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Organização de episodios de ensino sobre a "questão nuclear" para o ensino medio : foco no imaginario de licenciados; Production of theach episodes above "nuclear question" for high school : focus in the future of physics teacher imaginary

Thirza Pavan Sorpreso
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 22/02/2008 PT
Relevância na Pesquisa
55.96%
Neste trabalho procuramos compreender o imaginário de licenciandos em Física a respeito da inclusão da Física Moderna e Contemporânea no ensino médio. Acompanhamos uma turma de licenciandos em Física cursando a disciplina Prática de Ensino de Física e Estágio Supervisionado durante o primeiro semestre de 2005, no período diurno, na Faculdade de Educação da Universidade Estadual de Campinas. Dentro da temática Questão Nuclear os licenciandos prepararam episódios de ensino nos quais deveria estar presente uma das seguintes abordagens estudadas pela pesquisa em ensino de ciências: História da Ciência; Ciência, Tecnologia, Sociedade e Ambiente; Resolução de Problemas e Linguagens no Ensino de Ciências. Tendo como referencial teórico a Análise de Discurso, na vertente iniciada na França por Michel Pêcheux, com apoio principalmente em textos publicados no Brasil por Eni Puccinelli Orlandi, procuramos compreender os sentidos atribuídos pelos licenciandos para a inclusão da Física Nuclear no ensino médio. Para tal analisamos seus discursos escritos e falados nas atividades da disciplina. Pensamos o imaginário dos licenciandos como um dos aspectos condicionados pelas mediações possíveis em sala de aula e também condicionantes das mesmas. Observamos que algumas condições de produção se relacionaram com limites apontados pelos licenciandos para tal inclusão...

Energia Nuclear mediante o enfoque Ciência, Tecnologia e Sociedade na formação inicial de professores de Física; Nuclear Energy by focusing science, technology and society approach at inicial training of physics teachers

Thirza Pavan Sorpreso
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 01/11/2013 PT
Relevância na Pesquisa
55.93%
A pesquisa aqui apresentada se justifica pela necessidade de renovação de conteúdos e de formas de ensino, apontada por estudos da área de ensino de Física. Trabalhamos elementos de Física Nuclear por meio da abordagem Ciência, Tecnologia e Sociedade (CTS) em uma disciplina oferecida nos anos iniciais da licenciatura em Física. A abordagem CTS incorporou-se ao ensino a partir de movimentos extraescolares que reivindicavam uma visão mais crítica da Ciência e da Tecnologia, considerando-as como instituições não neutras, ou seja, influenciadas pelo contexto social de sua produção e de sua utilização. A abordagem CTS é utilizada neste trabalho visando a reflexões dos futuros professores de Física sobre a necessidade de rompimento com um ensino baseado apenas em cálculos e em resolução de exercícios e sobre a compreensão da Física Nuclear de forma ampla, ou seja, levando em consideração a não neutralidade da Ciência, sua produção e as complexas relações estabelecidas com a Sociedade e a Tecnologia. Para o desenvolvimento do trabalho na formação de professores, articulamos uma unidade de ensino a partir da pressuposição de um interlocutor, da escolha de conteúdos sobre a Física Nuclear e da ênfase em determinados elementos da abordagem CTS...

22.101 Applied Nuclear Physics, Fall 2004; Applied Nuclear Physics

Yip, Sidney
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
EN-US
Relevância na Pesquisa
65.92%
Fundamentals of nuclear physics for engineering students. Basic properties of the nucleus and nuclear radiations. Elementary quantum mechanical calculations of bound-state energies and barrier transmission probability. Binding energy and nuclear stability. Interactions of charged particles, neutrons, and gamma rays with matter. Radioactive decays. Energetics and general cross-section behavior in nuclear reactions. Description from course home page: This subject deals with foundational knowledge for all students in NED. Emphasis is on nuclear concepts (as opposed to traditional nuclear physics), especially nuclear radiations and their interactions with matter. We will study different types of reactions, single-collision phenomena (cross sections) and leave the effects of many collisions to later subjects (22.105 and 22.106). Quantum mechanics is used at a lower level than in 22.51 and 22.106.

8.13-14 Experimental Physics I & II "Junior Lab", Fall 2004-Spring 2005; Experimental Physics I & II "Junior Lab"

Becker, Ulrich J.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
EN-US
Relevância na Pesquisa
55.86%
Junior Lab consists of two undergraduate courses in experimental physics. The courses are offered by the MIT Physics Department, and are usually taken by Juniors (hence the name). Officially, the courses are called Experimental Physics I and II and are numbered 8.13 for the first half, given in the fall semester, and 8.14 for the second half, given in the spring. The purposes of Junior Lab are to give students hands-on experience with some of the experimental basis of modern physics and, in the process, to deepen their understanding of the relations between experiment and theory, mostly in atomic and nuclear physics. Each term, students choose 5 different experiments from a list of 21 total labs.

Despertando responsabilidade social no ensino médio por meio de temáticas associadas à física nuclear

Souza, Alcindo Mariano de
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Ensino de Ciências Naturais e Matemática; Ensino de Ciências Naturais e Matemática Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Ensino de Ciências Naturais e Matemática; Ensino de Ciências Naturais e Matemática
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
55.89%
Many discussions about the role of the school are on the agenda, in an increasingly complex society. Sociologists, educators, anthropologists, researchers of different areas seek that role. The objective of this dissertation is to contribute what we can consider the central role for the physics teaching, citizenship training. We have elaborated a didactic proposal to increase the interest of high school students on issues of social relevance and, throughout it, to promote the formation of attitudes of social responsibility, enhancing the formation of a more politically and socially active citizen. For the preparation of the proposal, studies were made on education for citizenship and on attitudes change, using as its main theoretical foundation the researches on the Science, Technology and Society curricular emphasis. The teaching of Nuclear Physics was integrated to our proposal, due to its pedagogical potential for the discussion of social, political and economic subjects related to scientific concepts and associated technologies. The educational proposal we have produced was applied on a high school class of a private school at Natal-RN. It was composed from the controversial issue involving the installation of nuclear power plants in Brazilian northeast. The methodology of role playing...

Facilities for the Energy Frontier of Nuclear Physics

Jowett, John M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/09/2011
Relevância na Pesquisa
55.89%
The Relativistic Heavy Ion Collider at BNL has been exploring the energy frontier of nuclear physics since 2001. Its performance, flexibility and continued innovative upgrading can sustain its physics output for years to come. Now, the Large Hadron Collider at CERN is about to extend the frontier energy of laboratory nuclear collisions by more than an order of magnitude. In the coming years, its physics reach will evolve towards still higher energy, luminosity and varying collision species, within performance bounds set by accelerator technology and by nuclear physics itself. Complementary high-energy facilities will include fixed-target collisions at the CERN SPS, the FAIR complex at GSI and possible electron-ion colliders based on CEBAF at JLAB, RHIC at BNL or the LHC at CERN.; Comment: Invited talk at the International Nuclear Physics Conference, Vancouver, Canada, 4-9 July 2010, to be published in Journal of Physics: Conference Series. http://inpc2010.triumf.ca/

Modern topics in theoretical nuclear physics

Jennings, B. K.; Schwenk, A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.9%
Over the past five years there have been profound advances in nuclear physics based on effective field theory and the renormalization group. In this brief, we summarize these advances and discuss how they impact our understanding of nuclear systems and experiments that seek to unravel their unknowns. We discuss future opportunities and focus on modern topics in low-energy nuclear physics, with special attention to the strong connections to many-body atomic and condensed matter physics, as well as to astrophysics. This makes it an exciting era for nuclear physics.; Comment: 8 pages, 1 figure, prepared for the Nuclear Physics Town Hall Meeting at TRIUMF, Sept. 9-10, 2005, comments welcome, references added

Perspectives of Nuclear Physics

Faessler, Amand
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 06/12/2002
Relevância na Pesquisa
55.92%
The organizers of this meeting have asked me to present perspectives of nuclear physics. This means to identify the areas where nuclear physics will be expanding in the next future. In six chapters a short overview of these areas will be given, where I expect that nuclear physics willdevelop quite fast: A. Quantum Chromodynamics and effective field theories in the confinement region; B. Nuclear structure at the limits; C. High energy heavy ion collisions; D. Nuclear astrophysics; E. Neutrino physics; F. Test of physics beyond the standard model by rare processes. After a survey over these six points I will pick out a few topics where I will go more in details. There is no time to give for all six points detailed examples. I shall discuss the following examples of the six topics mentionned above: 1. The perturbative chiral quark model and the nucleon $\Sigma$-term, 2. VAMPIR (Variation After Mean field Projection In Realistic model spaces and with realistic forces) as an example of the nuclear structure renaissance, 3. Measurement of important astrophysical nuclear reactions in the Gamow peak, 4. The solar neutrino problem. As examples for testing new physics beyond the standard model by rare processes I had prepared to speak about the measurement of the electric neutron dipole moment and of the neutrinoless double beta decay. But the time is limited and so I have to skip these points...

Nuclear physics aspects of double beta decay

Vogel, Petr
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/07/2008
Relevância na Pesquisa
55.87%
Comprehensive description of the phenomenology of the $\beta\beta$ decay is given, with emphasis on the nuclear physics aspects. After a brief review of the neutrino oscillation results and of motivation to test the lepton number conservation, the mechanism of the $0\nu\beta\beta$ is discussed. Its relation to the lepton flavor violation involving charged leptons and its use as a diagnostic tool of the $0\nu\beta\beta$ mechanism is described. Next the basic nuclear physics of both $\beta\beta$-decay modes is presented, and the decay rate formulae derived. The nuclear physics methods used, the nuclear shell model and the quasiparticle random phase approximation, are described next, and the choice of input parameters is discussed in the following section. Finally, the numerical values of the nuclear matrix elements, and their uncertainty, are presented. In the appendix the relation of the search for the neutrino magnetic moment to the Dirac versus Majorana nature of neutrinos is described.; Comment: Lecture notes for course CLXX "MEASUREMENTS OF NEUTRINO MASS" Int. School of Physics "Enrico Fermi", Varenna, June 2008

Electro and gamma nuclear physics in Geant4

Wellisch, J. P.; Kossov, M.; Degtyarenko, P.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 03/06/2003
Relevância na Pesquisa
55.93%
Adequate description of electro and gamma nuclear physics is of utmost importance in studies of electron beam-dumps and intense electron beam accelerators. I also is mandatory to describe neutron backgrounds and activation in linear colliders. This physics was elaborated in Geant4 over the last year, and now entered into the stage of practical application. In the {\sc Geant4} Photo-nuclear data base there are at present about 50 nuclei for which the Photo-nuclear absorption cross sections have been measured. Of these, data on 14 nuclei are used to parametrize the gamma nuclear reaction cross-section The resulting cross section is a complex, factorized function of $A$ and $e = log(E_\gamma)$, where $E_\gamma$ is the energy of the incident photon. Electro-nuclear reactions are so closely connected with Photo-nuclear reactions that sometimes they are often called ``Photo-nuclear''. The one-photon exchange mechanism dominates in Electro-nuclear reactions, and the electron can be substituted by a flux of photons. Folding this flux with the gamma-nuclear cross-section, we arrive at an acceptable description of the electro-nuclear physics. Final states in gamma and electro nuclear physics are described using chiral invariant phase-space decay at low gamma or equivalent photon energies...

A new tool in nuclear physics: Nuclear lattice simulations

Meißner, Ulf-G.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/05/2015
Relevância na Pesquisa
55.86%
In the last years, chiral effective field theory has been successfully developed for and applied to systems with few nucleons. Here, I present a new approach for ab initio calculations of nuclei that combines these precise and systematic forces with Monte Carlo simulation techniques that allow for exact solutions of the nuclear A-body problem. A short introduction of this method is given and a few assorted results concerning the spectrum and structure of 12C and 16O are presented. The framework further allows one to study the properties of nuclei in worlds that have fundamental parameters different from the ones in Nature. This allows for a physics test of the anthropic principle by addressing the question how strongly the generation of the life-relevant elements depends on the light quark masses and the electromagnetic fine structure constant.; Comment: commissioned article for Nuclear Physics News

Degeneracies of particle and nuclear physics uncertainties in neutrinoless double beta decay

Lisi, E.; Rotunno, A.; Simkovic, F.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.87%
Theoretical estimates for the half life of neutrinoless double beta decay in candidate nuclei are affected by both particle and nuclear physics uncertainties, which may complicate the interpretation of decay signals or limits. We study such uncertainties and their degeneracies in the following context: three nuclei of great interest for large-scale experiments (76-Ge, 130-Te, 136-Xe), two representative particle physics mechanisms (light and heavy Majorana neutrino exchange), and a large set of nuclear matrix elements (NME), computed within the quasiparticle random phase approximation (QRPA). It turns out that the main theoretical uncertainties, associated with the effective axial coupling g_A and with the nucleon-nucleon potential, can be parametrized in terms of NME rescaling factors, up to small residuals. From this parametrization, the following QRPA features emerge: (1) the NME dependence on g_A is milder than quadratic; (2) in each of the two mechanisms, the relevant lepton number violating parameter is largely degenerate with the NME rescaling factors; and (3) the light and heavy neutrino exchange mechanisms are basically degenerate in the above three nuclei. We comment on the challenging theoretical and experimental improvements required to reduce such particle and nuclear physics uncertainties and their degeneracies.; Comment: 11 pages...

Symmetry and Supersymmetry in Nuclear Physics

Balantekin, A. B.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/11/2007
Relevância na Pesquisa
55.86%
A survey of algebraic approaches to various problems in nuclear physics is given. Examples are chosen from pairing of many-nucleon systems, nuclear structure, fusion reactions below the Coulomb barrier, and supernova neutrino physics to illustrate the utility of group-theoretical and related algebraic methods in nuclear physics.; Comment: 23 pages of Latex (requires cimento.cls which is included). Proceedings of the "Enrico Fermi" Summer School - Nuclear Structure far from Stability: New Physics and New Technology

Nuclear physics from QCD on lattice

Inoue, Takashi; Collaboration, for HAL QCD
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.87%
We have presented a strategy to study nuclei and nuclear matters from the 1st principle, QCD. We first compute nucleon-nucleon potentials numerically in lattice QCD, and then use them to investigate properties of nuclei and the matters by various method developed in nuclear physics. As the demonstration for this strategy to work, mass and structure of 4^He, 16^O and 40^Ca, and equation of state of nuclear matters are determined with the lattice QCD induced two-nucleon potentials in a heavy quark region as an input. We have found that these nuclei and the symmetric nuclear matter are bound at one quark mass corresponding to the pseudo-scalar meson (pion) mass of 469 MeV (the octet baryon (nucleon) mass of 1161 MeV). Obtained binding energy per nucleon has a uniform mass number A dependence which is consistent to the Bethe-Weizsacker mass formula qualitatively. The present study demonstrates that our strategy works well to investigate various properties of atomic nuclei and nuclear matters starting from QCD, without depending on models or experimental information of nuclear force.; Comment: 20 pages, 15 figures, proceedings of the 8th International Workshop on Chiral Dynamics, 29 June - 3 July 2015, Pisa, Italy

Quantum Monte Carlo methods for nuclear physics

Carlson, J.; Gandolfi, S.; Pederiva, F.; Pieper, Steven C.; Schiavilla, R.; Schmidt, K. E.; Wiringa, R. B.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.86%
Quantum Monte Carlo methods have proved very valuable to study the structure and reactions of light nuclei and nucleonic matter starting from realistic nuclear interactions and currents. These ab-initio calculations reproduce many low-lying states, moments and transitions in light nuclei, and simultaneously predict many properties of light nuclei and neutron matter over a rather wide range of energy and momenta. We review the nuclear interactions and currents, and describe the continuum Quantum Monte Carlo methods used in nuclear physics. These methods are similar to those used in condensed matter and electronic structure but naturally include spin-isospin, tensor, spin-orbit, and three-body interactions. We present a variety of results including the low-lying spectra of light nuclei, nuclear form factors, and transition matrix elements. We also describe low-energy scattering techniques, studies of the electroweak response of nuclei relevant in electron and neutrino scattering, and the properties of dense nucleonic matter as found in neutron stars. A coherent picture of nuclear structure and dynamics emerges based upon rather simple but realistic interactions and currents.; Comment: 57 pages, 40 figures, accepted for publication in Reviews of Modern Physics

Current Status of Nuclear Physics Research

Bertulani, C. A.; Hussein, M. S.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.88%
In this review we discuss the current status of research in nuclear physics which is being carried out in different centers in the World. For this purpose we supply a short account of the development in the area which evolved over the last 9 decades, since the discovery of the neutron. The evolution of the physics of the atomic nucleus went through many stages as more data become available. We briefly discuss models introduced to discern the physics behind the experimental discoveries, such as the shell model, the collective model, the statistical model, the interacting boson model, etc., some of these models may be seemingly in conflict with each other, but this was shown to be only apparent. The richness of the ideas and abundance of theoretical models attests to the important fact that the nucleus is a really singular system in the sense that it evolves from two-body bound states such as the deuteron, to few-body bound states, such as $^4$He, $^7$Li, $^9$Be etc. and up the ladder to heavier bound nuclei containing up to more than 200 nucleons. Clearly statistical mechanics does not work for such finite system, neither does other theories applicable to condensed matter systems. The richness of nuclear physics stems from these restrictions. New theories and models are presently being developed. Theories of the structure and reactions of neutron-rich and proton-rich nuclei...

Fractional Authorship in Nuclear Physics

Pritychenko, B.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 25/09/2015
Relevância na Pesquisa
55.88%
Large, multi-institutional groups or collaborations of scientists are engaged in nuclear physics research projects, and the number of research facilities is dwindling. These collaborations have their own authorship rules, and they produce a large number of highly-cited papers. Multiple authorship of nuclear physics publications creates a problem with the assessment of an individual author's productivity relative to his/her colleagues and renders ineffective a performance metrics solely based on annual publication and citation counts. Many institutions are increasingly relying on the total number of first-author papers; however, this approach becomes counterproductive for large research collaborations with an alphabetical order of authors. A concept of fractional authorship (the claiming of credit for authorship by more than one individual) helps to clarify this issue by providing a more complete picture of research activities. In the present work, nuclear physics fractional and total authorships have been investigated using nuclear data mining techniques. Historic total and fractional authorship averages have been extracted from the Nuclear Science References (NSR) database, and the current range of fractional contributions has been deduced. The results of this study and their implications are discussed and conclusions presented.; Comment: 8 pages...

Probing particle and nuclear physics models of neutrinoless double beta decay with different nuclei

Fogli, G. L.; Lisi, E.; Rotunno, A. M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.87%
Half-life estimates for neutrinoless double beta decay depend on particle physics models for lepton flavor violation, as well as on nuclear physics models for the structure and transitions of candidate nuclei. Different models considered in the literature can be contrasted - via prospective data - with a "standard" scenario characterized by light Majorana neutrino exchange and by the quasiparticle random phase approximation, for which the theoretical covariance matrix has been recently estimated. We show that, assuming future half-life data in four promising nuclei (Ge-76, Se-82, Te-130, and Xe-136), the standard scenario can be distinguished from a few nonstandard physics models, while being compatible with alternative state-of-the-art nuclear calculations (at 95% C.L.). Future signals in different nuclei may thus help to discriminate at least some decay mechanisms, without being spoiled by current nuclear uncertainties. Prospects for possible improvements are also discussed.; Comment: Minor corrections in the text, references added. Matches published version in Phys. Rev. D 80, 015024 (2009)

Nuclear Physics from Lattice Quantum Chromodynamics

Savage, Martin J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 06/10/2015
Relevância na Pesquisa
55.89%
Quantum Chromodynamics and Quantum Electrodynamics, both renormalizable quantum field theories with a small number of precisely constrained input parameters, dominate the dynamics of the quarks and gluons - the underlying building blocks of protons, neutrons, and nuclei. While the analytic techniques of quantum field theory have played a key role in understanding the dynamics of matter in high energy processes, they encounter difficulties when applied to low-energy nuclear structure and reactions, and dense systems. Expected increases in computational resources into the exascale during the next decade will provide the ability to determine a range of important strong interaction processes directly from QCD using the numerical technique of Lattice QCD. This will complement the nuclear physics experimental program, and in partnership with new thrusts in nuclear many-body theory, will enable unprecedented understanding and refinement of nuclear forces and, more generally, the visible matter in our universe. In this presentation, I will discuss the state-of-the-art Lattice QCD calculations of quantities of interest in nuclear physics, progress that is expected in the near future, and the anticipated impact.; Comment: Talk presented at the Twelfth Conference on the Intersections of Particle and Nuclear Physics...

Nuclear Physics --- at the frontiers of knowledge

Feshbach, Herman
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 10/10/1995
Relevância na Pesquisa
55.87%
(transcript of a talk given by Prof.~Feshbach:) Nuclear physics has been and will be a major factor in science and technology. It makes unique and important contributions to medicine, to industry and to other sciences. Interaction with other physics has been strong. Astrophysics and mesoscopic physics are notable examples. But what I shall talk about today are labeled {\bf``universals"}. This refers to results which transcend the limits of a given subject providing fundamental principles which inform not only nuclear physics but all of science. It is the universals which take nuclear physics research from the parochial albeit fascinating studies of nuclear reactions and structure to the development and formulation of concepts of significance for all of the physical sciences.; Comment: 9 pages in LaTeX. (Hardcopy of 21 figs can be requested via email.)