Ian Harrison
(he/him)
Research Associate
Astronomy Instrumentation Group
Cardiff Hub for Astrophysics Research and Technology
School of Physics and Astronomy
- HarrisonI@cardiff.ac.uk
- Queen's Buildings - North Building, Room N/3.20A, 5 The Parade, Newport Road, Cardiff, CF24 3AA
Overview
I am currently a Research Associate in cosmology in the School of Physics and Astronomy at Cardiff University.
I now have a few different research interests in observational and statistical cosmology, but my primary area of work is in developing cross-correlation methods between the Cosmic Microwave Background and other observables for the Simons Observatory.
I have worked on weak gravitational lensing, both in the radio with the SuperCLASS survey and the future SKAO Telescope, and in the optical with the Dark Energy Survey (DES). I am also interested in novel ways of combining radio and gravitational wave data to do cosmology, and in cosmology with galaxy cluster number counts. I am a founding member of the SkyPy Collaboration, which aims to create forward models for coherent simulation of astronomical observables across all wavebands(!).
Publication
2024
- Qu, F. J. et al. 2024. The Atacama Cosmology Telescope: A measurement of the DR6 CMB lensing power spectrum and its implications for structure growth. Astrophysical Journal 962(2), article number: 112. (10.3847/1538-4357/acfe06)
- Madhavacheril, M. S. et al. 2024. The Atacama Cosmology Telescope: DR6 gravitational lensing map and cosmological parameters. Astrophysical Journal 962(2), article number: 113. (10.3847/1538-4357/acff5f)
- Marques, G. et al. 2024. Cosmological constraints from the tomography of DES-Y3 galaxies with CMB lensing from ACT DR4. Journal of Cosmology and Astroparticle Physics 2024(1), article number: 33. (10.1088/1475-7516/2024/01/033)
2023
- Anbajagane, D. et al. 2023. Beyond the 3rd moment: a practical study of using lensing convergence CDFs for cosmology with DES Y3. Monthly Notices of the Royal Astronomical Society 526(4), pp. 5530-5554. (10.1093/mnras/stad3118)
- Sánchez, C. et al. 2023. The Dark Energy Survey Year 3 high-redshift sample: Selection, characterization, and analysis of galaxy clustering. Monthly Notices of the Royal Astronomical Society 525(3), pp. 3896–3922. (10.1093/mnras/stad2402)
- Shaikh, S., Harrison, I. and Calabrese, E. 2023. Cosmology from cross-correlation of ACT-DR4 CMB lensing and DES-Y3 cosmic shear. [Online]. arXiv. (10.48550/ARXIV.2309.04412) Available at: https://arxiv.org/abs/2309.04412
- Prat, J. et al. 2023. Non-local contribution from small scales in galaxy-galaxy lensing: Comparison of mitigation schemes. Monthly Notices of the Royal Astronomical Society 522(1), pp. 412-425. (10.1093/mnras/stad847)
- Omori, Y. et al. 2023. Joint analysis of Dark Energy Survey Year 3 data and CMB lensing from SPT and Planck . I. Construction of CMB lensing maps and modeling choices. Physical Review D 107, article number: 23529. (10.1103/PhysRevD.107.023529)
- Chang, C. et al. 2023. Joint analysis of Dark Energy Survey Year 3 data and CMB lensing from SPT and Planck . II. Cross-correlation measurements and cosmological constraints. Physical Review D 107(2), article number: 23530. (10.1103/PhysRevD.107.023530)
- Abbott, T. et al. 2023. Joint analysis of Dark Energy Survey Year 3 data and CMB lensing from SPT and Planck . III. Combined cosmological constraints. Physical Review D 107, article number: 23531. (10.1103/PhysRevD.107.023531)
- Lovell, C. C., Harrison, I., Harikane, Y., Tacchella, S. and Wilkins, S. M. 2023. Extreme value statistics of the halo and stellar mass distributions at high redshift: are JWST results in tension with ΛCDM?. Monthly Notices of the Royal Astronomical Society 518(2), pp. 2511–2520. (10.1093/mnras/stac3224)
2022
- Doux, C. et al. 2022. Dark energy survey year 3 results: cosmological constraints from the analysis of cosmic shear in harmonic space. Monthly Notices of the Royal Astronomical Society 515(2), pp. 1942-1972. (10.1093/mnras/stac1826)
- Secco, L. F. et al. 2022. Dark Energy Survey year 3 results: three-point shear correlations and mass aperture moments. Physical Review D 105(10), article number: 103537. (10.1103/PhysRevD.105.103537)
2013
- Harrison, I. 2013. Cosmology with extreme galaxy clusters. PhD Thesis, Cardiff University.
2012
- Harrison, I. and Coles, P. 2012. Testing cosmology with extreme galaxy clusters. Monthly Notices of the Royal Astronomical Society: Letters 421(1), pp. L19-L23. (10.1111/j.1745-3933.2011.01198.x)
2011
- Harrison, I. and Coles, P. 2011. Exact extreme value statistics and the halo mass function. Monthly Notices of the Royal Astronomical Society: Letters 418(1), pp. L20-L24. (10.1111/j.1745-3933.2011.01134.x)
Articles
- Qu, F. J. et al. 2024. The Atacama Cosmology Telescope: A measurement of the DR6 CMB lensing power spectrum and its implications for structure growth. Astrophysical Journal 962(2), article number: 112. (10.3847/1538-4357/acfe06)
- Madhavacheril, M. S. et al. 2024. The Atacama Cosmology Telescope: DR6 gravitational lensing map and cosmological parameters. Astrophysical Journal 962(2), article number: 113. (10.3847/1538-4357/acff5f)
- Marques, G. et al. 2024. Cosmological constraints from the tomography of DES-Y3 galaxies with CMB lensing from ACT DR4. Journal of Cosmology and Astroparticle Physics 2024(1), article number: 33. (10.1088/1475-7516/2024/01/033)
- Anbajagane, D. et al. 2023. Beyond the 3rd moment: a practical study of using lensing convergence CDFs for cosmology with DES Y3. Monthly Notices of the Royal Astronomical Society 526(4), pp. 5530-5554. (10.1093/mnras/stad3118)
- Sánchez, C. et al. 2023. The Dark Energy Survey Year 3 high-redshift sample: Selection, characterization, and analysis of galaxy clustering. Monthly Notices of the Royal Astronomical Society 525(3), pp. 3896–3922. (10.1093/mnras/stad2402)
- Prat, J. et al. 2023. Non-local contribution from small scales in galaxy-galaxy lensing: Comparison of mitigation schemes. Monthly Notices of the Royal Astronomical Society 522(1), pp. 412-425. (10.1093/mnras/stad847)
- Omori, Y. et al. 2023. Joint analysis of Dark Energy Survey Year 3 data and CMB lensing from SPT and Planck . I. Construction of CMB lensing maps and modeling choices. Physical Review D 107, article number: 23529. (10.1103/PhysRevD.107.023529)
- Chang, C. et al. 2023. Joint analysis of Dark Energy Survey Year 3 data and CMB lensing from SPT and Planck . II. Cross-correlation measurements and cosmological constraints. Physical Review D 107(2), article number: 23530. (10.1103/PhysRevD.107.023530)
- Abbott, T. et al. 2023. Joint analysis of Dark Energy Survey Year 3 data and CMB lensing from SPT and Planck . III. Combined cosmological constraints. Physical Review D 107, article number: 23531. (10.1103/PhysRevD.107.023531)
- Lovell, C. C., Harrison, I., Harikane, Y., Tacchella, S. and Wilkins, S. M. 2023. Extreme value statistics of the halo and stellar mass distributions at high redshift: are JWST results in tension with ΛCDM?. Monthly Notices of the Royal Astronomical Society 518(2), pp. 2511–2520. (10.1093/mnras/stac3224)
- Doux, C. et al. 2022. Dark energy survey year 3 results: cosmological constraints from the analysis of cosmic shear in harmonic space. Monthly Notices of the Royal Astronomical Society 515(2), pp. 1942-1972. (10.1093/mnras/stac1826)
- Secco, L. F. et al. 2022. Dark Energy Survey year 3 results: three-point shear correlations and mass aperture moments. Physical Review D 105(10), article number: 103537. (10.1103/PhysRevD.105.103537)
- Harrison, I. and Coles, P. 2012. Testing cosmology with extreme galaxy clusters. Monthly Notices of the Royal Astronomical Society: Letters 421(1), pp. L19-L23. (10.1111/j.1745-3933.2011.01198.x)
- Harrison, I. and Coles, P. 2011. Exact extreme value statistics and the halo mass function. Monthly Notices of the Royal Astronomical Society: Letters 418(1), pp. L20-L24. (10.1111/j.1745-3933.2011.01134.x)
Thesis
- Harrison, I. 2013. Cosmology with extreme galaxy clusters. PhD Thesis, Cardiff University.
Websites
- Shaikh, S., Harrison, I. and Calabrese, E. 2023. Cosmology from cross-correlation of ACT-DR4 CMB lensing and DES-Y3 cosmic shear. [Online]. arXiv. (10.48550/ARXIV.2309.04412) Available at: https://arxiv.org/abs/2309.04412
Biography
I obtained an MSci from Imperial College London in Physics with Theoretical Physics in 2010 and a PhD in Astrophysics from Cardiff University in 2013. During my PhD I worked under the supervision of Prof Peter Coles on cosmology with extreme value statistics.
Since then I have been a Research Associate at the University of Manchester from 2013 to 2021 (and remain a visitor there). I was also a long-term visitor and then Postdoctoral Research Assistant at the University of Oxford from 2018 to 2021.
Research themes
Specialisms
- Cosmology and extragalactic astronomy