Browsing by Author "Brown, M"

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    A new macromedusa from the coast of Mozambique: Aurelia mozambica sp. nov. (Scyphozoa: Ulmaridae)
    (Magnolia Press, 2021) Brown, M; Scorrano, S; Kuplik, Z
    A new species of the cosmopolitan jellyfish genus Aurelia is described from the coastal waters of Mozambique using a combination of morphological, meristic and genetic information (COI and 18S). The species can be separated from congeners that have been recently described by a combination of bell shape, number of canal origins and anastomoses, and the shape of the manubrium and oral arms. Three types of nematocysts are present in the tissues of both the bell margin and oral arms, and this description of the cnidome will allow for future comparison. Pairwise genetic comparisons showed a mean COI divergence of 4.8% within the group, and a mean divergence ranging between 15% and 22% with all other species of Aurelia.
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    A systematic survey for z < 0.04 CLAGNs
    (Royal Astronomical Society, 2021) Senarath, M; Brown, M; Cluver, M
    We have conducted a systematic survey for z < 0.04 active Galactic nuclei (AGNs) that may have changed spectral class over the past decade. We use SkyMapper, Pan-STARRS and the V´eron-Cetty & V´eron catalogue to search the entire sky for these ‘changing-look’ AGNs (CLAGNs) using a variety of selection methods, where Pan-STARRS has a coverage of 3π steradians (sky north of Declination −30◦) and SkyMapper has coverage of ∼21000 deg2 (sky south of Declination 0◦). We use small aperture photometry to measure how colour and flux have changed over time, where a change may indicate a change in spectral type. Optical colour and flux are used as a proxy for changing Hα equivalent width, while WISE 3.4 μm flux is used to look for changes in the hot dust component. We have identified four AGNs with varying spectra selected using our optical colour selection method. Three AGNs were confirmed from recent observations with WiFeS on the 2.3 m telescope at Siding Spring and the other was identified from archival spectra alone. From this, we identify two new CLAGNs; NGC 1346 and 2MASX J20075129–1108346.We also recover Mrk 915 and Mrk 609, which are known to have varying spectra in the literature, but they do not meet our specific criteria for CLAGNs.