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O problema da violação CP forte e extensões ´SU(3) IND.C´ ´Ä´ ´SU(3) IND.L´´Ä´´U(1) IND.X´ do modelo padrão.; The strong CP problem and the perturbative limit in SU(3)xSU(3)xU(1) standard model extensions.

Dias, Alex Gomes
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 16/06/2005 PT
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35.99%
Nesta tese apresentamos um estudo de como as simetrias grandes podem tornar as soluções de problemas como o da violação CP forte, mais naturais. Em particular, trataremos de estensões SU(3) IND.C""SU(3) IND.L"U (1) IND.X do modelo Padrão. Veremos como uma simetria discreta grande torna automática, em nível clássico, a simetria de Peccei-Quinn. O áxion do tipo invisível tem a sua massa protegida contra os efeitos semi-clássicos de gravitação quântica através da simetria Z IND.N. O limite perturbativo desses modelos também é investigado. A classe de modelos em que a simetria discreta é quase automática tem a sua validade perturbativa apenas em uma escala de energia relativamente baixa, na ordem dos TeV. É, então, proposta a extensão com um conteúdo mínimo de representação adicional onde o limite perturbativo pode ser ampliado para escalas de mais de uma dezena de TeV; deixando, portanto, esses modelos mais atrativos do ponto de vista fenomenológiconas energias que estarão sendo alcançadas em um futuro próximo nos aceleradores de partículas.; In this thesis we perform a study about how large discrete symmetries can make problems solutions like the strong CP violation, more natural. In particular, we shall treat of a SU(3)cSU(3)LU(1)x Standard Model extension. We shall see how a large discrete symmetry makes...

Interações não padrão de neutrinos no modelo 331 com setor de Higgs mínimo; Non-standard interactions of neutrinos in the 331 model with minimal Higgs sector

Miguel Medina Jaime
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 10/04/19 PT
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36.35%
Neste trabalho apresentamos um estudo de alguns problemas que ainda não forem esclarecidos na física de neutrinos do modelo padrão (MP) e encaminhamos eles na direção de física nova. Para esse fim, estuda-se uma classe de extensões de Gauge quirais do MP com simetria SU(3)C x SU(3)L x U(1)X (modelos 331), onde estudamos a interação eletrofraca dos neutrinos com a matéria via correntes carregadas e neutras (CC e CN) através dos bósons Gauge do modelo para processos de espalhamento elástico coerente. Finalmente, encontramos vínculos entre as contribuições não padrão no modelo 331 com as interações não padrão (INP) em experimentos de seção de choque, onde encontramos que o modelo 331 apresenta INP diagonais universais da ordem e a M2 W,Z / M2 X <~ O(10-3). Mostramos que o valor esperado no vácuo (VEV) para o tão procurado bóson de Higgs neste modelo tem que ser ?2 <~174.105GeV e os VEV V > 1.3TeV e 142 GeV < ?1 < 201GeV. Os novos bósons do modelo deverão ter massas maiores a 610 GeV; We present a study of some problems that are not yet clarified in Standard Model (SM) neutrino physics and guide them in the direction of new physics. To this aim, we study a class of extensions of the SM Gauge chiral symmetry SU(3)CSU(3)LU(1)X (331 model)...

Fludarabine induces apoptosis in chronic lymphocytic leukemia - the role of P53, Bcl-2, Bax, Mcl-1, and Bag-1 proteins

Faria,J.R.; Yamamoto,M.; Faria,R.M.D.; Kerbauy,J.; Oliveira,J.S.R.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2006 EN
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36.13%
The expression of P53, Bcl-2, Bax, Bag-1, and Mcl-1 proteins in CD5/CD20-positive B-chronic lymphocytic leukemia (B-CLL) cells from 30 typical CLL patients was evaluated before and after 48 h of incubation with 10-6 M fludarabine using multiparametric flow cytometric analysis. Protein expression was correlated with annexin V expression, Rai modified clinical staging, lymphocyte doubling time, and previous treatment. Our main goal was to determine the predictive value of these proteins in CLL cells in terms of disease evolution. Bcl-2 expression decreased from a median fluorescence index (MFI) of 331.71 ± 42.2 to 245.81 ± 52.2 (P < 0.001) after fludarabine treatment, but there was no difference between viable cells (331.57 ± 44.6 MFI) and apoptotic cells (331.71 ± 42.2 MFI) before incubation (P = 0.859). Bax expression was higher in viable cells (156.24 ± 32.2 MFI) than in apoptotic cells (133.56 ± 35.7 MFI) before incubation, probably reflecting defective apoptosis in CLL (P = 0.001). Mcl-1 expression was increased in fludarabine-resistant cells and seemed to be a remarkable protein for the inhibition of the apoptotic process in CLL (from 233.59 ± 29.8 to 252.04 ± 35.5; P = 0.033). After fludarabine treatment, Bag-1 expression was increased in fludarabine-resistant cells (from 425.55 ± 39.3 to 447.49 ± 34.5 MFI...

miRNA expression profiles in chronic lymphocytic and acute lymphocytic leukemia

Zanette,D.L.; Rivadavia,F.; Molfetta,G.A.; Barbuzano,F.G.; Proto-Siqueira,R.; Falcão,R.P.; Zago,M.A.; Silva-Jr,W.A.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2007 EN
Relevância na Pesquisa
26.2%
MicroRNAs (miRNAs) are a class of small endogenous RNAs that play important regulatory roles by targeting mRNAs for cleavage or translational repression. miRNAs act in diverse biological processes including development, cell growth, apoptosis, and hematopoiesis, suggesting their association with cancer. We determined the miRNA expression profile of chronic and acute lymphocytic leukemias (CLL and ALL) using the TaqMan® MicroRNA Assays Human Panel (Applied Biosystems). Pooled leukemia samples were compared to pooled CD19+ samples from healthy individuals (calibrator) by the 2-DDCt method. Total RNA input was normalized based on the Ct values obtained for hsa-miR-30b. The five most highly expressed miRNAs were miR-128b, miR-204, miR-218, miR-331, and miR-181b-1 in ALL, and miR-331, miR-29a, miR-195, miR-34a, and miR-29c in CLL. To our knowledge, this is the first report associating miR-128b, miR-204 and miR-331 to hematological malignancies. The miR-17-92 cluster was also found to be up-regulated in ALL, as previously reported for some types of lymphomas. The differences observed in gene expression levels were validated for miR-331 and miR-128b in ALL and CD19+ samples. These miRNAs were up-regulated in ALL, in agreement with our initial results. A brief target analysis was performed for miR-331. One of its putative targets...

Identification of arginine 331 as an important active site residue in the class II fructose-1,6-bisphosphate aldolase of Escherichia coli.

Qamar, S.; Marsh, K.; Berry, A.
Fonte: Cold Spring Harbor Laboratory Press Publicador: Cold Spring Harbor Laboratory Press
Tipo: Artigo de Revista Científica
Publicado em /01/1996 EN
Relevância na Pesquisa
26.18%
Treatment of the Class II fructose-1,6-bisphosphate aldolase of Escherichia coli with the arginine-specific alpha-dicarbonyl reagents, butanedione or phenylglyoxal, results in inactivation of the enzyme. The enzyme is protected from inactivation by the substrate, fructose 1,6-bisphosphate, or by inorganic phosphate. Modification with [7-14C] phenylglyoxal in the absence of substrate demonstrates that enzyme activity is abolished by the incorporation of approximately 2 moles of reagent per mole of enzyme. Sequence alignment of the eight known Class II FBP-aldolases shows that only one arginine residue is conserved in all the known sequences. This residue, Arg-331, was mutated to either alanine or glutamic acid. The mutant enzymes were much less susceptible to inactivation by phenylglyoxal. Measurement of the steady-state kinetic parameters revealed that mutation of Arg-331 dramatically increased the K(m) for fructose 1,6-bisphosphate. Comparatively small differences in the inhibitor constant Ki for dihydroxyacetone phosphate or its analogue, 2-phosphoglycolate, were found between the wild-type and mutant enzymes. In contrast, the mutation caused large changes in the kinetic parameters when glyceraldehyde 3-phosphate was used as an inhibitor. Kinetic analysis of the oxidation of the carbanionic aldolase-substrate intermediate of the reaction by hexacyanoferrate (III) revealed that the K(m) for dihydroxyacetone phosphate was again unaffected...

Highly Cooperative Recruitment of Ets-1 and Release of Autoinhibition by Pax5

Fitzsimmons, Daniel; Lukin, Kara; Lutz, Ryan; Garvie, Colin W.; Wolberger, Cynthia; Hagman, James
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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Pax5 is a critical regulator of transcription and lineage commitment in B lymphocytes. In B cells, mb-1 (Ig-α) promoter transcription is activated by Pax5 through its recruitment of Ets family proteins to a composite site, the P5-EBS (Pax5-Ets binding site). Previously, X-ray crystallographic analysis revealed a network of contacts between the DNA binding domains of Pax5 and Ets-1 while bound to the P5-EBS. Here, we report that Pax5 assembles these ternary complexes via highly cooperative interactions that overcome the autoinhibition of Ets-1. Using recombinant proteins, we calculated KD(app) values for the binding of Pax5, Ets-1 and GABP proteins, separately or together, to the P5-EBS. By itself, Pax5 binds the P5-EBS with high affinity (KD ≅ 2 nM). Ets-1(331–440) bound the P5-EBS by itself with low affinity (KD = 136 nM). However, autoinhibited Ets-1(280–440) alone does not bind detectably to the suboptimal sequences of the P5-EBS. Recruitment of Ets-1(331–440) or (280–440) resulted in highly efficient ternary complex assembly with Pax5. Pax5 counteracts autoinhibition and increases binding of Ets-1 of the mb-1 promoter by >1000-fold. Mutation of Pax5 Gln22 to alanine (Q22A) enhances promoter binding by Pax5; however, Q22A greatly reduces recruitment of Ets-1(331–440) and (280–440) by Pax5 (8.9– or >300–fold...

Patient-reported Outcomes Following Treatment with the Human GLP-1 Analogue Liraglutide or Glimepiride in Monotherapy: Results from a Randomized Controlled Trial in Patients with Type 2 Diabetes

Bode, B W; Magwire, M; Hale, P M; Hammer, M; Blonde, L; Garber, A; Testa, Marcia Anne
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
35.81%
Aim: As weight gain and hypoglycaemia associated with glimepiride therapy can negatively impact weight perceptions, psychological well-being and overall quality of life in type 2 diabetes, we investigated whether liraglutide treatment could improve these factors. Methods: Seven hundred and thirty-two patients with type 2 diabetes completed a 77-item questionnaire during a randomized, 52-week, double-blind study with liraglutide 1.2 mg (n = 245) or 1.8 mg (n = 242) compared with glimepiride 8 mg (n = 245). Results: Mean (SE) decreases in glycated haemoglobin levels were greater with liraglutide 1.2 mg [−0.84 (0.08)%] and 1.8 mg [−1.14 (0.08)%] than glimepiride [−0.51 (0.08)%; p = 0.0014 and p < 0.0001, respectively]. Patients gained weight on glimepiride [mean (SE), 1.12 (0.27) kg] but lost weight on liraglutide [1.2 mg: −2.05 (0.28) kg; 1.8 mg: −2.45 (0.28) kg; both p < 0.0001]. Patient weight assessment was more favourable with liraglutide 1.8 mg [mean (SE) score: 40.0 (2.0)] than glimepiride [48.7 (2.0); p = 0.002], and liraglutide 1.8 mg patients were 52% less likely to feel overweight [odds ratio (OR) 0.48; 95% confidence interval (CI): 0.331–0.696]. Mean (SE) weight concerns were less with liraglutide [1.2 mg: 30.0 (1.2); 1.8 mg: 32.8 (1.2)] than glimepiride [38.8 (1.2); p < 0.0001 and p < 0.001...

Responsabilidade subsidiária da administração: reflexos da mudança do Enunciado nº 331 do TST

Pires, Maria Fernanda
Fonte: Editora Fórum Publicador: Editora Fórum
Tipo: Palestra
PT_BR
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26.1%
Duração: 25 minutos.; A presente palestra apresenta a controvérsia entre a Lei nº 8.666/93 e o Enunciado nº 331 e o respectivo entendimento do Supremo Tribunal Federal. A matéria foi divida em três partes: Terceirização no âmbito da Administração Pública, Controvérsia do Enunciado nº 331 do TST frente ao art. 71,§1º, da Lei n° 8.666, e a nova redação do Enunciado nº 331 e seus reflexos.

Kommunale Mandatsträger und Wahlbeamte im Spannungsfeld zwischen Kooperation und Korruption - Eine Untersuchung der Reichweite von §§ 331 ff. StGB -; Members of town and county councils as well as mayors and district administrators in the conflict between cooperation and corruption- An inquriy on the range of §§ 331 et sqq. StGB -

Kalbfell, Carl-Gustav
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
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Kommunale Mandatsträger und Wahlbeamte im Spannungsfeld zwischen Kooperation und Korruption - Eine Untersuchung der Reichweite von §§ 331 ff. StGB - Durch das „Gesetz zur Bekämpfung der Korruption“ vom 13. August 1997 wurden die Korruptionsdelikte durch die Einbeziehung von sog. Drittvorteilen in den Tatbestand der §§ 331 ff. StGB erheblich ausgedehnt. Seitdem sind Literatur und Rechtsprechung darum bemüht für viele Fallgestaltungen Kriterien zu entwickeln, um eine uferlose Ausdehnung der Korruptionsstrafbarkeit zu verhindern. Die vorliegende Arbeit untersucht unter welchen Voraussetzungen für Kommunalpolitiker wie Gemeinde- und Kreisräte (kommunale Mandatsträger) und (Ober-) Bürgermeister, Beigeordnete sowie Landräte (kommunale Wahlbeamte) eine Korruptionsstrafbarkeit im Raum steht, wenn sie mit finanziellen (Dritt-) Zuwendungen in Kontakt kommen. Solche (Dritt-)Zuwendungen sind insbesondere Gelder die Kommunalpolitiker für kommunale Aufgaben und Projekte einwerben, vermitteln oder annehmen. Unter dem Aspekt einer strafrechtlichen (Dritt-) Zuwendung sind ferner auch der Abschluss von Sponsoringvereinbarungen sowie städtebaulicher oder sonstiger öffentlich-rechtlicher Verträge zu prüfen. Des Weiteren wird untersucht...

Derecho sindical, texto guía / Francisca Ferrando García...[et al.].

Ferrando García, Francisca
Fonte: Murcia : DM, Publicador: Murcia : DM,
Tipo: Livro
SPA
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35.91%
LUIS VIVES. SALA. 331.1 FER der.; DERECHO. DEPARTAMENTO. E057 DS 544.; DERECHO. DEPARTAMENTO. E057 DS 545.

Z' production in 331 models

Dueñas,J. G.; Martínez,R.; Ochoa,F.
Fonte: Sociedade Brasileira de Física Publicador: Sociedade Brasileira de Física
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2008 EN
Relevância na Pesquisa
36.07%
We analyse the possibilities to detect a new Z' boson in di-electron events at LHC in the framework of the 331 model with right-handed neutrinos. For an integrated luminosity of 100fb-1 at LHC, and considering a central value Mz' = 1500 GeV, we obtain the invariant mass distribution in the process pp → Z' → e+e-, where a huge peak, corresponding to 800 signal events, is found above the SM background. The number of di-electron events vary from 10000 to 1 in the mass range of Mz' = 1000 - 5000 GeV.

Identification of 331 quantum Hall states with Mach-Zehnder interferometry

Wang, Chenjie; Feldman, D. E.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.1%
It has been shown recently that non-Abelian states and the spin-polarized and unpolarized versions of the Abelian 331 state may have identical signatures in Fabry-P\'{e}rot interferometry in the quantum Hall effect at filling factor 5/2. We calculate the Fano factor for the shot noise in a Mach-Zehnder interferometer in the 331 states and demonstrate that it differs from the Fano factor in the proposed non-Abelian states. The Fano factor depends periodically on the magnetic flux through the interferometer. Its maximal value is $2\times 1.4e$ for the 331 states with a symmetry between two flavors of quasiparticles. In the absence of such symmetry the Fano factor can reach $2\times 2.3e$. On the other hand, for the Pfaffian and anti-Pfaffian states the maximal Fano factor is $2\times 3.2e$. The period of the flux dependence of the Fano factor is one flux quantum. If only quasiparticles of one flavor can tunnel through the interferometer then the period drops to one half of the flux quantum. We also discuss transport signatures of a general Halperin state with the filling factor $2+k/(k+2)$.; Comment: 13 pages, 4 figures; Appendix on the states with the filling factor 2+k/(k+2) added

Mass-matrix ansatz and constraints on $B_{s}^{0}-\bar{B}_{s}^{0}$ mixing in 331 models

Martinez, R.; Ochoa, F.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 03/02/2008
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26.07%
Comparing the theoretically predicted and measured values of the mass difference of the $B^{0}_{s}$ system, we estimate the lower bound on the mass of the $Z^{\prime}$ boson of models based on the $SU(3)_{c} \otimes SU(3)_{L} \otimes U(1)_X$ gauge group. By assuming zero-texture approaches of the quark mass matrices, we find the ratio of the measured value to the theoretical prediction from the Standard Model and the $Z^{\prime}$ contribution from the 331 models of the mass difference of the $B^{0}_{s}$ system. We find lower bounds on the $Z^{\prime}$ mass ranging between 1 TeV and 30 TeV for the two most popular 331 models, and four different zero-textures ans\"atze. The above results are expressed as a function of the weak angle associated to the $b-s-Z^{\prime}$ couplings.; Comment: To be published at Physical Revew D

$Z^{\prime}$ boson signal at Tevatron and LHC in a 331 model

Gutierrez, N.; Martinez, R.; Ochoa, F.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 03/02/2008
Relevância na Pesquisa
26.07%
We analyse the possibilities to detect a new $Z^{\prime}$ boson in di-electron events at Tevatron and LHC in the framework of the 331 model with right-handed neutrinos. Using $p\bar{p}$ collision data collected by the CDF II detector at Fermilab Tevatron, we find that the 331 $Z^{\prime}$ boson is excluded with masses below 920 GeV. For an integrated luminosity of $100 fb^{-1}$ at LHC, and considering a central value $M_{Z^{\prime}}=1500$ GeV, we obtain the invariant mass distribution in the process $pp\to Z^{\prime}\to e^{+}e^{-}$, where a huge peak, corresponding to 800 signal events, is found above the SM background. The number of di-electron events vary from 10000 to 1 in the mass range of $M_{Z^{\prime}}=1000-5000$ GeV.

The Anatomy of Quark Flavour Observables in 331 Models in the Flavour Precision Era

Buras, Andrzej J.; De Fazio, Fulvia; Girrbach, Jennifer; Carlucci, Maria V.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.17%
The coming flavour precision era will allow to uncover various patterns of flavour violation in different New Physics (NP) scenarios that are presently washed out by hadronic and experimental uncertainties. We illustrate this by performing the anatomy of flavour violation in the 331 models, based on the gauge group SU(3)_C X SU(3)_L X U(1)_X that are among the simplest NP scenarios with new sources of flavour and CP violation. The latter originate dominantly through the flavour violating interactions of ordinary quarks and leptons with a new heavy Z' gauge boson. After discussing first these models in some generality, we present a detailed study of Delta F=2 observables and of rare K and B meson decays in the specific beta=1/\sqrt{3} model (to be called overline{331} model) assuming significantly smaller uncertainties in CKM and hadronic parameters than presently available. The most prominent roles in our analysis play epsilon_K, Delta M_q (q=d,s), the mixing induced CP asymmetries S_{psi K_S} and S_{psi phi}, rare decays B_{s,d}-> mu^+ mu^- and in particular the CP-asymmetry S_{mu^+ mu^-}^s in B_s ->mu^+ mu^-. We identify a number of correlations between various observables that differ from those known from CMFV models. While, the Delta F=2 observables allow still for four oases in the new parameter space...

Non-standard neutrinos interactions in a 331 model with minimum Higgs sector

Medina, M.; de Holanda, P. C.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 25/08/2011
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26.09%
We present a detailed analysis of a class of extensions to the SM Gauge chiral symmetry $SU(3)_{C}\times SU(3)_{L}\times U(1)_{X}$ (331 model), where the neutrino electroweak interaction with matter via charged and neutral current is modified through new gauge bosons of the model. We found the connections between the non-standard contributions on 331 model with non-standard interactions. Through limits of such interactions in cross section experiments we constrained the parameters of the model, obtaining that the new energy scale of this theory should obey $V>1.3$ TeV and the new bosons of the model must have masses greater than 610 GeV.; Comment: 17 Pages, latex, 1 Tables

Z and Z' decays with and without FCNC in 331 models

Carcamo, A.; Martinez, R.; Ochoa, F.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.07%
In the context of the 331 models, we consider constraints on the extra neutral boson $Z^{\prime}$ predicted by the model, where three different quark family assignments are identified. Using the ansatz of Matsuda as an specific texture for the quark mass matrices, we obtain allowed regions associated with the Z-Z' mixing angle, the mass of the $Z^{\prime}$ boson and the parameter $\beta$ which determines different 331 models. The $Z_{1}$ and $Z_{2}$ decays with and without flavor changing are also considered. The flavor changing decays of the $Z_{1}$ boson into quarks at tree level are highly suppressed by the $Z-Z^{\prime}$ mixing angle, obtaining the same order of magnitude as the standard model prediction at one loop level. The $% Z_{2}$ decay widths are calculated with and without flavor changing, where oblique radiative corrections at one loop accounts for about $1%-4%$ deviations.; Comment: 33 pages, 6 figures, LaTeX2e

Decay $t-> c\gamma$ in models with SU_L(3)XU_X(1) gauge symmetry

Cortés-Maldonado, I.; Hernández-Tomé, G.; Tavares-Velasco, G.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.14%
The one-loop level mediated $t-> c \gamma$ decay is analyzed in the framework of 331 models, which induce three-level flavor-changing neutral currents mediated by an extra neutral gauge boson, Z', and a neutral scalar boson, \phi. These models also predict new charged gauge and scalar bosons, together with three new quarks, which can be exotic (with electric charges of -4/3e and 5/3e) or standard model like. Apart from the contribution of the W boson, the $t\to c\gamma$ decay receives contributions induced by the extra gauge boson and the neutral scalar boson, which are generic for 331 models. In the so-called minimal 331 model, there are additional contributions from the new charged gauge and scalar bosons accompanied by the exotic quarks. We present analytical results for the most general $t-> c\gamma$ amplitude in terms of transcendental functions. For the numerical analysis we focus on the minimal 331 model: the current bounds on the model parameters are examined and a particular scenario is discussed in which the corresponding branching ratio could be of the order of 10^{-6}, with the dominant contributions arising from the charged gauge bosons and a relatively light neutral scalar boson with flavor-changing couplings, whereas the Z' contribution would be of the order of 10^{-9} for m_{Z'}>2 TeV. However...

Connection of $g-2_{\mu}$, electroweak, dark matter, and collider constraints on 331 models

Kelso, Chris; Long, H. N.; Martinez, R.; Queiroz, Farinaldo S.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.25%
In this work we compute all contributions to the muon magnetic moment stemming from several 3-3-1 models namely, minimal 331, 331 with right handed neutrinos, 331 with heavy neutral leptons, 331 with charged exotic leptons, 331 economical and 331 with two higgs triplets. Further, we exploit the complementarity among current electroweak, dark matter and collider constraints to outline the relevant parameter space of the models capable of explaining the anomaly. Lastly, assuming that the experimental anomaly has been otherwise resolved, we derive robust $1\sigma$ bounds using the current and projected measurements.; Comment: 13 pages, 7 figures. To appear in Phys. Rev. D

Z-Z' Mixing and Z-Mediated FCNCs in SU(3)_C x SU(3)_L x U(1)_X Models

Buras, Andrzej J.; De Fazio, Fulvia; Girrbach-Noe, Jennifer
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.16%
Most of the existing analyses of FCNC processes in the 331 models, based on the gauge group SU(3)_C x SU(3)_L x U(1)_X, take only into account tree-level exchanges of a new heavy neutral gauge boson Z'. However due to the Z-Z' mixing also corresponding contributions from Z boson are present that are usually neglected. We calculate the impact of these contributions on Delta F=2 processes and rare K, B_s and B_d decays for different values of a parameter beta, which distinguishes between various 331 models and for different fermion representations under the SU(3)_L group. We find a general expression for the Z-Z' mixing in terms beta, M_Z, M_Z' and tan(bar{beta}), familiar from 2 Higgs Doublet models, that differs from the one quoted in the literature. We study in particular the models with beta=+-n/sqrt{3} with n=1,2 which have recently been investigated by us in the context of new data on B_{s,d}->mu^+ mu^- and B_d->K^*(K)mu^+ mu^-. We find that these new contributions can indeed be neglected in the case of Delta F=2 transitions and decays, like B_d->K^*mu^+mu^-, where they are suppressed by the small vectorial Z coupling to charged leptons. However the contributions of tree-level Z exchanges to decays sensitive to axial-vector couplings...