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The globular cluster kinematics and galaxy dark matter content of NGC 3923

Norris, Mark A.; Gebhardt, Karl; Sharples, Ray M.; Raul Faifer, Favio; Bridges, Terry; Forbes, Duncan A.; Forte, Juan C.; Zepf, Stephen E.; Beasley, Michael A.; Hanes, David A.; Proctor, Robert; Kannappan, Sheila J.
Fonte: WILEY-BLACKWELL; MALDEN Publicador: WILEY-BLACKWELL; MALDEN
Tipo: Artigo de Revista Científica
Português
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This paper presents further results from our spectroscopic study of the globular cluster (GC) system of the group elliptical NGC 3923. From observations made with the GMOS instrument on the Gemini South Telescope, an additional 50 GC and ultra-compact dwarf (UCD) candidates have been spectroscopically confirmed as members of the NGC 3923 system. When the recessional velocities of these GCs are combined with the 29 GC velocities reported previously, a total sample of 79 GC/UCD velocities is produced. This sample extends to over 6 arcmin (>6 R-e similar to 30 kpc) from the centre of NGC 3923 and is used to study the dynamics of the GC system and the dark matter content of NGC 3923. It is found that the GC system of NGC 3923 displays no appreciable rotation, and that the projected velocity dispersion is constant with radius within the uncertainties. The velocity dispersion profiles of the integrated light and GC system of NGC 3923 are indistinguishable over the region in which they overlap. We find some evidence that the diffuse light and GCs of NGC 3923 have radially biased orbits within similar to 130 arcsec. The application of axisymmetric orbit-based models to the GC and integrated light velocity dispersion profiles demonstrates that a significant increase in the mass-to-light ratio (from M/L-V = 8 to 26) at large galactocentric radii is required to explain this observation. We therefore confirm the presence of a dark matter halo in NGC 3923. We find that dark matter comprises 17.5(-4.5)(+7.3) per cent of the mass within 1 R-e...

Integralidade: um estudo a partir da atenção básica à saúde da criança em modelos assistenciais distintos.; A study about the basic attendance on child’s health in different assistance models.

Prado, Sonia Regina Leite de Almeida
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 19/09/2005 Português
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O sistema de saúde do Brasil, enquanto aparato jurídico-legal, é sem dúvida um dos mais avançados do mundo, porém quando se contextualizam as dimensões sócio-culturais, políticas e econômicas onde esse sistema se concretiza, surgem contradições de diversas ordens. Avançar na consolidação do Sistema Único de Saúde - SUS implica a busca de novos mecanismos que convirjam na superação de dificuldades inerentes à nossa realidade social. Um dos mais importantes mecanismos rumo a essa direção tem sido a construção de modelos assistenciais favorecedores da efetivação dos princípios do SUS. É nesse novo contexto de diferentes formas de organização da assistência que surgem indagações com relação à qualidade da atenção básica prestada na rede pública. Buscando uma melhor delimitação do problema, elegeu-se o princípio da integralidade como um atributo essencial na qualidade do cuidado prestado e quatro dimensões da integralidade foram consideradas para sua análise: fatores contextuais, organização dos serviços / modelos assistenciais, prática da integralidade no cuidado prestado e efeito dos cuidados prestados sobre a saúde da criança. Buscando avaliar, na atenção básica prestada à saúde da criança...

Avaliação dos parâmetros CTOD e integral J em juntas soldadas utilizando corpos-de-prova compactos C(T).; CTOD and J integral parameter assessment of steel weldments using compact specimen geometry.

Savioli, Rafael Guimarães
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 04/11/2011 Português
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Este trabalho visa o refinamento do procedimento para estimativa dos parâmetros elasto-plásticos de tenacidade à fratura, integral J e CTOD, incorporando o efeito de dissimilaridade mecânica devido à introdução de juntas soldadas utilizando a metodologia eta, tal efeito não é previsto na formulação das atuais normas de avaliação de tenacidade à fratura, porém a dissimilaridade mecânica afeta fortemente a relação entre o carregamento global do espécime e as forças motrizes na ponta da trinca. Para o desenvolvimento das análises foi empregada a geometria normalizada C(T), compacta, pois esta pode apresentar potencias vantagens sobre a geometria SE(B), flexão três pontos, como menor consumo de material para a confecção dos espécimes, menor capacidade do aparato experimental e fácil manipulação na prática dos testes laboratoriais, porém carece de fatores eta quando comparados ao tradicional espécime SE(B). Os principais objetivos deste trabalho são gerar um compêndio de fatores eta e propor uma formulação robusta que incorpore os efeitos de dissimilaridade mecânica para o cálculo de integral J e CTOD. Para tal intento a matriz de análise deste trabalho abrange diferentes comprimentos de trinca, níveis de dissimilaridade mecânica e larguras de cordão de solda...

A study of the errors of the averaged models in the restricted three-body problem in a short time scale

Domingos, R. C.; Almeida Prado, A. F. B. de; Vilhena de Moraes, R.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 507-520
Português
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37.39017%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Processo FAPESP: 2011/09310-7; Processo FAPESP: 2012/21023-6; Processo FAPESP: 2011/08171-3; The objective of the present research is to study the accuracy of the double- and single-averaged models that are usually considered to predict the motion of spacecrafts or celestial bodies that have their motion perturbed by a third-body. Those two models are compared with each other and then validated against the complete elliptic restricted three-body problem. Those models are developed to give a faster but general behaviour of the motion of the perturbed body in a medium or longer time scale. The researches performed here verify the accuracy of those methods for shorter time scales by showing the differences in terms of the values of the inclination and eccentricity of the perturbed body predicted by those models. Those differences are calculated both at every instant of time and as an integral over the time. The use of the integral along the time for the errors is a new form to study those differences and show a more complete comparison of the accuracy of those approximations...

Estado actual del producto: ortodoncia integral en las clínicas global dental y propuesta estratégica para su reposicionamiento; Current status of the product: comprehensive orthodontic in global dental clinics and strategic proposal for repositioning

Muñoz Rodríguez, Martha Lucía; García Carvajal, Santiago
Fonte: Universidad Militar Nueva Granada; Facultad de Estudios a Distancia; Especialización en Alta Gerencia Publicador: Universidad Militar Nueva Granada; Facultad de Estudios a Distancia; Especialización en Alta Gerencia
Tipo: bachelorThesis; Trabajo de grado Formato: pdf; pdf
Português
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36.93044%
La investigación tuvo como objetivo Proponer un conjunto de estrategias para reposicionar el producto de ortodoncia integral ofertada por las Clínicas Global Dental Ecuador, mediante un análisis diagnóstico de mercado y una valoración de los niveles de satisfacción de sus usuarios, para lo cual se recabó información de 988 pacientes mediante un cuestionario.Se empleó el paquete estadístico SPSS para analizar la información, determinándose como resultados más importantes que 3 de cada 4 pacientes que fueron diagnosticados en las clínicas como pacientes que requieren de ortodoncia, no las toman en Global Dental, siendo el precio la principal causa de su deserción.; Research was conducted that aimed to propose a set of strategies to reposition Comprehensive Orthodontic Products offered by Global Dental Clinics of Ecuador, through a diagnostic market analysis and an assessment of the levels of user satisfaction, for which information was collected 988 patients using a questionnaire.SPSS was used to analyze the data, determined as more important than 3 out of 4 patients who were diagnosed in clinics as patients requiring orthodontic not take Global Dental results, price being the main cause of their desertion.

Three-integral multi-component dynamical models and simulations of the nuclear star cluster in NGC 4244

De Lorenzi, F.; Hartmann, M.; Debattista, V. P.; Seth, A. C.; Gerhard, O.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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Adaptive optics observations of the flattened nuclear star cluster in the nearby edge-on spiral galaxy NGC 4244 using the Gemini Near-Infrared Integral Field Spectrograph (NIFS) have revealed clear rotation. Using these kinematics plus 2MASS photometry we construct a series of axisymmetric two-component particle dynamical models with our improved version of NMAGIC, a flexible Chi^2-made-to-measure code. The models consist of a nuclear cluster disc embedded within a spheroidal particle population. We find a mass for the nuclear star cluster of M=1.6^+0.5_-0.2 x 10^7 M_sun within ~42.4 pc (2"). We also explore the presence of an intermediate mass black hole and show that models with a black hole as massive as M_bh = 5.0 x 10^5 M_sun are consistent with the available data. Regardless of whether a black hole is present or not, the nuclear cluster is vertically anisotropic (beta_z < 0), as was found with earlier two-integral models. We then use the models as initial conditions for N-body simulations. These simulations show that the nuclear star cluster is stable against non-axisymmetric perturbations. We also explore the effect of the nuclear cluster accreting star clusters at various inclinations. Accretion of a star cluster with mass 13% that of the nuclear cluster is already enough to destroy the vertical anisotropy...

Candidates for dark matter in the ${SU}(3)_C {SU}(3)_L {U}(1)_N$ models

long, H. N.; Lan, N. Q.; Soa, D. V.; Thuc, L. N.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/11/2006 Português
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It has recently been pointed out that the 511 keV emission line detected by INTEGRAL/SPI from the bulge of our galaxy could be explained by annihilations of light dark matter particles into $e^+ e^-$. We present the possibility that dark matter could be made of scalar candidates, namely, of the Higgs bosons in the models based on ${SU}(3)_C\otimes {SU}(3)_L \otimes {U}(1)_N$ (3-3-1) gauge group. These particles are singlet of the ${SU}(2)_L \otimes {U}(1)_Y$ group, so they do not interact with the ordinary particles, exept the Higgs boson in the standard model. The Spergel-Steinhardt condition for self-interacting dark matter gives a bound on the mass of the candidates to be a few MeVs. Besides the scalar candidates, which exist in both non-SUSY and SUSY 3-3-1 models with right-handed neutrinos, the spin $\fr 1 2$ candidate exists in a variant 3-3-1 version with exotic neutral lepton. In contrast to the singlet models, where an extra symmetry must be imposed to account the stability of the dark matter, here the decay of the candidates is automatically forbidden in all orders of perturbative expansion. This is because of the following feature: these scalars are singlets, i.e., in bottom of the Higgs triplet. Therefore, the standard model fermions and the standard gauge bosons cannot couple with them.; Comment: 22 pages

Improved evidence for a black hole in M32 from HST/FOS spectra - II. Axisymmetric dynamical models

van der Marel, R. P.; Cretton, N.; de Zeeuw, P. T.; Rix, H. W.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 12/05/1997 Português
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Axisymmetric dynamical models are constructed for the E3 galaxy M32 to interpret high spatial resolution stellar kinematical HST data. Models are studied with two-integral phase-space distribution functions, and with fully general three- integral distribution functions. The latter are built using a new extension of Schwarzschild's orbit superposition approach. Models are constructed for inclinations of 90 and 55 degrees. No model without a nuclear dark object can fit the combined ground-based and HST data, independent of the dynamical structure of M32. Models with a nuclear dark object of 3.4 x 10^6 solar masses do provide an excellent fit. The inclined models provide the best fit, but the inferred dark mass does not depend sensitively on the assumed inclination. The models that best fit the data are not two-integral models, but like two-integral models they are azimuthally anisotropic. An extended dark object can fit the data only if its half-mass radius is r_h < 0.08 arcsec (=0.26 pc), implying a central dark matter density exceeding 1 x 10^8 solar masses / pc^3. This density is high enough to rule out most plausible alternatives to a massive black hole. The dynamically inferred dark mass is identical to that suggested by existing adiabatic black hole growth models for HST photometry of M32. The low activity of M32 implies either that only a very small fraction of the gas that is shed by evolving stars is accreted onto the black hole...

Efficient Topological Compilation for Weakly-Integral Anyon Model

Bocharov, Alex; Cui, Shawn X.; Kliuchnikov, Vadym; Wang, Zhenghan
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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In a recent series of two research papers Cui, Wang and Hong proposed a class of anyonic models for universal quantum computation based on weakly-integral anyons. While universal set of gates cannot be obtained in this context by anyon braiding alone, designing a certain type of sector charge measurement provides universality. From the mathematical standpoint the underlying unitary bases arising in various versions of the weakly-integral anyonic models are defined over a certain ring of Eisenstein rationals, that has useful number-theoretic properties. In this paper we develop a compilation algorithm to approximate arbitrary $n$-qutrit unitaries with asymptotically efficient circuits over the metaplectic anyon model, the most recent instance of the weakly-integral anyonic class. One flavor of our algorithm produces efficient circuits with upper complexity bound asymptotically in $O(3^{2\,n} \, \log{1/\varepsilon})$ and entanglement cost that is exponential in $n$. Another flavor of the algorithm produces efficient circuits with upper complexity bound in $O(n\,3^{2\,n} \, \log{1/\varepsilon})$ and no additional entanglement cost.; Comment: 15 pages, 3 figures

The Low End of the Supermassive Black Hole Mass Function: Constraining the Mass of a Nuclear Black Hole in NGC 205 via Stellar Kinematics

Valluri, Monica; Ferrarese, Laura; Merritt, David; Joseph, Charles L.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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Hubble Space Telescope (HST) images and spectra of the nucleated dwarf elliptical galaxy NGC 205 are combined with 3-integral axisymmetric dynamical models to constrain the mass (M_BH) of a putative nuclear black hole. This is only the second attempt, after M33, to use resolved stellar kinematics to search for a nuclear black hole with mass below 10^6 solar masses. We are unable to identify a best-fit value of M_BH in NGC 205; however, the data impose a upper limit of 2.2x10^4 M_sun (1sigma confidence) and and upper limit of 3.8x10^4 M_sun (3sigma confidence). This upper limit is consistent with the extrapolation of the M_BH-sigma relation to the M_BH < 10^6 M_sunregime. If we assume that NGC 205 and M33 both contain nuclear black holes, the upper limits on M_BH in the two galaxies imply a slope of ~5.5 or greater for the M_BH-sigma relation. We use our 3-integral models to evaluate the relaxation time (T_r) and stellar collision time (T_coll) in NGC 205; T_r~10^8 yr or less in the nucleus and T_coll~10^11 yr. The low value of T_r is consistent with core collapse having already occurred, but we are unable to draw conclusions from nuclear morphology about the presence or absence of a massive black hole.; Comment: Latex emulateapj, 15 pages...

Dynamical stability of N-body models for M32 with a central black hole

van der Marel, R. P.; Sigurdsson, S.; Hernquist, L.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/02/1997 Português
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We study the stability of stellar dynamical equilibrium models for M32. Kinematic observations show that M32 has a central black hole of 3x10^6 solar masses, and a phase-space distribution function that is close to the `two-integral' form f=f(E,L_z). M32 is also rapidly rotating; 85-90% of the stars have the same sense of rotation around the symmetry axis. Previous work has shown that flattened, rapidly rotating two-integral models can be bar-unstable. We have performed N-body simulations to test whether this is the case for M32. Particle realizations with N=512,000 were studied for two representative inclinations, i=90 (edge-on) and i=55, corresponding to intrinsic axial ratios of q=0.73 and q=0.55, respectively. The time evolution of the models was calculated with a `self-consistent field' code on a Cray T3D parallel supercomputer. We find both models to be dynamically stable. This implies that they provide a physically meaningful description of M32, and that the inclination of M32 (and hence its intrinsic flattening) cannot be strongly constrained through stability arguments. Previous work on the stability of f(E,L_z) models has shown that the bar-mode is the only possibly unstable mode for systems rounder than q=0.3, and that the likelihood for this mode to be unstable increases with flattening and rotation rate. The f(E...

The Three-Dimensional Mass Distribution in NGC 1700

Statler, Thomas S.; Dejonghe, Herwig; Smecker-Hane, Tammy
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 02/10/1998 Português
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A variety of modeling techniques is used with surface photometry from the literature and recently acquired high-accuracy stellar kinematic data to constrain the three-dimensional mass distribution in the luminous cuspy elliptical galaxy NGC 1700. First, we model the radial velocity field and photometry, and, using a Bayesian technique, estimate the triaxiality T and short-to-long axis ratio c in five concentric annuli between approximately 1 and 3 effective radii. The results are completely consistent with T being constant inside about 2.5 r_e (36 arcsec; 6.7/h kpc). Adding an assumption of constant T as prior information gives an upper limit of T < 0.16 (95% confidence); this relaxes to T < 0.22 if it is also assumed that there is perfect alignment between the angular momentum and the galaxy's intrinsic short axis. Near axisymmetry permits us then to use axisymmetric models to constrain the radial mass profile. Using the Jeans (moment) equations, we demonstrate that 2-integral, constant-M/L models cannot fit the data; but a 2-integral model in which the cumulative enclosed M/L increases by a factor of roughly 2 from the center out to 12/h kpc can. Three-integral models constructed by quadratic programming show that, in fact, no constant-M/L model is consistent with the kinematics. Anisotropic 3-integral models with variable M/L...

Axisymmetric, 3-Integral Models of Galaxies: A Massive Black Hole in NGC3379

Gebhardt, Karl; Richstone, Douglas; Kormendy, John; Lauer, Tod; Ajhar, Edward; Bender, Ralf; Dressler, Alan; Faber, Sandra; Grillmair, Carl; Magorrian, John; Tremaine, Scott
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/12/1999 Português
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We fit axisymmetric 3-integral dynamical models to NGC3379 using the line-of-sight velocity distribution obtained from HST/FOS spectra of the galaxy center and ground-based long-slit spectroscopy along four position angles, with the light distribution constrained by WFPC2 and ground-based images. We have fitted models with inclinations from 29 (intrinsic galaxy type E5) to 90 degrees (intrinsic E1) and black hole masses from 0 to 1e9 M_solar. The best-fit black hole masses range from 6e7 to 2e8 M_solar, depending on inclination. The velocity ellipsoid of the best model is not consistent with either isotropy or a two-integral distribution function. Along the major axis, the velocity ellipsoid becomes tangential at the innermost bin, radial in the mid-range radii, and tangential again at the outermost bins. For the acceptable models, the radial to tangential dispersion in the mid-range radii ranges from 1.1 < sigma_r / sigma_t < 1.7. Compared with these 3-integral models, 2-integral isotropic models overestimate the black hole mass since they cannot provide adequate radial motion. However, the models presented in this paper still contain restrictive assumptions-namely assumptions of constant M/L and spheroidal symmetry-requiring yet more models to study black hole properties in complete generality.; Comment: 15 pages...

On the reliability of the black hole mass and mass to light ratio determinations with Schwarzschild models

Cretton, N.; Emsellem, E.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/12/2003 Português
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In this Letter, we investigate the claim of Valluri et al. (2003), namely that the use of Schwarzschild dynamical (orbit-based) models leads to an indeterminacy regarding the estimation of the free parameters like the central black hole mass and the stellar mass-to-light ratio of the galaxy under study. We examine this issue with semi-analytic two-integral models, which are not affected by the intrinsic degeneracy of three-integral systems. We however confirm the Valluri et al. result, and observe the so-called widening of the chi2 contours as the orbit library is expanded. We also show that, although two-dimensional data coverage help in constraining the orbital structure of the modelled galaxy, it does not in principle solve the indeterminacy issue, which mostly originates from the discretization of such an inverse problem. We show that adding regularization constraints stabilizes the confidence level contours on which the estimation of black hole mass and stellar mass-to-light ratio are based. We therefore propose to systematically use regularization as a tool to prevent the solution to depend on the orbit library. Regularization, however, introduces an unavoidable bias on the derived solutions. We hope that the present Letter will trigger some more research directed at a better understanding of the issues addressed here.; Comment: 5 pages...

The Black Hole in NGC 3379: A Comparison of Gas and Stellar Dynamical Mass Measurements with HST and Integral-Field Data

Shapiro, Kristen L.; Cappellari, Michele; de Zeeuw, Tim; McDermid, Richard M.; Gebhardt, Karl; Bosch, Remco C. E. van den; Statler, Thomas S.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/05/2006 Português
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We combine Hubble Space Telescope spectroscopy and ground-based integral-field data from the SAURON and OASIS instruments to study the central black hole in the nearby elliptical galaxy NGC 3379. From these data, we obtain kinematics of both the stars and the nuclear gaseous component. Axisymmetric three-integral models of the stellar kinematics find a black hole of mass 1.4 (+2.6 / -1.0) x 10^8 M_sun (3 sigma errors). These models also probe the velocity distribution in the immediate vicinity of the black hole and reveal a nearly isotropic velocity distribution throughout the galaxy and down to the black hole sphere of influence R_BH. The morphology of the nuclear gas disc suggests that it is not in the equatorial plane; however the core of NGC 3379 is nearly spherical. Inclined thin-disc models of the gas find a nominal black hole of mass 2.0 (+/- 0.1) x 10^8 M_sun (3 sigma errors), but the model is a poor fit to the kinematics. The data are better fit by introducing a twist in the gas kinematics (with the black hole mass assumed to be 2.0 x 10^8 M_sun), although the constraints on the nature and shape of this perturbation are insufficient for more detailed modelling. Given the apparent regularity of the gas disc's appearance, the presence of such strong non-circular motion indicates that caution must be used when measuring black hole masses with gas dynamical methods alone.; Comment: 22 pages...

Projective integral models of Shimura varieties of Hodge type with compact factors

Vasiu, Adrian
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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Let $(G,X)$ be a Shimura pair of Hodge type such that $G$ is the Mumford--Tate group of some elements of $X$. We assume that for each simple factor $G_0$ of $G^{\ad}$ there exists a simple factor of $G_{0\dbR}$ which is compact. Let $N\Ge 3$. We show that for many compact open subgroups $K$ of $G(\dbA_f)$, the Shimura variety $\Sh(G,X)/K$ has a projective integral model $\scrN$ over $\dbZ[{1\over N}]$ which is a finite scheme over a certain Mumford moduli scheme $\scrA_{g,1,N}$. Equivalently, we show that if $A$ is an abelian variety over a number field and if the Mumford--Tate group of $A_{\dbC}$ is $G$, then $A$ has potentially good reduction everywhere. The last result represents significant progress towards the proof of a conjecture of Morita. If $\scrN$ is smooth over $\dbZ[{1\over N}]$, then it is a N\'eron model of its generic fibre. In this way one gets in arbitrary mixed characteristic, the very first examples of general nature of projective N\'eron models whose generic fibres are not finite schemes over abelian varieties.; Comment: 24 pages, final version accepted for publication in Crelle

Multiple integral formulae for the scalar product of on-shell and off-shell Bethe vectors in SU(3)-invariant models

Wheeler, M
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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We study the scalar product S_{l,m} between an on-shell and an off-shell Bethe state in models with SU(3)-invariance, where l and m denote the cardinalities of the two sets of Bethe roots. We construct recursion relations relating S_{l,m} to scalar products of smaller dimension, namely S_{l-1,m} and S_{l,m-1}. Solving these recursion relations we obtain new multiple integral expressions for S_{l,m}, whose integrands are (l+m) \times (l+m) determinants, and closely related to the Slavnov determinant expression for the SU(2) scalar product.; Comment: 19 pages, 5 figures, a reference added in v2

Integral Models of $X_0(N)$ and Their Degrees

c, Goran Mui\'
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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In this paper we compute the degree of a curve which is the image of a mapping $z\longmapsto (f(z): g(z): h(z))$ constructed out of three linearly independent modular forms of the same even weight $\ge 4$ into $\mathbb P^2$. We prove that in most cases this map is a birational equivalence and defined over $\mathbb Z$. We use this to construct models of $X_0(N)$, $N\ge 2$, using modular forms in $M_{12}(\Gamma_0(N))$ with integral $q$--expansion. The models have degree equal to $\psi(N)$ (a classical Dedekind psi function). When genus is at least one, we show the existence of models constructed using cuspidal forms in $S_4(\Gamma_0(N))$ of degree $\le \psi(N)/3$ and in $S_6(\Gamma_0(11))$ of degree 4. As an example of a different kind, we compute the formula for the total degree i.e., the degree considered as a polynomial of two (independent) variables of the classical modular polynomial (or the degree of the canonical model of $X_0(N)$).; Comment: In this version we correct Lemma 5.2 (in old version, now Lemma 5.3) making the correct formula for the total degree of the classical modular polynomial (see Theorem 1.1 in new version). We reworked the introduction a little bit and Section 5 where we compute the degree of classical modular polynomial

Models for bacteriophage systems, weak convergence of Gaussian processes and L² modulus of Brownian local time

Bascompte Viladrich, David
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis Formato: application/pdf
Publicado em //2014 Português
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En aquesta memòria es tracten tres problemes diferents. En el Capítol 1 es construeixen dues famílies de processos que convergeixen, en el sentit de les distribucions en dimensió finita, cap a dos processos Gaussians independents. El Capítol 2 està dedicat a l'estudi d'un model de tractament amb bacteriòfags per infeccions bacterianes. Finalment, en el Capítol 3, estudiem alguns aspectes del L2 mòdul de continuïtat del temps local del Brownià. En el primer capítol considerem dos processos Gaussians independents que es poden representar en termes d'una integral estocàstica d'un nucli determinista respecte el procés de Wiener, i construïm, a partir d'un únic procés de Poisson, dues famílies de processos que convergeixen, en el sentit de les distribucions en dimensió finita, cap a aquests processos Gaussians. Utilitzarem aquest resultat per a provar resultats de convergència en llei cap a altres processos, com ara el moviment Brownià sub-fraccionari. En el Capítol 2 construïm i estudiem diferents model que pretenen estudiar el comportament d'un tractament amb bacteriòfags en certs animals de granja. Aquest problema ha estat motivat pel Grup de Biologia Molecular del Departament de Genètica i Microbiologia de la Universitat Autònoma de Barcelona. Començant per un model bàsic...

The low end of the supermassive black hole mass function: constraining the mass of a nuclear black hole in NGC 205 via stellar kinematics

Valluri, Monica; Ferrarese, Laura; Merritt, David; Joseph, Charles
Fonte: Chicago University Press Publicador: Chicago University Press
Tipo: Pré-impressão Formato: 494128 bytes; application/pdf
Português
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Hubble Space Telescope (HST) images and spectra of the nucleated dwarf elliptical galaxy NGC 205 are combined with 3-integral axisymmetric dynamical models to constrain the mass MBH of a putative nuclear black hole. This is only the second attempt, after M33, to use resolved stellar kinematics to search for a nuclear black hole with mass below 106 solar masses. We are unable to identify a best-fit value of MBH in NGC 205; however, the data impose a upper limit of 2.2×104M⊙ (1σ confidence) and and upper limit of 3.8×104M⊙ (3σ confidence). This upper limit is consistent with the extrapolation of the MBH − σ relation to the MBH < 106M⊙ regime. If we assume that NGC 205 and M33 both contain nuclear black holes, the upper limits on MBH in the two galaxies imply a slope of 5.5 or greater for the MBH − σ relation. We use our 3-integral models to evaluate the relaxation time and stellar collision time in NGC 205; Tr is 108 yr or less in the nucleus and Tcoll 1011 yr. The low value of Tr is consistent with core collapse having already occurred, but we are unable to draw conclusions from nuclear morphology about the presence or absence of a massive black hole. (Refer to PDF file for exact formulas).; Also archived In: arXiv: astro-ph/0502493 v2 12 Apr 2005; This work was supported by STScI grant GO-09448 and grants AST-0206031...