The final paper from Shanti Krishnan’s extraordinary PhD! This work is focused on a general purpose slow control system to remotely monitor experiments with a range of sensors, in a cost-effective but still entirely reconfigurable setup that scales as your experiment does. Amazing work and one that will support others in their research efforts we hope, as the designs are all provided for further use!
Read More
Just received news from the Swinburne University of Technology promotions panel - I am now a full PROFESSOR!
Particularly pleasing in this (and the reason I want to ask your indulgence in this scandalous self-promotion) is that the promotion committee considered the entire range of my research, teaching and engagement. Swinburne truly is a place that has supported my full range of activities and values the research papers I write just as much as the science discoveries I explain to the community.
Read More
I’m CI of the dark matter detector SABRE at the Stawell Underground Physics Laboratory and can proudly announce that we've been funded by the ARC! Australia will now join an international search for the nature of dark matter as the first site in the Southern Hemisphere.
Read More
My student's third paper of a stunning 3-part series on the growth of dark matter structures. In this paper Camila finally demonstrated the long studied concentration of dark matter haloes was tied to the growth history of that halo and hence, through her other works, the basic cosmology of the universe. Reference: Correa, Wyithe, Schaye and Duffy 2015 MNRAS 452, 1217C
Read More
My student's second paper of a stunning 3-part series on the growth of dark matter structures. In this paper Camila tied the distribution of dark matter in haloes (i.e. the density profile) and initial power spectrum of the universe. This used detailed N-body simulations that Camila herself ran several of on supercomputer. Reference: Correa, Wyithe, Schaye and Duffy 2015 MNRAS 450, 1521C
Read More
My student's first paper of her PhD was a stunning 3-part series on the growth of dark matter structures. In this paper Camila set up the analytic machinery that tied the mass accretion history of haloes to the underlying cosmology of the universe using linear structure formation theory. In particular she showed that the rapid exponential growth of haloes in the early universe slows to become a slower power law at late times thanks to Dark Energy. Reference: Correa, Wyithe, Schaye and Duffy 2015 MNRAS 450, 1514-1520
Read More
With the excitement of our funding secured to build the world's first dark matter detector in the Southern Hemisphere in Stawell, Victoria we hosted VIPs and a film crew from 7's Sunrise Weekend. It was 30+ degrees and 100% humidity a km underground but that's where you need to go to search for dark matter!
Read More
The first paper from the "DRAGONS" team led by Prof Stuart Wyithe, investigating how the First Galaxies formed. Using a series of hydrodynamical simulations series known as Smaug we show that the first billion years after the Big Bang is a very exciting time, with the entire universe lit by a hidden population of small galaxies that current telescopes have yet to see. Reference: Duffy, Wyithe, Mutch, Poole 2014 MNRAS 443, 3435D.
Read More
In this paper, I analysed the ability of radio and optical (visible light) telescopes to probe the nature of Dark Energy. I showed that radio telescopes are rapidly improving in capability and although starting from a low base they will rival the best optical telescopes by the time of the Square Kilometre Array (SKA). One issue is that the SKA demands such a large supercomputer that Moore's law might not get us such a machine by the time SKA is built. Reference: Duffy 2014 Annalen der Physik 526, 283D for the Special Issue "The Accelerating Universe".
Read More
In this paper, we present a fascinating technique using the outbursts of supermassive blackholes as barometers to measure the pressure of the gas around the galaxies, as the outbursts inflate 'bubbles' of ionised gas. These pressures were then compared with the hydrodynamical simulations and found to be significantly rarer, over-pressurised regions than normal. Reference: Malarecki, Staveley-Smith, Saripalli, Subrahmanyan, Jones, Duffy, Rioja 2013 MNRAS 432 200M.
Read More
In this paper, Sarah and I started investigating the shape and spin properties of Dark Matter haloes just after I left Jodrell Bank. This then increased in scope when she started to consider the actions of the baryons (as featured in Duffy et al 2010) in changing these key properties of the collapsed Dark Matter structures. This work showed that the baryons strongly influence the halo, making it more spherical and rotating faster than the Dark Matter only predictions. This is a key result for Gravitational lensing and X-ray temperature mass estimates. Reference: Bryan, Kay, Duffy, Schaye, Dalla Vecchia, Booth 2013 MNRAS 429 3316B.
Read More
In this paper, we used one of the largest simulated universes in existence (the Millennium Simulation) we populated the Dark Matter haloes with detailed Neutral Hydrogen gas (which radio telescopes can detect). By 'observing' these objects with the expected performance of the Australian SKA Pathfinder telescope we created a series virtual surveys that ASKAP can be expected to detect. These catalogues are as detailed and real as we can hope to have until we turn the telescope on. Some incredible fly through movies and images are available (be warned they can be pretty large). Reference: Duffy, Meyer, Staveley-Smith et al 2012 MNRAS 426 3385D
Read More
This paper is our analysis of the ability of the forthcoming Australian Square Kilometre Array Pathfinder to investigate the nature of Dark Energy. It will likely be the first radio telescope to make these kind of observations and is an exciting precursor to the type of science that the full Square Kilometre Array (SKA) can accomplish. Reference: Duffy, Moss, Staveley-Smith 2012 PASA 29 202D
Read More
This new high resolution study of neutral hydrogen (HI) in local galaxies, led by Baerbel Koribalska has a great name LVHIS (almost pronounced Elvis... which is reason enough to look at this work). It's also a fantastically thorough and exhaustive study into the kinematic properties of 12 nearby dwarf galaxies. The study of galaxy rotations using the HI line isn't anything new of course, but the dataset presented here represents the quality of data that we can routinely expect from the forthcoming Australian Square Kilometre Array Pathfinder (ASKAP) and hence is a valuable guide into the uses (and pitfalls) of high resolution kinematic data.
Read More
This is a summary of 3 papers released today by the above authors (who all shuffle in order dependent on the exact paper) but basically it's a way to improve the measurements of the Baryonic Acoustic Oscillation (BAO) using the Sloan Digital Sky Survey Data Release 7 sample of galaxies... So of course the first question is, what's the BAO?
Read More
The latest 'citizen science' project to hit the astronomical shelves is a really fun investigation into the HII (ionised hydrogen) bubbles that form around young, ionising stars or Supernovae explosions. The issue here is that they can be very complex shapes as the shock wave around such ionising sources will typically flow around dense interstellar gas. This means that identifying such objects will be difficult for automated systems but easy for humans with our pretty impressive pattern recognition skills. This is the idea of the project - harness the power of people for a problem that we can uniquely solve.
Read More
Following on from Duffy et al. (2010), in this paper we considered the same simulated haloes when "Modelling neutral hydrogen in galaxies using cosmological hydrodynamical simulations". This studied the baryonic properties of simulated haloes; focussing on Neutral Hydrogen, but also Molecular Hydrogen and Stellar masses as a function of cosmic time, halo mass and baryonic physics. With this paper I made the Victorian State Finals for the Fresh Science Award. Reference: Duffy, Kay, Battye, Booth, Dalla Vecchia, Schaye 2012 MNRAS 420 2799
Read More
My first SPH simulation paper on the "Impact of baryon physics on dark matter structures: a detailed simulation study of halo density profiles". It demonstrated that the physics of galaxy formation can (surprisingly) strongly affect the dark matter distribution. It won the "Best Paper by a UWA Early Career Researcher" award. Reference: Duffy, Schaye, Kay, Dalla Vecchia, Battye, Booth 2010 MNRAS 405 2161D
Read More
This was the main simulation paper for the OverWhelmingly Large Simulations (OWLS) effort that I was involved with during my PhD. This paper in particular focuses on the impact that different baryonic processes can have on the global star-formation rate, amongst many other effects. Reference: Schaye, Dalla Vecchia, Booth, Wiersma, Theuns, Haas, Bertone, Duffy, McCarthy, vd Voort 2010 MNRAS 402 1536-1560
Read More
My first N-body simulation paper (as well as Letter) on the topic of "Dark matter halo concentrations in the Wilkinson Microwave Anisotropy Probe year 5 cosmology" when I was based at Leiden Observatory. It demonstrated a fascinating inverse relation between the concentration (compactness) of a dark matter object and the mass of said object. Reference: Duffy, Schaye, Kay, Dalla Vecchia 2008 MNRAS 390L 64D
Read More
