the Arabian Sea
Digital Repository Service at National Institute of Oceanography (India)
Naqvi, S.W.A.
rate in the vicinity of 30 Tg Ny@u-1@@, but the extent of benthic contribution remains unknown. A decoupling of denitrification from primary production, unique to the Arabian Sea, is revealed by nitrite, Electron Transport System (ETS) activity...
Path integral for coherent states of the dynamical U2 group and U2/1 supergroup
International Nuclear Information System (INIS)
Kochetov, E.A.
1992-01-01
A part-integral formulation in the representation of coherent states for the unitary U 2 group and U 2/1 supergroup is introduced. U 2 and U 2/1 path integrals are shown to be defined on the coset spaces U 2 /U 1 xU 1 and U 2/1 /U 1/1 xU 1 , respectively. These coset appears as curved classical phase spaces. Partition functions are expressed as path integrals over these spaces. In the case when U 2 and U 2/1 are the dynamical groups, the corresponding path integrals are evaluated with the help of linear fractional transformations that appear as the group (supergroup) action in the coset space (superspace). Possible applications for quantum models are discussed. 9 refs
Phenotype abnormality: 213 [Arabidopsis Phenome Database[Archive
Lifescience Database Archive (English)
Full Text Available 213 http://metadb.riken.jp/db/SciNetS_ria224i/cria224u1ria224u719i decreased sensitivity toward under influ...ence of brassinosteroid ... decreased sensitivity toward ... brassinosteroid ...
Phenotype abnormality: 236 [Arabidopsis Phenome Database[Archive
Lifescience Database Archive (English)
Full Text Available 236 http://metadb.riken.jp/db/SciNetS_ria224i/cria224u1ria224u742i decreased susceptibility... in response to organism Agrobacterium ... Agrobacterium ... decreased susceptibility toward ...
Classification and properties of quantum spin liquids on the hyperhoneycomb lattice
Huang, Biao; Choi, Wonjune; Kim, Yong Baek; Lu, Yuan-Ming
2018-05-01
The family of "Kitaev materials" provides an ideal platform to study quantum spin liquids and their neighboring magnetic orders. Motivated by the possibility of a quantum spin liquid ground state in pressurized hyperhoneycomb iridate β -Li2IrO3 , we systematically classify and study symmetric quantum spin liquids on the hyperhoneycomb lattice, using the Abrikosov-fermion representation. Among the 176 symmetric U (1 ) spin liquids (and 160 Z2 spin liquids), we identify eight "root" U (1 ) spin liquids in proximity to the ground state of the solvable Kitave model on the hyperhonecyomb lattice. These eight states are promising candidates for possible U (1 ) spin liquid ground states in pressurized β -Li2IrO3 . We further discuss physical properties of these eight U (1 ) spin liquid candidates, and show that they all support nodal-line-shaped spinon Fermi surfaces.
On the stringy Hartle-Hawking state
Ben-Israel, Roy; Giveon, Amit; Itzhaki, Nissan; Liram, Lior
2016-03-01
We argue that non-perturbative α' stringy effects render the Hartle-Hawking state associated with the SL(2)/U(1) eternal black hole singular at the horizon. We discuss implications of this observation on firewalls in string theory.
Noncommuting fields and non-Abelian fluids
International Nuclear Information System (INIS)
Jackiw, R.
2004-01-01
The original ideas about noncommuting coordinates are recalled. The connection between U(1) gauge fields defined on noncommuting coordinates and fluid mechanics is explained. Non-Abelian fluid mechanics is described
Z flux-line lattices and self-dual equations in the standard model
International Nuclear Information System (INIS)
Bimonte, G.; Lozano, G.
1994-04-01
We derive gauge covariant self-dual equations for the SU(2) x U(1) y theory of electroweak interactions and show that they admit solutions describing a periodic lattice of Z-strings. (author). 14 refs
Probabilistic programmable quantum processors with multiple copies of program states
International Nuclear Information System (INIS)
Brazier, Adam; Buzek, Vladimir; Knight, Peter L.
2005-01-01
We examine the execution of general U(1) transformations on programmable quantum processors. We show that, with only the minimal assumption of availability of copies of the 1-qubit program state, the apparent advantage of existing schemes proposed by G. Vidal et al. [Phys. Rev. Lett. 88, 047905 (2002)] and M. Hillery et al. [Phys. Rev. A 65, 022301 (2003)] to execute a general U(1) transformation with greater probability using complex program states appears not to hold
Supersymmetry breaking through confining and dual theory gauge dynamics
International Nuclear Information System (INIS)
Csaki, C.; Massachusetts Inst. of Tech., Cambridge, MA; Randall, L.; Massachusetts Inst. of Tech., Cambridge, MA; Skiba, W.; Massachusetts Inst. of Tech., Cambridge, MA; Leigh, R.G.
1997-01-01
We show that theories in the confining, free magnetic, and conformal phases can break supersymmetry through dynamical effects. To illustrate this, we present theories based on the gauge groups SU(n) x SU(4) x U(1) and SU(n) x SU(5) x U(1) with the field content obtained by decomposing an SU(m) theory with an antisymmetric tensor and m - 4 antifundamentals. (orig.)
Lifescience Database Archive (English)
Full Text Available e dehydrogenase (Fragment) OS=Arab... 50 7e-05 tr|Q84JM5|Q84JM5_IPONI Angustifolia OS=Ipomoea nil GN=IAN PE=... 0.015 tr|B6U1W6|B6U1W6_MAIZE Angustifolia OS=Zea mays PE=2 SV=1 42 0.015 tr|A3C6