Now showing items 1-20 of 56

  • High-Precision Branching Ratio Measurement for the Superallowed + Emitter 74Rb 

    Dunlop, R.; Ball, G.C.; Leslie, J.R.; Svensson, C.E.; Towner, I.S.; Andreoiu, C.; Chagnon-Lessard, S.; Chester, A.; Cross, D.S.; Finlay, P.; Garnsworthy, A.B.; Garrett, P.E.; Glister, J.; Hackman, G.; Hadinia, B.; Leach, K. G.; Rand, E.T.; Starosta, K.; Tardiff, E.R.; Triambak, S.; Williams, S. J.; Wong, J.; Yates, S.W.; Zganjar, E.F. (American Physical Society, 2013)
    A high-precision branching-ratio measurement for the superallowed β + decay of 74Rb was performed at the TRIUMF Isotope Separator and Accelerator (ISAC) radioactive ion-beam facility. The scintillating electronpositron tagging ...
  • Isothermal dust models of Herschel-ATLAS galaxies 

    Smith, D.J.B.; Hardcastle, M.J.; Jarvis, Matt (Oxford University Press, 2013)
    We use galaxies from the Herschel-ATLAS survey, and a suite of ancillary simulations based on an isothermal dust model, to study our ability to determine the effective dust temperature, luminosity and emissivity index of ...
  • Herschel-ATLAS/GAMA: What determines the far-infrared properties of radio galaxies? 

    Virdee, J.S.; Hardcastle, M.J.; Jarvis, Matt (OUP, 2013)
    We perform a stacking analysis of Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) data in order to obtain isothermal dust temperatures and rest-frame luminosities at 250 µm (L250), for a well-defined sample ...
  • Herschel-atlas/Gama: a difference between star formation rates in strong-line and weak-line radio galaxies 

    Hardcastle, M.J.; Ching, J.H.Y.; Jarvis, Matt (OUP, 2013)
    We have constructed a sample of radio-loud objects with optical spectroscopy from the Galaxy and Mass Assembly (GAMA) project over the Herschel Astrophysical Terahertz Large Area Survey (Herschel-ATLAS) Phase 1 fields. ...
  • Existence domains of dust-acoustic solitons and supersolitons 

    Maharaj, S. K.; Bharuthram, Ramashwar; Singh, S. V.; Lakhina, G. S. (AIP PublishingAIP Publishing, 2013)
    Using the Sagdeev potential method, the existence of large amplitude dust-acoustic solitons and supersolitons is investigated in a plasma comprising cold negative dust, adiabatic positive dust, Boltzmann electrons, and ...
  • Black hole - galaxy correlations without self-regulation 

    Angles-Alcazar, Daniel; Ozel, Feryal; Dave, Romeel (American Astronomical Society, 2013)
    Recent models of black hole growth in a cosmological context have forwarded a paradigm in which the growth is self-regulated by feedback from the black hole itself. Here we use cosmological zoom simulations of galaxy formation ...
  • A deep search for faint galaxies associated with very low-redshift C iv absorbers: A case with cold-accretion characteristics 

    Burchett, Joseph N.; Tripp, Todd M.; Werk, Jessica K.; Howk, J. Christopher; Dave, Romeel; Prochaska, J. Xavier; Ford, Amanda Brady (The American Astronomical Society, 2013)
    Studies of QSO absorber–galaxy connections are often hindered by inadequate information on whether faint/dwarf galaxies are located near the QSO sight lines. To investigate the contribution of faint galaxies to QSO ...
  • Hot subdwarf stars in close-up view IV. Helium abundances and the 3He isotopic anomaly of subdwarf B stars 

    Geier, S.; Edelmann, H.; Kilkenny, David; O'Donoghue, D.; Marsh, T.R.; Copperwheat, C. (EDP Sciences, 2013)
    Atmospheric parameters and helium abundances of 44 bright subdwarf B stars have been determined. More than half of our sample consists of newly discovered stars from the Edinburgh Cape survey. We showed that effective ...
  • Self-catalytic growth of tin oxide nanowires by chemical vapor deposition process 

    Thabethe, Bongani; Malgas, Gerald; Motaung, David; Malwela, Thomas; Arendse, Christopher (Hindawi, 2013)
    We report on the synthesis of tin oxide (SnO2) nanowires by a chemical vapor deposition (CVD) process. Commercially bought SnO nanopowders were vaporized at 1050∘C for 30 minutes with argon gas continuously passing through ...
  • Theoretical evolution of optical strong lines across cosmic time 

    Kewley, Lisa J.; Dopita, Michael A.; Dave, Romeel; Leitherer, Claus; Yuan, Tiantian; Allen, Mark; Groves, Brent; Sutherland, Ralph (The American Astronomical Society, 2013)
    We use the chemical evolution predictions of cosmological hydrodynamic simulations with our latest theoretical stellar population synthesis, photoionization, and shock models to predict the strong line evolution of ...
  • Students' ontological security and agency in science education - an example from reasoning about the use of gene technology 

    Lindahl, Mats Gunnar; Linder, Cedric (Taylor & Francis, 2013)
    This paper reports on a study of how students' reasoning about socioscientific issues is framed by three dynamics: societal structures, agency and how trust and security issues are handled. Examples from gene technology ...
  • The roles of star formation and AGN activity of IRS sources in the HerMES fields 

    Feltre, Anna; Hatziminaoglou, Evanthia; Vaccari, Mattia; Hernán-Caballero, Antonio; Fritz, Jacopo; Franceschini, Alberto; Bock, Jamie; Cooray, Asantha; Farrah, Duncan; Gonzalez-Solares, Eduardo A.; Ibar, Edo; Isaak, Kate G.; Lo Faro, Barbara; Marchetti, Lucia; Oliver, Seb J.; Page, Matthew J.; Rigopoulou, Dimitra; Roseboom, Isaac G.; Symeonidis, Myrto (Oxford University Press, 2013)
    In this work we explore the impact of the presence of an active galactic nucleus (AGN) on the mid- and far-infrared (IR) properties of galaxies as well as the effects of simultaneous AGN and starburst activity in these ...
  • Using a disciplinary discourse lens to explore how representations afford meaning making in a typical wave physics course 

    Enghag, Margareta; Forsman, Jonas; Linder, Cedric; MacKinnon, Allan; Moons, Ellen (Springer Verlag, 2013)
    We carried out a case study in a wave physics course at a Swedish university in order to investigate the relations between the representations used in the lessons and the experience of meaning making in interview–discussions. ...
  • Mind the gap: Science and engineering education at the secondary–tertiary interface 

    Case, Jenni; Marshall, Delia; Grayson, Diane (Academy of Science of South Africa, 2013)
    In the South African higher education sector, there is increasing concern about the poor retention and throughput rates of undergraduate students. There is also concern that the participation rates in higher education, ...
  • The neutral hydrogen content of galaxies in cosmological hydrodynamic simulations 

    Dave, Romeel; Katz, Neal; Oppernheimer, Benjamin D.; Kollmeier, Juna A.; Weinberg, David H. (Oxford University Press, 2013)
    We examine the global HI properties of galaxies in quarter billion particle cosmological simulations using GADGET-2, focusing on howgalactic outflows impactHI content.We consider four outflow models, including a new one ...
  • The host haloes of O I absorbers in the reionization epoch 

    Finlator, Kristian; Muñoz, Joseph A.; Dave, Romeel; Oppenheimer, B. D.; Peng Oh, S.; Özel, Feryal (Oxford University Press, 2013)
    We use a radiation hydrodynamic simulation of the hydrogen reionization epoch to study OI absorbers at z ∼ 6. The intergalactic medium (IGM) is reionized before it is enriched; hence, OI absorption originates within dark ...
  • The high-ion content and kinematics of low-redshift lyman limit systems 

    Fox, Andrew J.; Lehner, Nicholas; Dave, Romeel; Tumlinson, Jason; Howk, J. Christopher; Tripp, Todd M.; Prochaska, J. Xavier; O'Meara, John M.; Werk, Jessica K.; Bordoloi, Rongmon; Katz, Neal; Oppenheimer, Benjamin D. (The American Astronomical Society, 2013)
    We study the high-ion content and kinematics of the circumgalactic medium around low-redshift galaxies using a sample of 23 Lyman limit systems (LLSs) at 0.08 < z < 0.93 observed with the Cosmic Origins Spectrograph on ...
  • 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 ...
  • Testing homegeneity with Galaxy Star formation histories 

    Hoyle, Ben; Jimenez, Raul; Maartens, Roy; Heavens, Alan; Clarkson, Chris; Tojeiro, Rita (IOP Publishing, 2013)
    Observationally confirming spatial homogeneity on sufficiently large cosmological scales is of importance to test one of the underpinning assumptions of cosmology, and is also imperative for correctly interpreting dark ...
  • 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) ...