Pair formation and collapse in imbalanced Fermion populations with unequal masses

We present an exact Quantum Monte Carlo study of the effect of unequal masses on pair formation in Fermionic systems with population imbalance loaded into optical lattices. We have considered three forms of the attractive interaction and find in all cases that the system is unstable and collapses as the mass difference increases and that the ground state becomes an inhomogeneous collapsed state. We also address the question of canonical vs grand canonical ensemble and its role, if any, in stabilizing certain phases

Characterization of ultrasound fields using a potential optical flow based synthetic schlieren tomography

Synthetic schlieren tomography is an optical imaging method for characterization of ultrasound fields based on observing bending of light due to acousto-optic effect. In this work, potential optical flow based pressure estimation method is introduced

Heavy meson masses and decay constants from relativistic heavy quarks in full lattice QCD

We determine masses and decay constants of heavy-heavy and heavy-charm pseudoscalar mesons as a function of heavy quark mass using a fully relativistic formalism known as Highly Improved Staggered Quarks for the heavy quark. We are able to cover the region from the charm quark mass to the bottom quark mass using MILC ensembles with lattice spacing values from 0.15 fm down to 0.044 fm. We obtain f_{B_c} = 0.427(6) GeV; m_{B_c} = 6.285(10) GeV and f_{\eta_b} = 0.667(6) GeV. Our value for f_{\eta_b} is within a few percent of f_{\Upsilon} confirming that spin effects are surprisingly small for heavyonium decay constants. Our value for f_{B_c} is significantly lower than potential model values being used to estimate production rates at the LHC. We discuss the changing physical heavy-quark mass dependence of decay constants from heavy-heavy through heavy-charm to heavy-strange mesons. A comparison between the three different systems confirms that the B_c system behaves in some ways more like a heavy-light system than a heavy-heavy one. Finally we summarise current results on decay constants of gold-plated mesons.Comment: 16 pages, 12 figure

Verkostonalyysiä soveltamalla voidaan tutkia kuinka opettajaopiskelijat näkevät yhteydet opetttajantiedon osa-alueiden välillä

In this article we present a new approach to investigating teacher knowledge. The essay data related to Finnish future teachers' (N = 18) perceptions of the "knowledge required for teaching mathematics" were transformed into a network. We classified the knowledge topics using the Mathematical Knowledge for Teaching (MKT) framework and examined the relationships between the issues raised with the aid of network analysis. According to the results, the future teachers see the six MKT domains in a hierarchical sequence. As it is not subject specific, this approach is also applicable in the investigation of teacher knowledge of other subjects. (C) 2018 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

Teachers and their Educators - Views on Contents and their Development Needs in Mathematics Teacher Education

Finland has scored well in international assessments (e.g. PISA, TIMSS), and the pressure to attain excellent scores has activated a drive toward even more effective mathematics teacher education. This article presents the results of a qualitative assessment of the mathematics teacher education provided by the University of Eastern Finland. In this study, the views held by practicing teachers (N=101) and teacher educators (N=19) are compared so that the outstanding development needs of mathematics teacher education in terms of their contents can be revealed. The data was gathered via an electronic survey and was mainly analyzed using data-driven methods. In addition, framework provided by Mathematical Knowledge for Teaching (MKT) was used to categorize the respondents’ views regarding the contents of mathematics teacher education and to develop general guidelines for the reform of mathematics teacher education. The results indicate that mathematics teacher education should include pure mathematical content (Common Content Knowledge, CCK) and mathematical content that will have been designed only for future teachers (Specialized Content Knowledge, SCK). Teacher educators and practicing teachers both held the view that the relevance of CCK studies depend on the connections between university and school mathematics. Pedagogical studies should also be reformed because practicing teachers have realized that effective teaching (Knowledge of Content and Teaching, KCT) requires knowledge about learning mathematics (Knowledge of Content and Students, KCS) that is not offered in the current educational system on a sufficiently broad basis. In this study, suggestions for developing mathematics teacher education were mostly connected to four domains of MKT: (CCK, SCK, KCT and KCS). Interestingly those domains are the same domains which has been empirically tested and better conceptualized

Precision tests of the J/{\psi} from full lattice QCD: mass, leptonic width and radiative decay rate to {\eta}_c

We calculate the J/{\psi} mass, leptonic width and radiative decay rate to \gamma \eta_c from lattice QCD including u, d and s quarks in the sea for the first time. We use the Highly Improved Staggered Quark formalism and nonperturbatively normalised vector currents for the leptonic and radiative decay rates. Our results are: M_{J/\psi} -M_{\eta_c} = 116.5(3.2) MeV; \Gamma(J/{\psi} to e^+e^-) = 5.48(16) keV; \Gamma(J/{\psi} to \gamma \eta_c) = 2.49(19) keV. The first two are in good agreement with experiment, with \Gamma(J/{\psi} to e^+e^-) providing a test of a decay matrix element in QCD, independent of CKM uncertainties, to 2%. At the same time results for the time moments of the correlation function can be compared to values from the charm contribution to \Gamma(e^+e^- to hadrons), giving a 1.5% test of QCD. Our results show that an improved experimental error would enable a similarly strong test from \Gamma(J/{\psi} to \gamma \eta_c).Comment: 20 pages, 16 figures. Added some text plus a figure and two tables comparing the time moments of the charmonium vector correlator to results extracted from experiment for the charm contribution to e^+e^- -> hadrons. This allows a 1.5% test of QCD. Further minor amendments to the text. Version accepted for publication by Physical Review

Sixfold Post-Fracture Mortality in 16-To 30-Year-Old Patients-Suicides, Homicides, and Intoxications Among Leading Causes of Death

Background and Aims: The death of any young individual is associated with the loss of many potentially fulfilling years of life. It has been suggested that the relative mortality of fracture patients may be higher in younger age groups than in older cohorts. We determined the mortality and causes of death in a cohort of 16- to 30-year-old patients that had been hospitalized for fractures. Material and Methods: We collected data using criteria based on the diagnosis code (International Statistical Classification of Diseases and Related Health Problems, 10th Revision), surgical procedure code (Nordic Medico-Statistical Committee), and seven additional characteristics of patients admitted to the trauma ward at the Central Finland Hospital between 2002 and 2008. Patients were then followed to ascertain their mortality status until the end of 2012. Standardized mortality ratios were calculated and causes of death were determined by combining our registry data with data provided by Statistics Finland. Results: During the study, 199 women and 525 men aged 16-30 years had sustained fractures. None of these patients died during the primary hospital stay. At the end of follow-up (mean duration 7.4 years), 6 women and 23 men had died. The standardized mortality ratio for all patients was 6.2 (95% Confidence Interval: 4.3-8.9). Suicides and intoxications comprised over half, and motor vehicle accidents and homicides comprised nearly a third of the post-fracture deaths. Conclusion: We found a concerning increase in mortality among young adults that had been hospitalized due to a fracture compared to the general population that had been standardized by age, sex, and calendar-period. Leading causes of death were suicides and intoxications or motor vehicle accidents and homicides, which may be indicative of depressive disorders or impulse control disorders, respectively. Identification of the underlying psychosocial problems may provide an opportunity for preventive interventions.Peer reviewe