Dr Pat Scott

ARC Future Fellowship

School of Mathematics and Physics
Faculty of Science
pat.scott@uq.edu.au
+61 7 336 53129

Overview

I'm a particle and astroparticle phenomenologist, which basically means a universal busybody. I stick my nose into particle theory and experiment, cosmology, solar and stellar physics, high energy astrophysics, statistics, computational physics, supercomputing and other things - usually two or three at a time.

Have a look at some of my papers for details of the fun I get up to. I lead the GAMBIT Community, a bunch of 60-odd other like-minded busybodies from all over the HEP-astro diaspora, trying to put together all the pieces of the jigsaw puzzle that is the search for physics Beyond the Standard Model (of particle physics). A big part of that is dark matter, but really, we'll take any new particles we can get.

I've been at UQ since 2019. Before that I was an STFC Ernest Rutherford Fellow and Senior Lecturer in the Fundamental Physics Section at Imperial College, a Banting Fellow in the HEP Theory group at McGill University, a PhD student in the Cosmology, Astroparticle Physics and String Theory Group at the Oskar Klein Centre in Stockholm, and an Honours student at the Mt Stromlo Observatory at ANU in Canberra.

Research Interests

  • Physics Beyond the Standard Model
  • Particle physics theory and experiment
  • Cosmology, solar and stellar physics
  • High energy astrophysics
  • Statistics
  • Computational physics
  • Numerical analysis
  • Supercomputing
  • Machine learning

Publications

View all Publications

Grants

View all Grants

Supervision

  • Doctor Philosophy

View all Supervision

Available Projects

  • Dark matter interacts extremely weakly with regular matter, but it does still interact enough to scatter of nuclei occasionally in many models. The Sun sits in bath of dark matter particles, with many of them passing through it every day. Some dark matter particles would scatter off a nucleus in the Sun, and lose enough energy to become gravitationally bound to it. They would then return on bound orbits, scatter again and again, losing more energy and sinking down to the core of the Sun. In many models, they would then annihilate with each other, producing a shower of energetic particles. Those particles would include neutrinos, which travel straight through the Sun, and can be detected here on Earth using neutrino telescopes such as IceCube, Super-Kamiokande and ANTARES. The first part of the project is to combine the results of these three neutrino telescopes, to produce one of the strongest probes of interactions between dark matter and nuclei to date. The second part is to determine the projected sensitivity of the next generation of neutrino telescopes (KM3NeT, IceCube Gen2/Pingu, Hyper-Kamiokande), in order to build an analysis framework that will allow all three experiments to combine their results, and collaborators involved in the GAMBIT project (http://gambit.hepforge.org) to combine the results with those from all other experiments.

    Starting point: arxiv:1601.00653

  • Depending on exactly what went on in the early Universe, the first dark matter halos may have formed extremely early, when there was nothing to dirupt their growth into extremely dense structures. These objects, known as ultracompact minihalos (UCMHs) may still be around today. Searching for them is one of the best ways to probe what happenened on small scales in the early Universe, before the formation of the cosmic microwave background. The project is to

    - simulate the formation of UCMHs in the early Universe, in order to better understand just how compact they really should be,

    - improve searches for them with gamma rays and pulsar timing (as tested using the Square Kilometre Array radio telescope), and

    - use the results of those searches together with searches for primordial black holes to test theories of early Universe physics such as inflation.

    Starting points: arxiv:1110.2484, arxiv:1905.05766

  • Many of the simplest models for dark matter assume that its particles cannot interact with each other. However, the observational limits that we have on this (from the Bullet Cluster) actually still permit a relatively high self-interaction rate -- enough to possibly explain why we don't see that many cusps in dark matter density profiles (the "core-cusp problem"), why there are less satellite galaxies around our own than expected (the "missing satellite problem") and why small galaxies don't seem to have more stars (the "too big to fail problem"). The Global and Modular Beyond-the-Standard Model Inference Tool (GAMBIT; https://gambit.hepforge.org) is a large-scale project aimed at combining all relevant constraints on all of the most compelling models for dark matter and other new particles. The project is to implement predictions and observational constraints on self-interacting dark matter models within GAMBIT, including from the large-scale structure of the Universe, and to use them carry out the most complete tests to date of the self-interacting dark matter hypothesis.

    Starting points: arxiv:1705.07908, arxiv:1205.5809

View all Available Projects

Publications

Book Chapter

  • Grevesse, N., Asplund, M., Sauval, A. J. and Scott, P. (2010). The chemical composition of the Sun. Synergies between Solar and Stellar Modelling. (pp. 177-182) edited by Maria Pia Di Mauro, Daniela Cardini and Marcella Marconi.Dordrecht, The Netherlands: Springer Netherlands. doi:10.1007/978-90-481-9198-7_31

  • Grevesse, Nicolas, Asplund, Martin, Sauval, A. Jacques and Scott, Pat (2010). The new solar composition and the solar metallicity. The sun, the solar wind, and the heliosphere. (pp. 51-60) edited by Mari Paz Miralles and Jorge Sánchez Almeida.Dordrecht, The Netherlands: Springer Netherlands. doi:10.1007/978-90-481-9787-3_6

Journal Article

Conference Publication

  • Scott, Pat (2017). Dark matter theory: Implications and future prospects for fermi. 7th International Fermi Symposium, IFS 2017, Garmisch-Partenkirchen, Germany, 15 - 20 October 2017. Trieste, Italy :Sissa Medialab Srl. doi: 10.22323/1.312.0167

  • Beniwal, Ankit, Rajec, Filip, Savage, Christopher, Scott, Pat, Weniger, Christoph, White, Martin and Williams, Anthony G. (2016). Combined analysis of effective Higgs portal dark matter models. International Conference on High Energy Physics, Chicago, ILL, United States, 3-10 August 2016. Trieste, Italy :Sissa Medialab.

  • Grevesse, N., Asplund, M., Sauval, J. and Scott, P. (2013). Why GN93 should not be used anymore. Liège International Astrophysical Colloquium. Ageing Low Mass Stars: From Red Giants to White Dwarfs, Liège, Belgium, 9-13 July 2012. Les Ulis, France :E D P Sciences. doi: 10.1051/epjconf/20134301004

  • Scott, Pat, Bringmann, Torsten and Akrami, Yashar (2012). Constraints on small-scale cosmological perturbations from gamma-ray searches for dark matter. 12th International Conference on Topics in Astroparticle and Underground Physics, TAUP 2011, Munich, Germany, 5 - 9 September 2011. Bristol, United Kingdom :Institute of Physics Publishing. doi: 10.1088/1742-6596/375/1/032012

  • Rydberg, Claes-Erik, Zackrisson, Erik and Scott, Pat (2011). Can the James Webb Space Telescope detect isolated population III stars?. Cosmic Radiation Fields: Sources in the early Universe, Desy, Germany, 9-12 November 2010. Trieste, Italy :Sissa Medialab. doi: 10.22323/1.121.0026

  • Grevesse, N., Asplund, M., Sauval, A. J. and Scott, P. (2011). The chemical composition of the sun. International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas, Berkeley, CA, United States, 3-7 August 2010. Ottawa, ON, Canada :Canadian Science Publishing. doi: 10.1139/p10-119

  • Scott, Pat (2010). Dark stars: Structure, evolution and impacts upon the high-redshift Universe. Trieste, Italy :Sissa Medialab. doi: 10.22323/1.121.0021

  • Scott, Pat, Fairbairn, Malcolm and Edsjo, Joakim (2009). Impacts of WIMP dark matter upon stellar evolution: main-sequence stars. Identification of dark matter, Stockholm, Sweden, 18-22 August 2008. Trieste, Italy :Sissa Medialab. doi: 10.22323/1.064.0073

  • Scott, Pat, Fairbairn, Malcolm and Edsjo, Joakim (2009). Impacts of WIMP dark matter upon stellar evolution: main-sequence stars. Identification of dark matter, Stockholm, Sweden, 18-22 August 2008. Trieste, Italy :Sissa Medialab. doi: 10.22323/1.064.0073

  • Scott, Pat, Edjsö, Joakim and Fairbairn, Malcolm (2009). The DarkStars code: a publicly available dark stellar evolution package. 7th International Heidelberg Conference on Dark Matter in Astro and Particle Physics (DARK 2009), Christchurch, New Zealand, 18-24 January 2009. Hackensack, NJ, United States :World Scientific . doi: 10.1142/9789814293792_0024

  • Scott, P. C., Edsjö, J. and Fairbairn, M. (2008). Low mass stellar evolution with WIMP capture and annihilation. International Heidelberg Conference on Dark Matter in Astroparticle and Particle Physics, Sydney, Australia, 24-28 September 2007. World Scientific Publishing.

Other Outputs

Grants (Administered at UQ)

PhD and MPhil Supervision

Current Supervision

  • Doctor Philosophy — Principal Advisor

    Other advisors:

Possible Research Projects

Note for students: The possible research projects listed on this page may not be comprehensive or up to date. Always feel free to contact the staff for more information, and also with your own research ideas.

  • Dark matter interacts extremely weakly with regular matter, but it does still interact enough to scatter of nuclei occasionally in many models. The Sun sits in bath of dark matter particles, with many of them passing through it every day. Some dark matter particles would scatter off a nucleus in the Sun, and lose enough energy to become gravitationally bound to it. They would then return on bound orbits, scatter again and again, losing more energy and sinking down to the core of the Sun. In many models, they would then annihilate with each other, producing a shower of energetic particles. Those particles would include neutrinos, which travel straight through the Sun, and can be detected here on Earth using neutrino telescopes such as IceCube, Super-Kamiokande and ANTARES. The first part of the project is to combine the results of these three neutrino telescopes, to produce one of the strongest probes of interactions between dark matter and nuclei to date. The second part is to determine the projected sensitivity of the next generation of neutrino telescopes (KM3NeT, IceCube Gen2/Pingu, Hyper-Kamiokande), in order to build an analysis framework that will allow all three experiments to combine their results, and collaborators involved in the GAMBIT project (http://gambit.hepforge.org) to combine the results with those from all other experiments.

    Starting point: arxiv:1601.00653

  • Depending on exactly what went on in the early Universe, the first dark matter halos may have formed extremely early, when there was nothing to dirupt their growth into extremely dense structures. These objects, known as ultracompact minihalos (UCMHs) may still be around today. Searching for them is one of the best ways to probe what happenened on small scales in the early Universe, before the formation of the cosmic microwave background. The project is to

    - simulate the formation of UCMHs in the early Universe, in order to better understand just how compact they really should be,

    - improve searches for them with gamma rays and pulsar timing (as tested using the Square Kilometre Array radio telescope), and

    - use the results of those searches together with searches for primordial black holes to test theories of early Universe physics such as inflation.

    Starting points: arxiv:1110.2484, arxiv:1905.05766

  • Many of the simplest models for dark matter assume that its particles cannot interact with each other. However, the observational limits that we have on this (from the Bullet Cluster) actually still permit a relatively high self-interaction rate -- enough to possibly explain why we don't see that many cusps in dark matter density profiles (the "core-cusp problem"), why there are less satellite galaxies around our own than expected (the "missing satellite problem") and why small galaxies don't seem to have more stars (the "too big to fail problem"). The Global and Modular Beyond-the-Standard Model Inference Tool (GAMBIT; https://gambit.hepforge.org) is a large-scale project aimed at combining all relevant constraints on all of the most compelling models for dark matter and other new particles. The project is to implement predictions and observational constraints on self-interacting dark matter models within GAMBIT, including from the large-scale structure of the Universe, and to use them carry out the most complete tests to date of the self-interacting dark matter hypothesis.

    Starting points: arxiv:1705.07908, arxiv:1205.5809

  • The simplest model for dark matter is another scalar particle, with no charges under any of the Standard Model gauge groups. There are many very different constraints on this model. The project is to extend existing combinations of those constraints to also consider stability of the electroweak vacuum in the case that singlet gets a vacuum expectation value of its own, and to improve existing treatments of unitarity and perturbativity.

    Starting points: arXiv:1806.11281, arXiv:1805.07306

  • Thermal effects after inflation can cause the Universe to 'jump' from one vacuum to another. Depending on what the vacua look like, and how hot the Universe gets after inflation (i.e. the 'reheating temperature'), this is more or less likely. The project will look at what bounds this places on the reheating temperature for some simple but viable beyond-the-Standard Model particle theories possessing multiple minima in their potential, namely Type II/III/X/Y two-Higgs doublet models.

    Starting points: arXiv:1705.03677, arXiv:1307.1477

  • New singlet particles with a very small mixing with the Higgs boson would be produced by decays from other heavier particles in the early Universe, in the so-called 'freeze-in' process. This process is expected to change quite a bit if the singlets have substantial self-interactions. The project is to explore those changes, and to build a general framework for calculating the resulting cosmological abundance of such singlets, so that it can be combined with constraints from astroparticle physics (worked out by an existing student) in a global statistical fit of such models.

    Starting point: arXiv:1812.07585