Dr Laura Wolz

ABOUT ME

I am a cosmologist working as a Presidential Fellow at the Jodrell-Bank Centre for Astrophysics at the University of Manchester. Until 2019, I was part of the Astrophysics group of the University of Melbourne as a Discovery Early Career Research Award Fellow funded by the Australian Research Council. Previously, I have been employed as a CAASTRO postdoctoral research associate. I did my PhD work at University College London, graduating in 2014. I am originally from Munich, Germany, where I studied Physics.

My field of research is cosmology with radio observations, particularly using a technique called HI intensity mapping. I am the co-chair of the Square Kilometre Array Cosmology Science Working Group since 2018 and also co-chair the HI intensity Mapping Focus Group within.

I am passionate about making everyone feel welcome in science and astrophysics and have been part of diversity and inclusion committees and many initiatves on these topics. I have been speaker at multiple Girls in Physics events, both in the UK and Australia and find immense joy in bringing astrophysics and cosmology to a diverse audience.

I offer MPhys and PhD projects in Astrophysics at the University of Manchester, please contact me if you are interested in studying with me.

Contact me via laura.wolz AT manchester.ac.uk

Address: Alan Turing 3.121 - The University of Manchester, Oxford Rd, Manchester M13 9PL, UK

INTERESTS

All pictures on this page were taken at the 2018 Aspen summer conference on Perfect Pixels. Accurate Astrophysics. Correct Cosmology. The title of this conference reflects quite accurately my approach to research within HI intensity mapping. I aim to understand how imperfections, such as foreground residuals or beam systematics in the observational data from radio telescopes can impact our interpretations. I also research how the emission of HI gas depends on the underlying astrophysics of galaxy evolution. Finally, I set this into context on how cosmology analysis can be affected by these effects.

Cosmology

Square Kilometre Array

HI Intensity Mapping

Cosmologists are trying to understand the entire history of the Universe, from the beginning through the different stages galaxy formation and evolution. After the Big Bang the whole Universe expanded while cooling down, and the speed of the expansion slowed down with time. After about 7 billion years, half of the age of the Universe, the expansion started accelerating which is counter-intuitive from what we would expect to happen from gravitational theories. We call the force driving the acceleration Dark Energy and it is one of the greatest challenges to reveal the origin of Dark Energy. From the complete energy content of our current Universe, we know that only 4% are contributed by 'normal' matter and rest is made out of the Dark components, including Dark Energy and Dark Matter.

In traditional radio observations, astronomers employ very large dishes with diameters up to 100 metres to achieve a reasonable resolution and sensitivities. Radio interferometry can break the limitations of the single dishes by using an array of smaller dishes (around 15m) to achieve the same or better resolution than one much bigger dish telescope. The Square Kilometre Array(SKA) will be the ultimate radio observatory using hundreds of dishes and antennaes distributed over large areas in Australia and South Africa to achieve unseen resolution and sensitivity. The SKA will be used for a vast number of astronomical explorations including magnetic field studies, indirectly testing for gravitational waves via pulsar measurements and pushing towards detecting the epoch of reionization.

In this approach, we are trying to trace the cosmic distribution of galaxies and matter through their neutral hydrogen (HI) emission. Neutral hydrogen emits light with wavelengths of 21cm and is hence detectable with radio telescopes. The HI emission from individual, very distant objects is very weak, but the intensity mapping technique measures the emission from large regions, integrating over the emission of numerous galaxies. In theory, HI intensity maps can be obtained for alomost the whole history of our Universe using single dish telescopes or interferometers like the SKA. These maps will help us test our current cosmological model as well as understanding the role of neutral hydrogen gas in the fomation and evolution of galaxies.

PUBLICATIONS

You can find my most up-to-date list of articles through this link on the ADS.