Publications by David Richard Harvey

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

Richard Massey, David Richard Harvey, Mathilde Jauzac

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 ...

Oxford Univ Press2024

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

Richard Massey, David Richard Harvey

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 (

Oxford Univ Press2024

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

Richard Massey, David Richard Harvey

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 ...

Oxford Univ Press2024

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

David Richard Harvey, Mathilde Jauzac

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 ...

OXFORD UNIV PRESS2023

Data Downloaded via Parachute from a NASA Super-Pressure Balloon

Richard Massey, David Richard Harvey, Mathilde Jauzac, Lun Li

In April 2023, the superBIT telescope was lifted to the Earth's stratosphere by a helium-filled super-pressure balloon to acquire astronomical imaging from above (99.5% of) the Earth's atmosphere. It was launched from New Zealand and then, for 40 days, cir ...

MDPI2023

The BUFFALO HST Survey

Johan Richard, Céline Tchernin, Matthieu Schaller, Pascale Jablonka, Jean-Paul Richard Kneib, Huanyuan Shan, Hakim Atek, Richard Massey, David Richard Harvey, Mathilde Jauzac, Benjamin Yvan Alexandre Clement, Anja Von der Linden

The Beyond Ultra-deep Frontier Fields and Legacy Observations (BUFFALO) is a 101 orbit + 101 parallel Cycle 25 Hubble Space Telescope (HST) Treasury program taking data from 2018 to 2020. BUFFALO will expand existing coverage of the Hubble Frontier Fields ...

IOP PUBLISHING LTD2020

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

Jean-Paul Richard Kneib, Richard Massey, David Richard Harvey, Baptiste Philippe Klein, Mathilde Jauzac

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 ...

OXFORD UNIV PRESS2020

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

Georges Meylan, Frédéric Courbin, Vivien François Bonvin, David Richard Harvey, Olga Tihhonova, Austin Chandler Peel

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 ...

OXFORD UNIV PRESS2020

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

Alexey Boyarsky, Frédéric Courbin, Amélie Tamone, David Richard Harvey, Wessel Valkenburg

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 ...

2019

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

Johan Richard, Johannes Richard Cornelis Geerit Kruis, Jean-Paul Richard Kneib, Richard Massey, David Richard Harvey, Mathilde Jauzac

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 ...

OXFORD UNIV PRESS2019

Observable tests of self-interacting dark matter in galaxy clusters: BCG wobbles in a constant density core

Richard Massey, David Richard Harvey

Models of cold dark matter (CDM) predict that the distribution of dark matter in galaxy clusters should be cuspy, centrally concentrated. Constant density cores would be strong evidence for beyond CDM physics, such as self-interacting dark matter (SIDM). A ...

OXFORD UNIV PRESS2019

Dark matter dynamics in Abell 3827: new data consistent with standard cold dark matter

Johan Richard, Frédéric Courbin, Richard Massey, Rémy Elie Joseph, David Richard Harvey, Mathilde Jauzac

2018

H0LiCOW VIII. A weak-lensing measurement of the external convergence in the field of the lensed quasar HE0435-1223

Georges Meylan, Frédéric Courbin, Vivien François Bonvin, David Richard Harvey, Olga Tihhonova

2018

The shape of galaxy dark matter haloes in massive galaxy clusters: insights from strong gravitational lensing

Richard Massey, David Richard Harvey, Mathilde Jauzac

2018

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

Elena Cristina Dalla Vecchia, Matthieu Schaller, Jean-Paul Richard Kneib, Richard Massey, David Richard Harvey, Matthew Aaron Robertson, Barney Frederick Drake, Mathilde Jauzac

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 ...

OXFORD UNIV PRESS2018

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

Yves Revaz, Loïc Hausammann, David Richard Harvey

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 ...

OXFORD UNIV PRESS2018

Abell 2744: too much substructure for Lambda CDM?

Richard Massey, David Richard Harvey, Mathilde Jauzac

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 ...

Oxford Univ Press2017

Potential Recoiling Supermassive Black Hole, CXO J101527.2+625911

David Richard Harvey

We have carried out a systematic search for recoiling supermassive black holes (rSMBH) using the Chandra Source and SDSS Cross-Match Catalog. From the survey, we have detected a potential rSMBH, CXO J101527.2 +625911, at z = 0.3504. The source CXO J101527. ...

Iop Publishing Ltd2017

Looking for dark matter trails in colliding galaxy clusters

Jean-Paul Richard Kneib, Richard Massey, David Richard Harvey

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 ...

Oxford Univ Press2017

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

Frédéric Courbin, Richard Massey, Rémy Elie Joseph, David Richard Harvey, Mathilde Jauzac

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. ...

Oxford Univ Press2017