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Institute of Astronomy

 

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The main focus of my scientific research is the study of galaxy formation and evolution, 1 billion years after the Big Bang (12 billion years ago which is 7 billion years before the solar system formed) focusing on the discovery of high redshift quasars powered by the accretion of matter onto supermassive black holes. I work on the discovery of quasars and active galaxies that host supermassive black holes, the determination of their space densities, star formation rates and how and when they are born and grow. I have also worked on the experimental determination of the rate of gravitational deceleration of the Universe. This work resulted in the unexpected discovery that the expansion of the Universe is accelerating and not decelerating as expected.

McMahon is the Principal Investigator (PI) of the ambitious VISTA Hemisphere Survey(VHS) which is a deep near Infra-Red sky survey project. The observational project has been been awarded 300+ clear nights on the  4.2m ESO VISTA telescope in Chile. For a number of years, McMahon led the quasar science working group in the Dark Energy Survey(DES) project which built a very large CCD camera (DECAM) and was been awarded over 500 nights on the US CTIO 4m telescope in Chile to use this camera to observe the sky at optical wavelength.

DIRAC Bio statement: McMahon has over 25 years of experience in data intensive analysis and computational research, national and international project science, project management and data management in ground and space-based data intensive projects involving ESA (XMM-Newton), ESO (VISTA, 4MOST) and STFC (CASU, DES, LSST, IRIS, UKSRC). He has been a member of the DIRAC Project Board  and PI of the DIRAC Cambridge Data Intensive service since 2017.

A common theme of his research is the development of data intensive observational techniques that exploit technological developments to explore the boundaries of the observable distant Universe. McMahon works closely with other researchers and engineers on emerging and cutting edge technology. They try to ensure that they minimise the use of unnecessary bleeding edge technology. McMahon makes progress by learning from his own mistakes and the mistakes and experience of both younger and older colleagues, who generously support him on his journey of discovery.

Biography

Courtesy of Google Bard: Richard McMahon is an astronomer who peers into the distant Universe, studying objects formed around a few hundred million years after the Big Bang before the Sun and Solar System formed. He hunts for giant black holes in the hearts of bright "quasars" and young galaxies. By understanding how these giant black holes grow, he hopes to unravel the mysteries of their formation and how they shaped the Universe as we know it. He also played a key role in a groundbreaking unexpected discovery - measuring the accelerating expansion of the Universe, showing that galaxies are rushing apart faster and faster. Before this discovery, astronomers expected that the expansion rate to be slowing down due to the gravity of all the material in the Universe.

A common theme of his research is the development of data intensive observational techniques that exploit technological developments to explore the boundaries of the observable distant Universe. McMahon works closely with other researchers and engineers on emerging and cutting edge technology. They try to ensure that they minimise the use of unnecessary bleeding edge technology. McMahon makes progress by learning from his own mistakes and the mistakes and experience of both younger and older colleagues, who generously support him on his journey of discovery.

Career

  • 2012 - Present: Professor of Astronomy, Institute of Astronomy, University of Cambridge
  • 2017 - 2022: Director and Head of Department, Institute of Astronomy, University of Cambridge
  • 2013 - 2017: Deputy Director, Institute of Astronomy, University of Cambridge
  • 2001 - 2012: Reader in Observational Astronomy, Institute of Astronomy, University of Cambridge
  • 2000 - 2001: John Couch Astronomer, University of Cambridge
  • 1999 - 2001: University Lecturer,  Institute of Astronomy, University of Cambridge
  • 1994 - 1999: Assistant Director of Research, Institute of Astronomy, University of Cambridge
  • 1991 - 2001: Royal Society University Research Fellow, Institute of Astronomy, University of Cambridge
  • 1986 - 1991: Research Associate, Institute of Astronomy, University of Cambridge

Education

  • PhD, Institute of Astronomy, University of Cambridge; Supervisor: Cyril Hazard
  • Postgraduate Certification in Secondary Education (Physics), University of Cambridge
  • BSc (Hons) Physics, Queen's University  Belfast 

Awards and Prizes

  • 2015 Breakthrough Prize In Fundamental Physics for the discovery of the accelerating Universe (as a member of the Supernova Cosmology Project )
  • 2007 Gruber Cosmology Prize for the discovery of the accelerating Universe (as a member of the Supernova Cosmology Project)
  • 2001 Clarivate Web of Science Highly Cited Researcher
  • 2000 John Couch Adams Astronomer
  • 1999 PPARC Opportunity Scheme award for the Dark Ages ‘Z’ Lyman Explorer (DAZLE)
  • 1991 Royal Society University Research Fellowship

Publications

Key publications: 

Google Scholar page

  1. Gravitationally lensed quasars in Gaia - IV. 150 new lenses, quasar pairs, and projected quasars, Lemon, C., et al, 2023, MNRAS, 520, 3305.
  2. STRIDES: a 3.9 per cent measurement of the Hubble constant from the strong lens system DES J0408-5354, Shajib, A.J. et al., 2020, MNRAS, 494,6072
  3. Gravitationally lensed quasars in Gaia - III. 22 new lensed quasars from Gaia data release 2, Lemon, C., Auger, M., McMahon, R.G., 2019, MNRAS, 483, 4242
  4. Eight new luminous z ≥ 6 quasars discovered via SED model fitting of VISTA, WISE and Dark Energy Survey Year 1 observations, Reed, S., McMahon, R.G et al., 2017, MNRAS, 468, 4702
  5. VDES J2325-5229 a z = 2.7 gravitationally lensed quasar discovered discovered using morphology-independent supervised machine learning, Ostrovski, F., McMahon, R.G. et al., 2017, MNRAS, 465, 4325 .
  6. Heavily reddened quasars at z~2 in the UKIDSS Large Area Survey: a transitional phase in AGN evolution, Banerji, M., McMahon, R.G. et al, 2012, MNRAS ,427, 2275
  7. Detection of Atomic Carbon [C II] 158 μm and Dust Emission from a z = 7.1 Quasar Host Galaxy, Venemans, McMahon et al., 2012, ApJL, 751L, 25
  8. A luminous quasar at a redshift of z = 7.085, Mortlock, D et al., 2011, Nature, 474, 616
  9. The discovery of the first luminous z ~ 6 quasar in the UKIDSS Large Area Survey; Venemans, B., McMahon R.G. et al, 2007, MNRAS, 376L, 76; 
  10. DAzLE: the dark ages z (redshift) Lyman-α Explorer; Horton et al., 2004, SPIE,5492, 1022.
  11. The evolution of ΩHI and the epoch of formation of damped Lyman α absorbers, Peroux, C. McMahon R.G. et al, 2003, MNRAS, 346L, 1103.
  12. Lyman break galaxies and the star formation rate of the Universe at z~ 6; Stanway, Elizabeth R.; Bunker, Andrew J.; McMahon, Richard G., 2003, MNRAS, 342, 439: 
  13. The far-infrared-submillimetre spectral energy distribution of high-redshift quasars, Priddey, R. and McMahon, R.G., 2001, MNRAS, 324P, 17.
  14. Optical Counterparts for 70,000 Radio Sources: APM Identifications for the FIRST Radio Survey; McMahon, Richard G.; White, Richard L.; Helfand, David J.; Becker, Robert H., 2002, ApJS, 143, 1.
  15. Measurements of Omega and Lambda from 42 High-Redshift Supernovae, Perlmutter S. et al, 1999, ApJ, 517, 565.
  16. Discovery of radio-loud quasars with z = 4.72 and z = 4.01; Hook, Isobel M.; McMahon, Richard G., 1998, MNRAS, 294, 7.
  17. Detection of Lyman-α emitting galaxies at redshift z = 4.55; Hu, Esther; McMahon Richard G., 1996, Nature, 382, 231.
  18. Evolution of neutral gas at high redshift: implications for the epoch of galaxy formation Storrie-Lombardi, L. J.; McMahon, R. G.; Irwin, M. J., 1996, MNRAS, 283, 79
  19. 1.25-mm continuum observations of very high-redshift QSOs: Is there dust at redshift  z = 4.69?, McMahon, R.G. et al, 1994, MNRAS, 267L, 9.
  20. The variability of optically selected quasars, Hook, I.M., McMahon, R.G., Boyle, B.J & Irwin. M.J. 1994, MNRAS, 268, 305 .

Other Professional Activities

Selected National and International roles

  • 2022 – Present: UK Square Kilometre Array Regional Centre (UKSRC);  Member of Project Board and Delivery Board
  • 2019 - Present: STFC IRIS project: Cambridge PI and member of IRIS Delivery Board
  • 2017 – Present: STFC DiRAC HPC: Chair of Cambridge-Leicester Data Intensive Service Management Board
  • 2017 – Present: STFC DiRAC HPC: Member of Project Board and PI Of Cambridge DIRAC Data Intensive Service
  • 2015  Present:  LSST-UK Executive Group member
  • 2013 2021: 4MOST Extragalactic Project Scientist

 

Selected Departmental and University responsibilities and roles

  • Director and Head of Department of Institute of Astronomy (2017-2022)
  • Deputy Director of Institute of Astronomy (2013-2017)
  • Various IT and Computing related committees
    • Chair of Computing Oversight Committee
    • Chair of School of Physical Sciences IT Committee
  • Member of the Information Services Committee Operations Sub-commitee
Professor of Astronomy

Affiliations

Collaborator profiles: 
Classifications: 
Person keywords: 
Galaxy
Black Hole