Electromagnetic form factors of the baryon octet in the perturbative chiral quark model

We apply the perturbative chiral quark model at one loop to analyze the electromagnetic form factors of the baryon octet. The analytic expressions for baryon form factors, which are given in terms of fundamental parameters of low-energy pion-nucleon physics (weak pion decay constant, axial nucleon coupling, strong pion-nucleon form factor), and the numerical results for baryon magnetic moments, charge and magnetic radii are presented. Our results are in good agreement with experimental data.Comment: 15 pages, 6 figures, to be published in Eur. Phys. J.

Emergence of superfluid transport in a dynamical system of ultracold atoms

The dynamics of a Bose-Einstein condensate is studied theoretically in a combined periodic plus harmonic external potential. Different dynamical regimes of stable and unstable collective dipole and Bloch oscillations are analysed in terms of a quantum mechanical pendulum model. Nonlinear interactions are shown to counteract quantum-mechanical dephasing and lead to phase-coherent, superfluid transport

Electrostatic image effects for counter-ions between charged planar walls

We study the effect of dielectric inhomogeneities on the interaction between two planparallel charged surfaces with oppositely charged mobile charges in between. The dielectric constant between the surfaces is assumed to be different from the dielectric constant of the two semiinfinite regions bounded by the surfaces, giving rise to electrostatic image interactions. We show that on the weak coupling level the image charge effects are generally small, making their mark only in the second order fluctuation term. However, in the strong coupling limit, the image effects are large and fundamental. They modify the interactions between the two surfaces in an essential way. Our calculations are particularly useful in the regime of parameters where computer simulations would be difficult and extremely time consuming due to the complicated nature of the long range image potentials.Comment: 21 pages, 8 figure

Josephson oscillation of a superfluid Fermi gas

Using the complete numerical solution of a time-dependent three-dimensional mean-field model we study the Josephson oscillation of a superfluid Fermi gas (SFG) at zero temperature formed in a combined axially-symmetric harmonic plus one-dimensional periodic optical-lattice (OL) potentials after displacing the harmonic trap along the axial OL axis. We study the dependence of Josephson frequency on the strength of the OL potential. The Josephson frequency decreases with increasing strength as found in the experiment of Cataliotti et al. [Science 293 (2001) 843] for a Bose-Einstein condensate and of the experiment of Pezze et al. [Phys. Rev. Lett. 93 (2004) 120401] for an ideal Fermi gas. We demonstrate a breakdown of Josephson oscillation in the SFG for a large displacement of the harmonic trap. These features of Josephson oscillation of a SFG can be tested experimentally.Comment: 7 pages, 10 figure

Access to undergraduate research experiences at a large research university

The American Physical Society recently released a statement calling on all university physics departments to provide or facilitate access to research experiences for all undergraduate students. In response, we investigated the current status of access to undergraduate research at University of Colorado Boulder (CU), a large research institution where the number of undergraduate physics majors outnumber faculty by roughly ten to one. We created and administered two surveys within CU's Physics Department: one probed undergraduate students' familiarity with, and participation in, research; the other probed faculty members' experiences as research mentors to undergraduates. We describe the development of these instruments, our results, and our corresponding evidence-based recommendations for improving local access to undergraduate research experiences. Reflecting on our work, we make several connections to an institutional change framework and note how other universities and colleges might adapt our process.Comment: 4 pages, 3 figures, 1 table; Submitted to 2015 PERC Proceeding

Modelling nucleon-nucleon scattering above 1 GeV

Motivated by the recent measurement of proton-proton spin-correlation parameters up to 2.5 GeV laboratory energy, we investigate models for nucleon-nucleon (NN) scattering above 1 GeV. Signatures for a gradual failure of the traditional meson model with increasing energy can be clearly identified. Since spin effects are large up to tens of GeV, perturbative QCD cannot be invoked to fix the problems. We discuss various theoretical scenarios and come to the conclusion that we do not have a clear phenomenological understanding of the spin-dependence of the NN interaction above 1 GeV.Comment: 36 pages, 8 figure

Pengaruh Motivasi Intrinsik terhadap Kinerja Guru Dimoderasi Kepemimpinan Trasformasional dan Budaya Organisasional (Studi pada Guru SD Negeri Kecamatan Doro Kabupaten Pekalongan)

This study aims to know how influence intrinsic motivation on teacher performance, how influence transformational leadhership influence on teacher performance, how influence culturerole organizational influence on teacher performance, how influence transformational leadhership moderation intrinsic motivation impact on teacher performance, and how influence culture roleorganizational moderation pedagogic competence impact on teacher performance. In this study population on Teacher in Doro Subdistrict Regency Pekalongan, while the samples used as many142 people as respondents to the random sampling proportional technique. Data were analyzed using multiple regression analysis. Results of the study can be summarized as follows intrinsicmotivation influence on teacher performance, transformational leadership not influence on teacher performance, culture role organizational significant positif influence on teacherperformance, transformational leadership not moderation intrinsic motivation impact on teacher performance, and culture role organizational not moderation intrinsic motivation impact onteacher performance

Pengaruh Kompetensi Profesional dan Motivasi Kerja terhadap Kinerja Guru Dimoderasi Kepemimpinan Kepala Sekolah

This study aimed to analyze the role of the Leadership Principal Moderating Effect of Professional Competence and Motivation for Primary Teachers performance throughout the District Talun Pekalongan. In this study population all primary school teachers in the district Talun civil servants, whereas samples taken as many as 136 people as respondents with purposive sampling technique. Measurements using a Likert scale of 5 (five) alternative answers. Test instruments used are validity and reliability. While the test model used is the coefficient of determination and F test (goodnes of Fit). Test this hypothesis using regression analysis. Based on the results of the study can be summarized as follows: (i) Professional Competence positive and significant impact on teacher performance, (ii) Work Motivation positive and significant impact on teacher performance, (iii) Leadership Principal has no effect on teacher performance, (iv) Leadership Principal does not moderate the influence of professional competence of the teacher performance, (v) Leadership Principal Work Discipline does not moderate influence on Teacher Performance

Pengaruh Percaya Diri dan Pengendalian Emosi Diri terhadap Efikasi Guru Dimoderasi Idealisasi Pengaruh di SMP Negeri Kecamatan Juwana, Kabupaten Pati

This research\u27s purpose is to find how the influence of self confident and emotional self control to the teacher\u27sefficacy moderated by Idealized influenced. The study population is a government school teachers in four JuniorHigh School in the district Juwana, Pati regency. Sampling using proportional sampling method . The number ofsamples by using the formula Slovin.. Collecting the data using questionnaires . The amount of data that can beanalyzed as many as 120. The data were analyzed using regression -based model of quasi moderator interaction.The results showed that ( 1 ) the dimensions of confidence affect the efficacy of teachers , ( 2 ) the dimensions ofemotional self- control affect the efficacy of teachers , ( 3 ) Idealized influenced influence on the efficacy of teachers, ( 4 ) Idealized influenced moderates influence of confidence on the efficacy of teachers , ( 5 ) Idealized influencedmoderates influence of emotional self- control on the efficacy of teachers