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Black Holes 'NSinc: The SA discovery that’s got astronomers in a spin

A deep scan of the sky in radio waves revealed something completely unexpected to South African astronomers: that somehow, and for some unexplained reason, supermassive black holes in one region of space are all releasing radio waves in the same direction. Could this be a vital clue in understanding how the universe was formed?

Astronomers Perplexed By Rare Alignment Of Supermassive Black Holes (Youtube video)

Centre For RadioCosmology: Astronomy For The 21st Century

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  • The observed galaxy bispectrum from single-field inflation in the squeezed limit 

    Koyama, Kazuya; Umeh, Obinna; Maartens, Roy; Bertacca, Daniele (IOP Publishing, 2018)
    Using the consistency relation in Fourier space, we derive the observed galaxy bispectrum from single- eld in ation in the squeezed limit, in which one of the three modes has a wavelength much longer than the other two. ...
  • The Galactic halo pulsar population 

    Rajwade, Kaustubh; Chennamangalam, Jayanth; Lorimer, Duncan R.; Karastergiou, Aris (Oxford University Press, 2018)
    Most population studies of pulsars have hitherto focused on the disc of the Galaxy, the Galactic centre, globular clusters, and nearby galaxies. It is expected that pulsars, by virtue of their natal kicks, are also to ...
  • Predicting the neutral hydrogen content of galaxies from optical data using machine learning 

    Rafieferantsoa, Mika; Andrianomena, Sambatra; Dave, Romeel (Oxford University Press, 2018)
    We develop a machine learning-based framework to predict the Hi content of galaxies using more straightforwardly observable quantities such as optical photometry and environmental parameters. We train the algorithm on z ...
  • Synergies between intensity maps of hydrogen lines 

    Fonseca, Jose; Maartens, Roy; Santos, Mario G. (Oxford University Press, 2018)
    We study synergies between Hi 21cm and Hα intensity map observations, focusing on SKA1- like and SPHEREx-like surveys. We forecast how well such a combination can measure features in the angular power spectrum on the ...
  • Aligned metal absorbers and the ultraviolet background at the end of reionization 

    Doughty, Caitlin; Finlator, Kristian; Oppenheimer, Benjamin D.; Dave, Romeel; Zackrisson, Erik (Oxford University Press, 2018)
    We use observations of spatially-aligned C ii, C iv, Si ii, Si iv, and O i absorbers to probe the slope and intensity of the ultraviolet background (UVB) at z ∼ 6. We accom- plish this by comparing observations with ...
  • News from the EREBOS project 

    Schaffenroth, Veronika; Barlow, Brad; Geier, Stephan; Vučković, Maja; Kilkenny, Dave; Schaffenroth, Johannes (De Gruyter Open, 2017)
    Planets and brown dwarfs in close orbits will interact with their host stars, as soon as the stars evolve to become red giants. However, the outcome of those interactions is still unclear. Recently, several brown dwarfs ...
  • Forming the Moon from terrestrial silicate-rich material 

    de Meijer, R.J.; Anisichkin, V.F.; van Westrenen, W. (Elsevier, 2013)
    Recent high-precision measurements of the isotopic composition of lunar rocks demonstrate that the bulk silicate Earth and the Moon show an unexpectedly high degree of similarity. This is inconsistent with one of the ...
  • Visible and IR photoluminescence of c-FeSi@a–Si core–shell nano-fibres produced by vapour transport 

    Thabethe, Sibongiseni; Linganiso, Ella; Motaung, David; Mashapa, Matete G.; Nkosi, Steven; Arendse, Christopher; Mwakikung, Bonex W. (Elsevier, 2013)
    The procedures for the synthesis of amorphous ε-FeSi/Sicore–shell nanofibres by vapour transport in a CVD configuration are reported. Crystallite studies by the Williamson-Hall method show the sizes to be typically about ...
  • Characterization of silicon nitride thin films deposited by hot-wire CVD at low gas flow rates 

    Oliphant, Clive J.; Arendse, Christopher; Muller, Theophillus F.G.; Knoesen, Dirk (Elsevier, 2013)
    We examined the chemical, structural, mechanical and optical properties of amorphous hydrogenatedsilicon nitride thin films deposited by hot-wire chemical vapour deposition using SiH4, NH3and H2gases at total flow rates ...
  • A comparison of Einstein-Boltzmann solvers for testing General Relativity 

    Bellini, Emilio; Barreira, A.; Frusciante, N.; Ballardini, M. (American Physical Society, 2018)
    We compare Einstein-Boltzmann solvers that include modifications to General Relativity and find that, for a wide range of models and parameters, they agree to a high level of precision. We look at three general purpose codes ...
  • Octupole correlations in the structure of O2 bands in the N=88 nuclei150Sm Gd 

    Bvumbi, S.P.; Sharpey-Schafer, J.F.; Jones, P.M.; Mullins, S.M. (American Physical Society, 2013)
    Knowledge of the exact microscopic structure of the 01 + ground state and first excited 02 + state in 150Sm is required to understand the branching of double β decay to these states from 150Nd. The detailed spectroscopy ...
  • The kinematic dipole in galaxy redshift surveys 

    Maartens, Roy; Clarkson, Chris; Chen, Song (IOP Publishing, 2018)
    In the concordance model of the Universe, the matter distribution { as observed in galaxy number counts or the intensity of line emission (such as the 21cm line of neutral hydrogen) - should have a kinematic dipole due ...
  • VLT/XSHOOTER & Subaru/MOIRCS spectroscopy of HUDF-YD3: No evidence for Lyman-alpha emission at z=8.55 

    Bunker, Andrew J.; Caruana, Joseph; Wilkins, Stephen M.; Jarvis, Matt (Oxford University Press, 2013)
    We present spectroscopic observations with VLT/XSHOOTER and Subaru/MOIRCS of a relatively bright Y -band drop-out galaxy in the Hubble Ultra Deep Field, first selected by Bunker et al. (2010), McLure et al. (2010) and ...
  • Physical properties of spectroscopically-confirmed galaxies at z >= 6. II. Morphology of the rest-frame UV continuum and Lyman-alpha emission 

    Jiang, Linhua; Egami, Eiichi; Fan, Xiaohui; Dave, Romeel (IOP Science, 2013)
    We present a detailed structural and morphological study of a large sample of spectroscopicallyconfirmed galaxies at z ≥ 6, using deep HST near-IR broad-band images and Subaru optical narrowband images. The galaxy sample ...
  • Matter bispectrum in cubic Galileon cosmologies 

    Bartolo, Nicola; Bellini, Emilio; Bertacca, Daniele; Matarrese, Sabino (IOP Science, 2013)
    In this paper we obtain the bispectrum of dark matter density perturbations in the frame of covariant cubic Galileon theories. This result is obtained by means of a semi- analytic approach to second-order perturbations ...
  • Radio continuum surveys with square kilometre array pathfinders 

    Norris, Ray P.; Afonso, J.; Bacon, David; Cress, Catherine (Cambridge University Press, 2013)
    In the lead-up to the Square Kilometre Array (SKA) project, several next-generation radio telescopes and upgrades are already being built around the world. These include APERTIF (The Netherlands), ASKAP (Australia), ...
  • H2O emission in high-z ultra-luminous infrared galaxies 

    Omont, A.; Yang, Chentao; Cox, P.; Jarvis, Matt (edp sciences, 2013)
    Using the IRAM Plateau de Bure interferometer (PdBI), we report the detection of water vapor in six new lensed ultraluminous starburst galaxies at high redshift, discovered in the Herschel Astrophysical Terahertz Large ...
  • H-Atlas: The cosmic abundance of dust from the far-infrared background power spectrum 

    Thacker, Cameron; Cooray, Asantha; Jarvis, Matt (IOP Science, 2013)
    We present a measurement of the angular power spectrum of the cosmic far-infrared background (CFIRB) anisotropies in one of the extragalactic fields of the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) at ...
  • Gama/H-Atlas: The dust opacity-stellar mass surface density relation for spiral galaxies 

    Grootes, M.W.; Tuffs, R.J.; Jarvis, Matt (IOP Science, 2013)
    We report the discovery of a well-defined correlation between B-band face-on central optical depth due to dust and the stellar mass surface density of nearby spiral galaxies. This relation was derived from a sample of ...
  • Galaxy correlations and the BAO in a void universe: structure formation as a test of the Copernican Principle 

    February, Sean; Clarkson, Chris; Maartens, Roy (IOP Science, 2013)
    A suggested solution to the dark energy problem is the void model, where accelerated expansion is replaced by Hubble-scale inhomogeneity. In these models, density perturbations grow on a radially inhomogeneous background. ...

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