David Richard Harvey

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Using the largestmosaic of Hubble Space Telescope images around a galaxy cluster, we map the distribution of darkmatter throughout an similar to 6 x 6 Mpc(2) area centred on the clusterMS 0451-03 (z = 0.54, M-200 = 1.65 x 10(15) M-circle dot). Our joint st ...

We modify the chemo-dynamical code GEAR to simulate the impact of self-interacting dark matter (SIDM) on the observable quantities of 19 low-mass dwarf galaxies with a variety star-forming properties. We employ a relatively high, velocity independent cross ...

If dark matter interacts, even weakly, via non-gravitational forces, simulations predict that it will be preferentially scattered towards the trailing edge of the halo during collisions between galaxy clusters. This will temporarily create a non-symmetric ...

We update the publicly available weak lensing shear measurement algorithm pyRRG for the JWST, and apply it to UNCOVER DR1 imaging of galaxy cluster Abell 2744. At short wavelengths (

Galaxy cluster Abell 3827 hosts the stellar remnants of four almost equally bright elliptical galaxies within a core of radius 10 kpc. Such corrugation of the stellar distribution is very rare, and suggests recent formation by several simultaneous mergers. ...

Simulations of self-interacting dark matter predict that dark matter should lag behind galaxies during a collision. If the interaction is mediated by a high-mass force carrier, the distribution of dark matter can also develop asymmetric dark matter tails. ...

We explore how assuming that mass traces light in strong gravitational lensing models can lead to systematic errors in the predicted position of multiple images. Using a model based on the galaxy cluster MACS J0416 (z = 0.397) from the Hubble Frontier Fiel ...

The HST treasury programme BUFFALO provides extended wide-field imaging of the six Hubble Frontier Fields galaxy clusters. Here we present the combined strong and weak-lensing analysis of Abell 370, a massive cluster at z = 0.375. From the reconstructed to ...

We compared the total mass density profiles of three different types of galaxies using weak gravitational lensing: (i) 29 galaxies that host quasars at (z) over bar similar to 0.32 that are in a post-starburst quasar (PSQ) phase with high star formation in ...

We present a gravitational lensing and X-ray analysis of a massive galaxy cluster and its surroundings. The core of MACS J0717.5+3745 (M(R < 1Mpc) similar to 2 x 10(15) M-circle dot, z = 0.54) is already known to contain four merging components. We show th ...

We investigate the environment and line of sight (LoS) of the H0LiCOW (H-0 Lenses in COSMOGRAIL's Wellspring) lens B1608+656 using Subaru Suprime-Cam and the Hubble Space Telescope (HST) to perform a weak lensing analysis. We compare three different method ...

A striking signal of dark matter beyond the standard model is the existence of cores in the centre of galaxy clusters. Recent simulations predict that a brightest cluster galaxy ( BCG) inside a cored galaxy cluster will exhibit residual wobbling due to pre ...

Flux ratio anomalies in strong gravitationally lensed quasars constitute a unique way to probe the abundance of non-luminous dark matter haloes, and hence the nature of dark matter. In this paper, we identify double-imaged quasars as a statistically effici ...

We present a multiwavelength analysis of the core of the massive galaxy cluster MACS J0417.5-1154 (z = 0.441). Our analysis takes advantage of Very Large Telescope/Multi-Unit Spectroscopic Explorer observations which allowthe spectroscopic confirmation of ...

The massive substructures found in Abell 2744 by Jauzac et al. present a challenge to the cold dark matter paradigm due to their number and proximity to the cluster centre. We use one of the biggest N-body simulations, the Millennium XXL, to investigate th ...

We use a joint optical/X-ray analysis to constrain the geometry and history of the ongoing merging event in the massive galaxy cluster MACSJ0416.1-2403 (z = 0.397). Our investigation of cluster substructure rests primarily on a combined strong-and weak-len ...

Terrestrial particle accelerators collide charged particles, then watch the trajectory of outgoing debris - but they cannot manipulate dark matter. Fortunately, dark matter is the main component of galaxy clusters, which are continuously pulled together by ...

We present a joint optical/X-ray analysis of the massive galaxy cluster Abell 2744 (z = 0.308). Our strong- and weak-lensing analysis within the central region of the cluster, i.e. at R < 1 Mpc from the brightest cluster galaxy, reveals eight substructures ...

The distribution of mass in galaxy-scale strong gravitational lenses is often modelled as an elliptical power-law plus 'external shear', which notionally accounts for neighbouring galaxies and cosmic shear along our line of sight. A small amount of externa ...

Collisions between galaxy clusters provide a test of the nongravitational forces acting on dark matter. Dark matter's lack of deceleration in the "bullet cluster" collision constrained its self-interaction cross section sigma(DM)/m

David Richard Harvey

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The distribution of dark matter and gas spanning 6 Mpc around the post-merger galaxy cluster MS0451-03

The impact of cored density profiles on the observable quantities of dwarf spheroidal galaxies

Looking for dark matter trails in colliding galaxy clusters

Weak gravitational lensing measurements of Abell 2744 using JWST and shear measurement algorithm pyRRG-JWST

The behaviour of dark matter associated with four bright cluster galaxies in the 10 kpc core of Abell 3827

A test for skewed distributions of dark matter, and a possible detection in galaxy cluster Abell 3827

Systematic or signal? How dark matter misalignments can bias strong lensing models of galaxy clusters

Beyond the ultradeep frontier fields and legacy observations (BUFFALO): a high-resolution strong plus weak-lensing view of Abell 370

A weak lensing comparability study of galaxy mergers that host AGNs

Growing a 'cosmic beast': observations and simulations of MACS J0717.5+3745

H0LiCOW-XI. A weak lensing measurement of the external convergence in the field of the lensed quasar B1608+656 using HST and Subaru deep imaging

A detection of wobbling brightest cluster galaxies within massive galaxy clusters

Exploiting flux ratio anomalies to probe warm dark matter in future large-scale surveys

The core of the massive cluster merger MACS J0417.5-1154 as seen by VLT/MUSE

Abell 2744: too much substructure for Lambda CDM?

Hubble Frontier Fields: the geometry and dynamics of the massive galaxy cluster merger MACSJ0416.1-2403

Hydrodynamical simulations of merging galaxy clusters: giant dark matter particle colliders, powered by gravity

The extraordinary amount of substructure in the Hubble Frontier Fields cluster Abell 2744

Strong gravitational lensing's 'external shear' is not shear

The nongravitational interactions of dark matter in colliding galaxy clusters