Who are we? The team is based in the Research School of Astronomy and Astrophysics on the Australian National University in Canberra.
The supernova survey and transient optical counterparts team:
SkyMapper Telescope operations: Chris Onken, Chris Wolf
The team and their science interests
Anais research interests focus on type Ia supernova (SNIa) cosmology and machine learning applications to cosmology. She is interested in both low and high redshift SNe Ia surveys. At low redshift, she is currently leading the photometric SkyMapper Transient Survey with the goal of providing a untargeted SNIa sample to obtain the low-z cosmology anchor, studying possible evidence of type Ia SN progenitors as well other interesting transient events. Möller also belongs to other surveys searching and studying SNe at high redshift such as the Dark Energy Survey (DES), the Australian counterpart,OzDES, and the SuperNova Legacy Survey (SNLS). In these surveys she is currently working in selection biases and photometric classification of supernovae.
Brad Tucker is an Astrophysicist/Cosmologist,and is currently working on projects aimed at understanding dark energy through a better use and understanding of supernovae. He studies early and multiwavelength observations of supernovae to learn about their physics and progenitors. Tucker is working on a variety of supernova surveys incl. the SkyMapper Supernova Survey, OzDES, ESSENCE (Equation of State: SupErNovae trace Cosmic Expansion) and the Carnegie Supernova Project. He is also the lead of the Kepler Extra-Galactic Survey, a NASA Kepler K2 key project to search for supernovae, black holes and other extragalactic transient objects.As well as working on these projects, Tucker frequently speaks to school groups and the general public about astronomy, and has regular segments on various radio stations and the Morning Show on Channel 7, talking about astronomy news and events. He has also developed a series of astronomy coins in conjunction with the Royal Australian Mint, re-developed the Mt Stromlo and Siding Spring Observatories’ Visitor Centres, and in 2015 led Australia’s World Record Stargazing event.
Bonnie’s work is primarily in using Type Ia supernovae (SNe Ia) as standard candles to measure distances. Looking into the past (at higher redshifts), these distances allow us to measure the expansion history of the Universe, and estimate cosmological parameters such as the Hubble constant, the matter density Ωm of the Universe, and the dark energy equation-of-state w. In particular, Bonnie works on precisely measuring uncertainties (errors) associated with SNe Ia. She is also interested in finding out what SkyMapper supernovae can tell us about peculiar velocities in the local Universe, and examining in detail at SMT16svj, a strange (rapidly-rising, slowly-declining) supernova discovered by SkyMapper.
Ashley Ruiter works on determining which kinds of double (binary) stars end up making transient events, in particular Type Ia supernovae. Type Ia supernovae are today's most important distance indicators in the Universe. Though it is widely agreed that a Type Ia supernova arises from an exploding white dwarf star that has gained 'too much' mass from a companion star, the mass of the exploding white dwarf and the nature of the companion (Sun-like, or another white dwarf, etc.) are unknown. By simulating millions of binary stars from birth to death, covering a range of initial conditions, Dr. Ruiter can pinpoint which types of binaries lead to Type Ia supernovae. These theoretical predictions help to interpret SkyMapper supernova data, thus making connections between individual explosive events and the properties of their host stellar population.
Ivo is primarily interested in the explosion mechanisms and the nucleosynthesis products of supernovae. Using state-of-the-art parallel codes, he is simulating the hydrodynamics of explosions of white dwarf stars powered by the runaway thermonuclear incineration of the combined mass of more than one solar mass of carbon and oxygen into more tightly bound nuclei, such as silicon, iron, or nickel. Ivo’s particular interests lie in calculating the detailed isotopic compositions of the elements forged in these stellar thermonuclear explosions. In addition to performing numerical calculations and simulations, Ivo is also using some of the world’s most sensitive integral field spectrographs at Siding Spring Observatory in New South Wales and at the Very Large Telescope in Chile to map and characterize the three-dimensional structure and chemical composition of the ejected matter in young core-collapse supernova remnants.
Seo-Won currently joined the SkyMapper team to contribute the improvement in the photometric analysis and calibration of both SkyMapper public and supernova surveys. He is working with alert follow-up programs, searching for optical counterparts of the elusive Fast Radio Bursts or Gravitational Waves. Such counterparts have never been identified, but must hold all the clues for the physics of these enigmatic phenomena. Also, he works with SkyMapper Transient search program to help classify and to better understand the properties of Type Ia supernovae or other transients (e.g., AGNs, flares or asteroids).
Fiona is interested in Type Ia supernovae (SNe Ia) that don’t behave the way we expect them to. In particular, she studies SN1991bg-like supernovae (SNe 91bg), which account for around 15% of all SNe Ia. SNe 91bg are much fainter than normal SNe Ia, and fade away much quicker. These supernovae are also thought to produce large quantities of antimatter (anti-electrons, or positrons) when they explode. Fiona has been trying to find clues about the types of stellar systems that end their lives as SNe 91bg by looking at the galaxies they occur in. She is interested in developing new techniques to identify and classify peculiar SNe Ia, including SNe 91bg, using only photometry (the kind of data SkyMapper collects). She is a member of the SkyMapper telescope team and helps to search and classify transient events found by the telescope.
Natalia E. Sommer
Nat primarily works with active galactic nuclei (AGN), or supermassive black holes. By observing these objects she is hoping to be able to use them to calculate distances to galaxies far out in our Universe. If this is possible, supermassive black holes could help us learn more about dark energy, and the way it has evolved over cosmological time. As part of the SkyMapper transient team, Nat is studying the supernovae observed by the survey, and will combine them together with the distances measured from supermassive black holes to constrain our understanding of dark energy in the best possible way.
Ryan is developing a balloon based, high altitude ultra violet survey telescope. The balloon will fly above the ozone layer to study a wide variety of exciting phenomena ranging from cosmology to exoplanet atmospheres. The telescope’s primary objective is to spot supernovae soon after they explode to help us understand the physics and objects involved in the colossal explosion. Ryan works with SkyMapper to help classify objects, with a particular interest in supernovae spotted soon after explosion.
Daniel is using machine learning to enable computers to automatically classify supernova spectra into their specific type, age, redshift and host-galaxy. Due to the unprecedented number of supernovae being observed by surveys such as SkyMapper, he is developing an accurate, fast, and automated classification software. Daniel is also interested in using supernovae for cosmology, and in particular, is combining Type Ia supernova measurements from SkyMapper with galaxy measurements from the TAIPAN survey. By using both datasets, we can learn more about the differences in the two probes of distance and can get a more accurate measurement of the local Hubble constant.
Patrick is an undergraduate at ANU currently completing a Bachelor of Advanced Science with a Physics Major and Astrophysics specialisation. He has worked with the Supernova team on projects involving the Supernova Transient Server, the search for Planet 9 and internal work involving their databases and website. He will be working with them on many other projects throughout the future.
Nataliea is primarily interested in the unique objects or “weird” object of the Universe. By looking through the supernova data collected by the ANU’s SkyMapper survey telescope, Nataliea hopes to investigate the weird supernova or “weirdos”, which is exploding stars that do fall into the current categories we have given to supernova. By looking at these objects she hopes to discover new types of supernova and ultimately help us further understand these fascinating explosions. Photo: Annabelle Lowson
Webpage Patrick Armstrong, Fang Yuan, Richard Scalzo,Anais Möller