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Swinburne University of Technology is an Australian public university of technology based in Melbourne, Victoria. Swinburne was founded in 1908 by the Honourable George Swinburne as the Eastern Suburbs Technical College. Its foundation campus is located in Hawthorn, a suburb of Melbourne which is located 7.5 km from the Melbourne central business district.In its first year, it enrolled 80 students in subjects including carpentry, plumbing and gas fitting. Today, Swinburne operates five campuses in two countries and has an enrolment of 60,000 students across vocational, undergraduate and postgraduate levels.In addition to its main Hawthorn campus, Swinburne has campuses in the Melbourne metropolitan area at Prahran, Wantirna and Croydon. Swinburne also has a branch campus in Sarawak, Malaysia which it has operated in partnership with the Sarawak State Government since 2000. Swinburne also have an online campus, Swinburne Online, which has been in operation since 2011. Internationally, Swinburne is ranked among the top 400 universities in the world by the Academic Ranking of World Universities and the Times Higher Education World University Rankings and in the top 500 universities in the world by the 2013 QS World University Rankings. Swinburne is a member of the prestigious Association of Southeast Asian Institutions of Higher Learning, but its membership of European Consortium of Innovative Universities was inactive since 2012. Swinburne University of Technology is a principal partner to the Victorian Division of Engineers Australia. Wikipedia.

Graham A.W.,Swinburne University of Technology
Astrophysical Journal

The popular log-linear relation between supermassive black hole mass, Mbh, and the dynamical mass of the host spheroid, Msph, is shown to require a significant correction. Core galaxies, typically with M bh ≳ 2 × 108 M⊙ and thought to be formed in dry merger events, are shown to be well described by a linear relation for which the median black hole mass is 0.36% - roughly double the old value of constancy. Of greater significance is that Mbh α M2 sph among the (non-pseudobulge) lower-mass systems: specifically, log [Mbh/M⊙] = (1.92 0.38)log [M sph/7 × 1010 M⊙] + (8.38 ± 0.17). "Classical" spheroids hosting a 106 M ⊙ black hole will have Mbh/Msph 0.025%. These new relations presented herein (1) bring consistency to the relation α Mbhσ5 and the fact that α Lσx with exponents of 5 and 2 for bright (MB ≲ -20.5 mag) and faint spheroids, respectively, (2) mimic the non-(log-linear) behavior known to exist in the Mbh-(Sérsic n) diagram, (3) necessitate the existence of a previously overlooked Mbhα L2.5 relation for Sérsic (i.e., not core-Sérsic) galaxies, and (4) resolve past conflicts (in mass prediction) with the M bh-σ relation at the low-mass end. Furthermore, the bent nature of the Mbh-Msph relation reported here for "classical" spheroids will have a host of important implications that, while not addressed in this paper, relate to (1) galaxy/black hole formation theories, (2) searches for the fundamental, rather than secondary, black hole scaling relation, (3) black hole mass predictions in other galaxies, (4) alleged pseudobulge detections, (5) estimates of the black hole mass function and mass density based on luminosity functions, (6) predictions for space-based gravitational wave detections, (7) connections with nuclear star cluster scaling relations, (8) evolutionary studies over different cosmic epochs, (9) comparisons and calibrations matching inactive black hole masses with low-mass active galactic nucleus data, and more. © 2012. The American Astronomical Society. All rights reserved. Source

We build a theoretical model to study the origin of the globular cluster metallicity bimodality in the hierarchical galaxy assembly scenario. The model is based on empirical relations such as the galaxy mass-metallicity relation [O/H]-Mstar as a function of redshift, and on the observed galaxy stellar mass function up to redshift z ∼ 4. We make use of the theoretical merger rates as a function of mass and redshift from the Millennium simulation to build galaxy merger trees. We derive a new galaxy [Fe/H]-Mstar relation as a function of redshift, and by assuming that globular clusters share the metallicity of their original parent galaxy at the time of their formation, we populate the merger tree with globular clusters. We perform a series of Monte Carlo simulations of the galaxy hierarchical assembly, and study the properties of the final globular cluster population as a function of galaxy mass, assembly and star formation history, and under different assumptions for the evolution of the galaxy mass-metallicity relation. The main results and predictions of the model are the following. (1) The hierarchical clustering scenario naturally predicts a metallicity bimodality in the galaxy globular cluster population, where the metal-rich subpopulation is composed of globular clusters formed in the galaxy main progenitor around redshift z ∼ 2, and the metal-poor subpopulation is composed of clusters accreted from satellites, and formed at redshifts z ∼ 3-4. (2) The model reproduces the observed relations by Peng et al. for the metallicities of the metal-rich and metal-poor globular cluster subpopulations as a function of galaxy mass; the positions of the metal-poor and metal-rich peaks depend exclusively on the evolution of the galaxy mass-metallicity relation and the [O/Fe], both of which can be constrained by this method. In particular, we find that the galaxy [O/Fe] evolves linearly with redshift from a value of ∼0.5 at redshift z ∼ 4 to a value of ∼0.1 at z = 0. (3) For a given galaxy mass, the relative strength of the metal-rich and metal-poor peaks depends exclusively on the galaxy assembly and star formation history, where galaxies living in denser environments and/or early-type galaxies show a larger fraction of metal-poor clusters, while galaxies with a sparse merger history and/or late-type galaxies are dominated by metal-rich clusters. (4) The globular cluster metallicity bimodality disappears for galaxy masses around and below Mstar ∼ 109 M⊙, and for redshifts z > 2. © 2013. The American Astronomical Society. All rights reserved. Source

Van Straten W.,Swinburne University of Technology
Astrophysical Journal, Supplement Series

A new method of polarimetric calibration is presented in which the instrumental response is derived from regular observations of PSR J0437-4715 based on the assumption that the mean polarized emission from this millisecond pulsar remains constant over time. The technique is applicable to any experiment in which high-fidelity polarimetry is required over long timescales; it is demonstrated by calibrating 7.2 years of high-precision timing observations of PSR J1022+1001 made at the Parkes Observatory. Application of the new technique followed by arrival time estimation using matrix template matching yields post-fit residuals with an uncertainty-weighted standard deviation of 880 ns, two times smaller than that of arrival time residuals obtained via conventional methods of calibration and arrival time estimation. The precision achieved by this experiment yields the first significant measurements of the secular variation of the projected semimajor axis, the precession of periastron, and the Shapiro delay; it also places PSR J1022+1001 among the 10 best pulsars regularly observed as part of the Parkes Pulsar Timing Array (PPTA) project. It is shown that the timing accuracy of a large fraction of the pulsars in the PPTA is currently limited by the systematic timing error due to instrumental polarization artifacts. More importantly, long-term variations of systematic error are correlated between different pulsars, which adversely affects the primary objectives of any pulsar timing array experiment. These limitations may be overcome by adopting the techniques presented in this work, which relax the demand for instrumental polarization purity and thereby have the potential to reduce the development cost of next-generation telescopes such as the Square Kilometre Array. © 2013 The American Astronomical Society. All rights reserved. Source

Graham A.W.,Swinburne University of Technology
Monthly Notices of the Royal Astronomical Society

Four new nuclear star cluster masses, M nc, plus seven upper limits, are provided for galaxies with previously determined black hole masses, M bh. Together with a sample of 64 galaxies with direct M bh measurements, 13 of which additionally now have M nc measurements rather than only upper limits, plus an additional 29 dwarf galaxies with available M nc measurements and velocity dispersions σ, an diagram is constructed. Given that major dry galaxy merger events preserve the M bh/L ratio, and given that L∝σ 5 for luminous galaxies, it is first noted that the observation M bh∝σ 5 is consistent with expectations. For the fainter elliptical galaxies it is known that L∝σ 2, and assuming a constant M nc/L ratio, the expectation that M nc∝σ 2 is in broad agreement with our new observational result that M nc∝σ 1.57 ± 0.24. This exponent is however in contrast to the value of ∼4 which has been reported previously and interpreted in terms of a regulating feedback mechanism from stellar winds. Finally, it is predicted that host galaxies fainter than M B∼-20.5 mag (i.e. those not formed in dry merger events) which follow the relation M bh∝σ 5, and are thus not 'pseudo-bulges', should not have a constant M bh/M host ratio but instead have. It is argued that the previous near-linear and relations have been biased by the sample selection of luminous galaxies, and as such should not be used to constrain the co-evolution of supermassive black holes in galaxies other than those luminous few built by major dry merger events. © 2012 The Author Monthly Notices of the Royal Astronomical Society © 2012 RAS. Source

A strongly correlated Fermi system plays a fundamental role in very different areas of physics, from neutron stars, quark-gluon plasmas, to high temperature superconductors. Despite the broad applicability, it is notoriously difficult to be understood theoretically because of the absence of a small interaction parameter. Recent achievements of ultracold trapped Fermi atoms near a Feshbach resonance have ushered in enormous changes. The unprecedented control of interaction, geometry and purity in these novel systems has led to many exciting experimental results, which are to be urgently understood at both low and finite temperatures. Here we review the latest developments of virial expansion for a strongly correlated Fermi gas and their applications on ultracold trapped Fermi atoms. We show remarkable, quantitative agreements between virial predictions and various recent experimental measurements at about the Fermi degenerate temperature. For equations of state, we discuss a practical way of determining high-order virial coefficients and use it to calculate accurately the long-sought third-order virial coefficient, which is now verified firmly in experiments at ENS and MIT. We discuss also virial expansion of a new many-body parameter-Tan's contact. We then turn to less widely discussed issues of dynamical properties. For dynamic structure factors, the virial prediction agrees well with the measurement at the Swinburne University of Technology. For single-particle spectral functions, we show that the expansion up to the second order accounts for the main feature of momentum-resolved rf-spectroscopy for a resonantly interacting Fermi gas, as recently reported by JILA. In the near future, more practical applications with virial expansion are possible, owing to the ever-growing power in computation. © 2012 Elsevier B.V. Source

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