We update the capabilities of the open-knowledge software instrument Modules for Experiments in Stellar Astrophysics (MESA). RSP is a new functionality in MESAstar that models the nonlinear radial ...stellar pulsations that characterize RR Lyrae, Cepheids, and other classes of variable stars. We significantly enhance numerical energy conservation capabilities, including during mass changes. For example, this enables calculations through the He flash that conserve energy to better than 0.001%. To improve the modeling of rotating stars in MESA, we introduce a new approach to modifying the pressure and temperature equations of stellar structure, as well as a formulation of the projection effects of gravity darkening. A new scheme for tracking convective boundaries yields reliable values of the convective core mass and allows the natural emergence of adiabatic semiconvection regions during both core hydrogen- and helium-burning phases. We quantify the parallel performance of MESA on current-generation multicore architectures and demonstrate improvements in the computational efficiency of radiative levitation. We report updates to the equation of state and nuclear reaction physics modules. We briefly discuss the current treatment of fallback in core-collapse supernova models and the thermodynamic evolution of supernova explosions. We close by discussing the new MESA Testhub software infrastructure to enhance source code development.
What exactly is spatial inequality? Why does it matter? And what should be the policy response to it? These questions have become important in recent years as the spatial dimensions of inequality ...have begun to attract considerable policy interest. In China, Russia, India, Mexico, and South Africa, as well as most other developing and transition economies, spatial and regional inequality - of economic activity, incomes, and social indicators - is on the increase. Spatial inequality is a dimension of overall inequality, but it has added significance when spatial and regional divisions align with political and ethnic tensions to undermine social and political stability. Also important in the policy debate is a perceived sense that increasing internal spatial inequality is related to greater openness of economies, and to globalization in general. Despite these important concerns, there is remarkably little systematic documentation of what has happened to spatial and regional inequality over the last twenty years. Correspondingly, there is insufficient understanding of the determinants of internal spatial inequality. This volume attempts to answer the questions posed above, drawing on data from twenty-five countries from all regions of the world. They bring together perspectives and expertise in development economics and in economic geography and form a well-researched introduction to an area of growing analytical and policy importance. Available in OSO: http://www.oxfordscholarship.com/oso/public/content/economicsfinance/0199278636/toc.html Contributors to this volume - Bettina Aten, Bureau of Economic Analysis, Washington DC, on leave from Bridgewater State College. Carlos R. Azzoni, University of Sao Paulo. Luc Christiaensen, The World Bank. Donald Davis, Columbia University and National Bureau of Economic Research. Lionel Demery, independent consultant economist, formerly with the Africa Region of the World Bank. Chris Elbers, Vrije University, Amsterdam. Javier Escobal, Group for the Analysis of Development (GRADE) in Lima. Michael F. Forster, European Centre for Social Welfare Policy and Research. Jed Friedman, The World Bank, Washington DC. Alan Heston, University of Pennsylvania. David Jesuit, Central Michigan University. Ravi Kanbur, Cornell University. Peter Lanjouw, The World Bank Development Research Group, Washington DC. Songhua Lin, Denison University. Tatiane Almeida de Menezes, University of Sao Paulo and Fundacao Instituto de Pesquisas Economicas (FIPE). Naercio Menezes-Filho, University of Sao Paulo and the Institute for Fiscal Studies. Johan Mistiaen, The World Bank Development Research Group, Washington DC. Oliver Morrissey, University of Nottingham and Overseas Development Institute (ODI), London. Berk Ozler, The World Bank Development Research Group, Washington DC. Stefano Paternostro, The World Bank Poverty Reduction Group, Washington DC. Martin Ravallion, The World Bank's Research Department. Andres Rodriguez-Pose, London School of Economics and Political Science. Javier Sanchez-Reaza, CIDE (Centro de Investigacion y Docencia Economicas), Mexico City. Kenneth R. Simler, International Food Policy Research Institute (IFPRI), Washington DC. Timothy Smeeding, Syracuse University. Dirk Willem te Velde, Overseas Development Institute, London. Maximo Torero, Group for the Analysis of Development (GRADE), Lima. Anthony Venables, London School of Economics and the Centre for Economic Policy Research. David Weinstein, Columbia University. Ruslan Yemtsov, The World Bank, Washington DC.
The concepts of formal and informal remain central to the theory and practice of development more than half a century after they were introduced into the debate. They help structure the way that ...statistical services collect data on the economies of developing countries, the development of theoretical and empirical analysis, and, most important, the formulation and implementation of policy. This volume brings together a significant new collection of studies on formality and informality in developing countries. The volume is multidisciplinary in nature, with contributions from anthropologists, economists, sociologists, and political scientists. It contains contributions from among the very best analysts in development studies. Between them the chapters argue for moving beyond the formal-informal dichotomy. Useful as it has proven to be, a more nuanced approach is needed in light of conceptual and empirical advances, and in light of the policy failures brought about by a characterization of the 'informal' as 'disorganized'. The wealth of empirical information in these studies, and in the literature more widely, can be used to develop guiding principles for intervention that are based on ground level reality. Available in OSO: http://www.oxfordscholarship.com/oso/public/content/economicsfinance//toc.html Contributors to this volume - Rajeev Ahuja, Indian Council for Research on International Economic Relations Krister Andersson, Indiana University Martha Alter Chen, Harvard University Robert K. Christensen, Indiana University Basudeb Guha-Khasnobis, UNU-WIDER Keith Hart, Goldsmiths College, University of London Ravi Kanbur, Cornell University Robert Lensink, University of Groningen Norman V. Loayza, The World Bank Mark McGillivray, UNU-WIDER M. R. Narayana, Institute for Social and Economic Change Jeffrey B. Nugent, University of Southern California Elinor Ostrom, Indiana University Ana Maria Oviedo, University of Maryland Diego Pacheco, Indiana University Sally Roever, University of California, Berkeley Amos Sawyer, Indiana University Luis Serven, The World Bank Alice Sindzingre, Centre National de la Recherche Scientifique, Paris Fredrik Soderbaum, Goteborg University Shailender Swaminathan, University of Alabama Pham Thi Thu Tra Pham, University of Groningen Liz Alden Wily, Independent Land Tenure and National Resources Management Adviser
Context. Multiple stellar populations of different ages and metallicities reside in the Galactic bulge that trace its structure and provide clues to its formation and evolution. Aims. We present the ...near-infrared observations of population II Cepheids in the Galactic bulge from VISTA Variables in the Vía Láctea (VVV) survey. The JHKs photometry together with optical data from Optical Gravitational Lensing Experiment (OGLE) survey provide an independent estimate of the distance to the Galactic centre. The old, metal-poor and low-mass population II Cepheids are also investigated as useful tracers for the structure of the Galactic bulge. Methods. We identify 340 population II Cepheids in the VVV survey Galactic bulge catalogue based on their match with the OGLE-III Catalogue. The single-epoch JH and multi-epoch Ks observations complement the accurate periods and optical (VI) mean-magnitudes from OGLE. The sample consisting of BL Herculis and W Virginis subtypes is used to derive period-luminosity relations after correcting mean-magnitudes for the extinction. Our Ks-band period-luminosity relation, Ks = −2.189(0.056) log (P)−1 + 11.187(0.032), is consistent with published work for BL Herculis and W Virginis variables in the Large Magellanic Cloud. Results. We present a combined OGLE-III and VVV catalogue with periods, classification, mean magnitudes, and extinction for 264 Galactic bulge population II Cepheids that have good-quality Ks-band light curves. The absolute magnitudes for population II Cepheids and RR Lyraes calibrated using Gaia and Hubble Space Telescope parallaxes, together with calibrated magnitudes for Large Magellanic Cloud population II Cepheids, are used to obtain a distance to the Galactic centre, R0 = 8.34 ± 0.03(stat.) ± 0.41(syst.), which changes by + 0.05-0.25 with different extinction laws. While noting the limitation of small number statistics, we find that the present sample of population II Cepheids in the Galactic bulge shows a nearly spheroidal spatial distribution, similar to metal-poor RR Lyrae variables. We do not find evidence of the inclined bar as traced by the metal-rich red-clump stars. Conclusions. Population II Cepheid and RR Lyrae variables follow similar period-luminosity relations and trace the same metal-poor old population in the Galactic bulge. The number density for population II Cepheids is more limited as compared to abundant RR Lyraes but they are bright and exhibit a wide range in period that provides a robust period-luminosity relation for an accurate estimate of the distance to the Galactic centre.
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This collection of essays provides a state-of-the-art examination of the concepts and methods that can be used to understand poverty dynamics. It does this from an interdisciplinary perspective and ...includes the work of anthropologists, economists, sociologists, and political scientists. The contributions included highlight the need to conceptualise poverty from a multidimensional perspective and promote Q-Squared research approaches, or those that combine quantitative and qualitative research. The first part of the book provides a review of the research on poverty dynamics in developing countries. Part two focuses on poverty measurement and assessment, and discusses the most recent work of world-leading poverty analysts. The third part focuses on frameworks for understanding poverty analysis that avoid measurement and instead utilise approaches based on social relations and structural analysis. There is widespread consensus that poverty analysis should focus on poverty dynamics and this book shows how this idea can practically be taken forward. Contributors to this volume - Tony Addison, Brooks World Poverty Institute, University of Manchester Jo Boyden, University of Oxford Cesar Calvo, University of Oxford Michael R. Carter, University of Wisconsin-Madison Elizabeth Cooper, University of Oxford Peter Davis, University of Bath Stefan Dercon, University of Oxford Andrew Felton, University of Maryland James E. Foster, Vanderbilt University Maia Green, University of Manchester Isabel Gunther, Harvard University John Harriss, Simon Fraser University David Hulme, University of Manchester Munenobu Ikegami, University of Wisconsin-Madison Ravi Kanbur, Cornell University Stephan Klasen, University of Gottingen Anirudh Krishna, Duke University Caroline Moser, University of Manchester S. R. Osmani, University of Ulster Agnes Quisumbing, International Food Policy Research Institute Andries du Toit, University of the Western Cape Michael Woolcock, Brooks World Poverty Institute
We present the analysis of four first overtone RR Lyrae stars observed with the Kepler space telescope, based on data obtained over nearly 2.5 yr. All four stars are found to be multiperiodic. The ...strongest secondary mode with frequency f... has an amplitude of a few mmag, 20-45 times lower than the main radial mode with frequency f... The two oscillations have a period ratio of P.../P... = 0.612-0.632 that cannot be reproduced by any two radial modes. Thus, the secondary mode is non-radial. Modes yielding similar period ratios have also recently been discovered in other variables of the RRc and RRd types. These objects form a homogenous group and constitute a new class of multimode RR Lyrae pulsators, analogous to a similar class of multimode classical Cepheids in the Magellanic Clouds. Because a secondary mode with P.../P... ~ 0.61 is found in almost every RRc and RRd star observed from space, this form of multiperiodicity must be common. In all four Kepler RRc stars studied, we find subharmonics of f... at ~1/2f... and at ~3/2f... This is a signature of period doubling of the secondary oscillation, and is the first detection of period doubling in RRc stars. The amplitudes and phases of f... and its subharmonics are variable on a time-scale of 10-200 d. The dominant radial mode also shows variations on the same time-scale, but with much smaller amplitude. In three Kepler RRc stars we detect additional periodicities, with amplitudes below 1 mmag, that must correspond to non-radial g-modes. Such modes never before have been observed in RR Lyrae variables. (ProQuest: ... denotes formulae/symbols omitted.)
We present a detailed study of the viewing angles and geometry of the inner LMC (rho ~ 4 super(j0)) based on a sample of more than 2000 MACHO Cepheids with complete {VR} sub(KC) light curves and ...single-phase Two Micron All Sky Survey (2MASS) JHK sub(s) observations. The sample is considerably larger than any previously studied subset of LMC Cepheids and has an improved areal coverage. Single-epoch random-phase 2MASS photometry is corrected using MACHO V light curves to derive mean JHK sub(s) magnitudes. We analyze the resulting period-luminosity relations in VRJHK sub(s) to recover statistical reddening and distance to each individual Cepheid, with respect to the mean distance modulus and reddening of the LMC. By fitting a plane solution to the derived individual distance moduli, the values of LMC viewing angles are obtained: position angle theta = 151 degree 0 plus or minus 2 degree 4, inclination i = 30 degree 7 plus or minus 1 degree 1. In the so-called ring analysis, we find a strong dependence of the derived viewing angles on the adopted center of the LMC, which we interpret as being due to deviations from planar geometry. Analysis of residuals from the plane fit indicates the presence of a symmetric warp in the LMC disk and the bar elevated above the disk plane. Nonplanar geometry of the inner LMC explains a broad range for values of i and theta in the literature and suggests caution when deriving viewing angles from inner LMC data.
This book brings together prominent international contributors to consider a range of questions concerning the quality of growth in Africa. Offering both diagnoses and prescriptions, The Quality of ...Growth in Africa helps envision a future that goes beyond increasing GDP to ensuring that growth translates into improvements in well-being.
Using Spitzer archival data from the SAGE (Surveying the Agents of a Galaxy's Evolution) program, we derive the Cepheid period-luminosity (P-L) relation at 3.6, 4.5, 5.8, and 8.0 mum for Large ...Magellanic Cloud (LMC) Cepheids. These P-L relations can be used, for example, in future extragalactic distance scale studies carried out with the James Webb Space Telescope. We also derive Cepheid period-color (P-C) relations in these bands and find that the slopes of the P-C relations are relatively flat. We test the nonlinearity of these P-L relations with the F- statistical test and find that the 3.6, 4.5, and 5.8 mum P-L relations are consistent with linearity. However, the 8.0 mum P-L relation presents possible but inconclusive evidence of nonlinearity.
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