Staff Profile

Dr. Joachim Harnois-Deraps is a cosmologist specialising in the study of dark matter, dark energy, massive neutrinos, baryon feedback mechanisms and modifications to the theory of gravity.  He is particularly interested in the technique of weak gravitational lensing, which measures the distortions on the shape of background galaxies by the foreground cosmic web.

Alone or in combination with other probes, weak lensing can reveal a wealth of information about our Universe, including maps of the invisible dark matter. 

He is part of the Kilo Degree Survey, LSST-DESC and Euclid, wherein he is developing cutting-edge techniques to better analyse cosmic shear data. His novel simulation-based methods can improve by a factor of three the precision on the dark energy equation of state.

This image represents a simulated mass map as detected with the technique of gravitational lensing. Over-plotted are the simulated dark matter haloes that live within the cosmic web, which themselves host galaxies observed by our telescopes.

Dr. Joachim Harnois-Deraps is an Ernest Rutherford Fellow at Newcastle University, and is leading the numerical simulation programme in many international weak lensing collaborations (KiDS, LSST and Euclid). You can find a list of his publications here.

He is the PI of the Scinet LIght-Cone Simulation suites (SLICS and cosmo-SLICS), a public series of over 1000 N-body runs ideally suited to estimate the signal and the uncertainty about cosmological measurement, including cosmic shear, galaxy-galaxy lensing, galaxy clustering and redshift space distortions -- they were central to 50+ journal papers to date, see https://slics.roe.ac.uk. 

I am teaching PHY2029 in the winter semester, and I am regularly looking for summer students, M.Sc. and Ph.D. Please get in touch if you are interested or intrigued by my research.