Faculty of Natural Sciences: Recent submissions
Now showing items 1901-1920 of 2659
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Gama/H-Atlas: The dust opacity-stellar mass surface density relation for spiral galaxies
(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
(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. ... -
Galaxy And Mass Assembly (GAMA): Resolving the role of environment in galaxy evolution
(Oxford University Press, 2013)We present observations of 18 galaxies from the Galaxy And Mass Assembly (GAMA) survey made with the SPIRAL optical integral field unit (IFU) on the Anglo- Australian Telescope. The galaxies are selected to ... -
Galaxy And Mass Assembly (GAMA): spectroscopic analysis
(Oxford University Press, 2013)The Galaxy And Mass Assembly (GAMA) survey is a multiwavelength photometric and spectroscopic survey, using the AAOmega spectrograph on the Anglo-Australian Telescope to obtain spectra for up to _ 300 000 galaxies over ... -
Balancing redox cofactor generation and ATP synthesis: key microaerobic responses in thermophilic fermentations
(Wiley, 2013)Geobacillus thermoglucosidasius is a Grampositive, thermophilic bacterium capable of ethanologenic fermentation of both C5 and C6 sugars and may have possible use for commercial bioethanol production [Tang et al., 2009; ... -
Improving photometric redshift estimation using GPz: size information, post processing and improved photometry
(Oxford University Press, 2017)The next generation of large-scale imaging surveys (such as those conducted with the Large Synoptic Survey Telescope and Euclid) will require accurate photometric redshifts in order to optimally extract cosmological ... -
Factors affecting the enrolment rate of students in Higher Education Institutions in the Gauteng province, South Africa
(SAGE, 2018)The purpose of this research is to investigate and analyse higher education institutions' enrolment and drop-out rates within the Gauteng province, South Africa. Large-scale secondary data from the General Household ... -
MUFASA: The strength and evolution of galaxy conformity in various tracers
(Oxford University Press, 2017)We investigate galaxy conformity using the Mufasa cosmological hydrodynamical simulation. We show a bimodal distribution in galaxy colour with radius, albeit with too many low-mass quenched satellite galaxies compared ... -
Galaxy and mass assembly: evolution of the Hα luminosity function and star formation rate density up to z < 0.35
(OUP, 2013)Measurements of the low-z Hα luminosity function, Φ, have a large dispersion in the local number density of sources (∼0.5–1 Mpc−3 dex−1), and correspondingly in the star formation rate density (SFRD). The possible causes ... -
Extending BEAMS to incorporate correlated systematic uncertainties
(IOP Science, 2013)New supernova surveys such as the Dark Energy Survey, Pan-STARRS and the LSST will produce an unprecedented number of photometric supernova candidates, most with no spectroscopic data. Avoiding biases in cosmological ... -
Assessment of temporal and spatial evolution of bacterial communities in a biological sand filter mesocosm treating winery wastewater
(The Society for Applied Microbiology, 2013)AIMS: To assess the impact of winery wastewater (WW) on biological sand filter (BSF) bacterial community structures, and to evaluate whether BSFs can constitute alternative and valuable treatment-processes to remediate WW. ... -
Evolution of faint radio sources in the VIDEO-XMM3 field
(OUP, 2013)It has been speculated that low luminosity radio-loud AGN have the potential to serve as an important source of AGN feedback, and may be responsible for suppressing star-formation activity in massive elliptical galaxies ... -
Cosmology with photometrically classified type IA supernovae from the SDSS-II supernova survey
(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 ... -
EC 10246-2707: a new eclipsing sdB + M dwarf binary⋆
(OUP, 2013)We announce the discovery of a new eclipsing hot subdwarf B + M dwarf binary, EC 10246-2707, and present multi-colour photometric and spectroscopic observations of this system. Similar to other HW Vir-type binaries, the ... -
Evolution of star formation in the UKIDSS ultra deep survey field - I. Luminosity functions and cosmic star formation rate out of z = 1.6
(OUP, 2013)We present new results on the cosmic star formation history in the SXDS-UDS field out to z = 1.6. We compile narrow-band data from the Subaru Telescope and the Visible and Infrared Survey Telescope for Astronomy (VISTA) ... -
Constraining the bright-end of the UV luminosity function for z ~ 7-9 galaxies: results from CANDELS/GOODS-South
(OUP, 2013)The recent Hubble Space Telescope near-infrared imaging with the Wide-Field Camera #3 (WFC3) of the GOODS-South field in the CANDELS program covering nearly 100 arcmin2, along with already existing Advanced Camera for ... -
Cosmology on ultralarge scales with intensity mapping of the neutral hydrogen 21 cm emission: limits on primodial non-gaussianity
(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 − ... -
Comparison of Hi and optical redshifts of galaxies - The impact of redshift uncertainties on spectral line stacking
(Oxford University Press, 2013)Accurate optical redshifts will be critical for spectral co-adding techniques used to extract detections from below the noise level in ongoing and upcoming surveys for Hi, which will extend our current understanding of ... -
Synthesis and biological evaluations of NO-donating oxa- and aza-pentacycloundecane derivatives as potential neuroprotective candidates
(MDPI, 2018)In order to utilize the neuroprotective properties of polycyclic cage compounds, and explore the NO-donating ability of nitrophenyl groups, an array of compounds was synthesized where the different nitrophenyl groups ... -
Constraints on anisotropic cosmic expansion from supernovae
(Edp Sciences, 2013)AIMS. We test the isotropy of the expansion of the Universe by estimating the hemispherical anisotropy of supernova type Ia (SN Ia) Hubble diagrams at low redshifts (z < 0.2). METHODS. We compare the best fit Hubble ...