Browsing by Title

Now showing items 1347-1366 of 7879

    • Corruption in the new public procurement regime in Nigeria 

      Ifejika, Solomon I (University of the Western Cape, 2018)
      Corruption in the public procurement system has been a major obstacle to Nigeria’s economic development and, as such, it has remained one of the prime concerns of successive governments, both military and civilian, since ...

    • Corruption in the prison context 

      Lukas, Muntingh (Civil Society Prison Reform Initiative, 2006)
      The point of departure of this paper is that, in general, corruption is a human rights issue, which is accentuated in the prison context given the nature of imprisonment. Three factors create an intrinsic risk for corruption ...

    • The COS-Halos survey: Rationale, design and a census of circumgalactic neutral hydrogen 

      Tumlinson, Jason; Thom, Christopher; Dave, Romeel; Werk, Jessica K.; Prochaska, J. Xavier; Tripp, Todd M.; Katz, Neal; Oppenheimer, Benjamin D.; Meiring, Joseph D.; Ford, Amanda Brady; O'Meara, John M.; Peeples, Molly S.; Sembach, Kenneth R.; Weinberg, David H. (IOP Publishing, 2013)
      We present the design and methods of the COS-Halos survey, a systematic investigation of the gaseous halos of 44 z = 0.15–0.35 galaxies using background QSOs observed with the Cosmic Origins Spectrograph aboard the Hubble ...

    • Cosmic evolution of star-forming galaxies to z 1.8 in the faint low-frequency radio source population 

      Ocran, E. F.; Taylor, A. R.; Vaccari, M. (Oxford University Press, 2019)
      We study the properties of star-forming galaxies selected at 610 MHz with the GMRT in a survey covering ∼1.86 deg2 down to a noise of ∼7.1 μJy beam−1. These were identified by combining multiple classification diagnostics: ...

    • The cosmic evolution of the IMF under the Jeans conjecture with implications for massive galaxies 

      Narayanan, Desika; Dave, Romeel (Oxford University Press, 2013)
      We examine the cosmic evolution of a stellar initial mass function (IMF) in galaxies that varies with the Jeans mass in the interstellar medium, paying particular attention to the K-band stellar mass-to-light ratio (M/LK) ...

    • Cosmic microwave background constraints on a physical model of reionization 

      Paul, S; Choudhury, T.R; Mukherjee, S (Oxford University Press, 2021)
      We study constraints on allowed reionization histories by comparing predictions of a physical seminumerical model with secondary temperature and polarization anisotropies of the cosmic microwave background (CMB). Our model ...

    • Cosmic sands: the origin of dusty, star-forming galaxies in the epoch of reionization 

      Davé, Romeel; Lower, Sidney; Narayanan, Desika (The astrophysical journal, 2023)
      We present the Cosmic Sands suite of cosmological zoom-in simulations based on the simba galaxy formation model in order to study the buildup of the first massive and dusty galaxies in the early universe. Residing in the ...

    • Cosmological 3D Hi Gas Map with HETDEX Lyα Emitters and eBOSS QSOs at z = 2: IGM-Galaxy/QSO Connection and a ∼ 40-Mpc Scale Giant Hii Bubble Candidate 

      Jarvis, Matt J.; Mukae, Shiro; Ouchi, Masami (IOP Publishing, 2020)
      We present cosmological (30−400 Mpc) distributions of neutral hydrogen (H i) in the intergalactic medium (IGM) traced by Lyα emitters (LAEs) and QSOs at z = 2.1–2.5, selected with the data of the ongoing Hobby–Eberly ...

    • Cosmological baryon transfer in the SIMBA simulations 

      Dave, Romeel; Borrow, Josh; Angles-Alcazar, Daniel (Oxford University Press, 2019)
      We present a framework for characterizing the large-scale movement of baryons relative to dark matter in cosmological simulations, requiring only the initial conditions and final state of the simulation. This is performed ...

    • Cosmological constraints from the power spectrum and bispectrum of 21cm intensity maps 

      Karagiannis, Dionysios; Maartens, Roy; Randrianjanahary, Liantsoa F. (IOP Publishing, 2022)
      The 21cm emission of neutral hydrogen is a potential probe of the matter distribution in the Universe after reionisation. Cosmological surveys of this line intensity will be conducted in the coming years by the SKAO and ...

    • Cosmological constraints on post-Newtonian parameters in effectively massless scalar-tensor theories of gravity 

      Rossi, Massimo; Ballardini, Mario; Braglia, Matteo (2019)
      We study the cosmological constraints on the variation of Newton’s constant and on post-Newtonian parameters for simple models of the scalar-tensor theory of gravity beyond the extended Jordan-BransDicke theory. We restrict ...

    • Cosmology from HI galaxy surveys with the SKA 

      Maartens, Roy; Abdalla, Filipe B.; Bull, Philip; Camera, Stefano; Benoit-Levy, Aurelien; Joachimi, Benjamin; Kirk, Donnacha; Klöckner, Hans-Rainer; Raccanelli, Alvise; Santos, Mario G.; Zhao, Gong-Bo (Proceedings of Science, 2014)
      The Square Kilometer Array (SKA) has the potential to produce galaxy redshift surveys which will be competitive with other state of the art cosmological experiments in the next decade. In this chapter we summarise what ...

    • Cosmology on the largest scales with the SKA 

      Camera, Stefano; Raccanelli, Alvise; Bull, Philip; Bertacca, Daniele; Chen, Xuelei; Ferreira, Pedro G.; Kunz, Martin; Maartens, Roy; Mao, Yi; Santos, Mario G.; Shapiro, Paul R.; Viel, Matteo; Xug, Yidong (Proceedings of Science, 2014)
      The study of the Universe on ultra-large scales is one of the major science cases for the Square Kilometre Array (SKA). The SKA will be able to probe a vast volume of the cosmos, thus representing a unique instrument, ...

    • Cosmology on ultralarge scales with intensity mapping of the neutral hydrogen 21 cm emission: limits on primodial non-gaussianity 

      Camera, Stefano; Santos, Mario G.; Ferreira, Pedro G.; Ferramacho, Luis (American Physical Society, 2013)
      The large-scale structure of the Universe supplies crucial information about the physical processes at play at early times. Unresolved maps of the intensity of 21 cm emission from neutral hydrogen HI at redshifts z ~ 1 − ...

    • Cosmology with a SKA HI intensity mapping survey 

      Santos, Mario G.; Bull, Philip; Alonso, David; Camera, Stefano; Ferreira, Pedro G.; Bernardi, Gianni; Maartens, Roy; Viel, Matteo; Villaescusa-Navarro, Francisco; Abdalla, Filipe B.; Jarvis, Matt; Metcalf, R. Benton; Pourtsidou, A.; Wolz, Laura (Proceedings of Science, 2014)
      HI intensity mapping (IM) is a novel technique capable of mapping the large-scale structure of the Universe in three dimensions and delivering exquisite constraints on cosmology, by using HI as a biased tracer of the ...

    • Cosmology with Phase 1 of the Square Kilometre Array Red Book 2018: Technical specifications and performance forecasts 

      Bacon, David J; Battye, Richard A.; Bull, Philip (Cambridge University Press, 2020)
      We present a detailed overview of the cosmological surveys that we aim to carry out with Phase 1 of the Square Kilometre Array (SKA1) and the science that they will enable. We highlight three main surveys: a medium-deep ...

    • Cosmology with photometrically classified type IA supernovae from the SDSS-II supernova survey 

      Campbell, Heather; D’Andrea, Chris B.; Nichol, Robert C.; Sako, Masao; Smith, Mathew (The American Astronomical Society, 2013)
      We present the cosmological analysis of 752 photometrically–classified Type Ia Supernovae (SNe Ia) obtained from the full Sloan Digital Sky Survey II (SDSS-II) Supernova (SN) Survey, supplemented with host–galaxy ...

    • COSMOS2020: A panchromatic view of the universe to z ∼ 10 from two complementary catalogs 

      Weaver, J.R; Vaccari, M.; Kauffmann, O.B. (University of the Western Cape, 2022)
      The Cosmic Evolution Survey (COSMOS) has become a cornerstone of extragalactic astronomy. Since the last public catalog in 2015, a wealth of new imaging and spectroscopic data have been collected in the COSMOS field. This ...

    • Cosmos2020: A panchromatic view of the universe to z∼10 from two complementary catalogs 

      Weaver, John R.; Kauffmann, Olivier; Vaccari, Mattia (IOP Publishing, 2022)
      The Cosmic Evolution Survey (COSMOS) has become a cornerstone of extragalactic astronomy. Since the last public catalog in 2015, a wealth of new imaging and spectroscopic data have been collected in the COSMOS field. This ...

    • Cost and cost-effectiveness of a parenting programme to prevent violence against adolescents in South Africa 

      Redfern, Alice; Cluver, Lucie D; Casale, Marisa (BMJ Publishing Group, 2019)
      This paper presents the costs and costeffectiveness of ‘Parenting for Lifelong Health: Sinovuyo Teen’, a non-commercialised parenting programme aimed at preventing violence against adolescents in low-income and middle-income ...