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HST grism confirmation of 16 structures at 1.4 < z < 2.8 from the Clusters Around Radio-Loud AGN (CARLA) survey (2018)
Journal Article
Noirot, G., Stern, D., Mei, S., Wylezalek, D., Cooke, E. A., De Breuck, C., …Stanford, S. A. (2018). HST grism confirmation of 16 structures at 1.4 < z < 2.8 from the Clusters Around Radio-Loud AGN (CARLA) survey. Astrophysical Journal, 859(1), doi:10.3847/1538-4357/aabadb

We report spectroscopic results from our 40-orbit Hubble Space Telescope slitless grism spectroscopy program observing the 20 densest Clusters Around Radio-Loud AGN (CARLA) candidate galaxy clusters at 1.4 less than z less than 2.8. These candidate r... Read More

Galaxy evolution in protoclusters (2017)
Journal Article
Muldrew, S. I., Hatch, N. A., & Cooke, E. A. (in press). Galaxy evolution in protoclusters. Monthly Notices of the Royal Astronomical Society, doi:10.1093/mnras/stx2454. ISSN 0035-8711

We investigate galaxy evolution in protoclusters using a semi-analytic model applied to the Millennium Simulation, scaled to a Planck cosmology. We show that the model reproduces the observed behaviour of the star formation history (SFH) both in prot... Read More

Enhancement of AGN in a protocluster at z=1.6 (2017)
Journal Article
Krishnan, C., Hatch, N. A., Almaini, O., Kocevski, D., Cooke, E. A., Hartley, W. G., …Simpson, C. (2017). Enhancement of AGN in a protocluster at z=1.6. Monthly Notices of the Royal Astronomical Society, 470(2), doi:10.1093/mnras/stx1315. ISSN 0035-8711

We investigate the prevalence of AGN in the high-redshift protocluster Cl 0218.3–0510 at z = 1.62. Using imaging from the Chandra X-ray Telescope, we find a large overdensity of AGN in the protocluster; a factor of 23±9 times the field density of AGN... Read More

HST grism confirmation of two z ~ 2 structures from the clusters around radio-loud AGN (CARLA) survey (2016)
Journal Article
Noirot, G., Vernet, J., De Breuck, C., Wylezalek, D., Galametz, A., Stern, D., …Stanford, S. A. (2016). HST grism confirmation of two z ~ 2 structures from the clusters around radio-loud AGN (CARLA) survey. Astrophysical Journal, 830(2), doi:10.3847/0004-637X/830/2/90. ISSN 0004-637X

Using Hubble Space Telescope slitless grism data, we report the spectroscopic confirmation of two distant structures at z ~ 2 associated with powerful high-redshift radio-loud active galactic nuclei (AGNs). These rich structures, likely (forming) clu... Read More

The impact of protocluster environments at z = 1.6 (2016)
Journal Article
Hatch, N. A., Cooke, E. A., Muldrew, S. I., Hartley, W. G., Almaini, O., Conselice, C. J., & Simpson, C. (in press). The impact of protocluster environments at z = 1.6. Monthly Notices of the Royal Astronomical Society, 464(1), doi:10.1093/mnras/stw2359. ISSN 0035-8711

We investigate the effects of dense environments on galaxy evolution by examining how the properties of galaxies in the z = 1.6 protocluster Cl 0218.3−0510 depend on their location. We determine galaxy properties using spectral energy distribution fi... Read More

ALMA finds dew drops in the dusty spider’s web (2016)
Journal Article
Gullberg, B., Lehnert, M. D., De Breuck, C., Branchu, S., Dannerbauer, H., Drouart, G., …Vernet, J. (2016). ALMA finds dew drops in the dusty spider’s web. Astronomy and Astrophysics, 591, doi:10.1051/0004-6361/201527647. ISSN 1432-0746

We present 0.̋5 resolution ALMA detections of the observed 246 GHz continuum, [CI] 3P2→3P1 fine structure line ([CI]2–1), CO(7–6), and H2O lines in the z = 2.161 radio galaxy MRC1138-262, the so-called Spiderweb galaxy. We detect strong [CI]2–1 emiss... Read More

HST imaging of the dusty filaments and nucleus swirl in NGC4696 at the centre of the Centaurus Cluster (2016)
Journal Article
Fabian, A., Walker, S., Russell, H., Pinto, C., Canning, R., Salome, P., …Reynolds, C. (in press). HST imaging of the dusty filaments and nucleus swirl in NGC4696 at the centre of the Centaurus Cluster. Monthly Notices of the Royal Astronomical Society, 461(1), doi:10.1093/mnras/stw1350. ISSN 0035-8711

Narrow-band HST imaging has resolved the detailed internal structure of the 10 kpc diameter H α+[N II] emission line nebulosity in NGC4696, the central galaxy in the nearby Centaurus cluster, showing that the dusty, molecular, filaments have a width... Read More

The structure and evolution of a forming galaxy cluster at z = 1.62 (2016)
Journal Article
Hatch, N. A., Muldrew, S. I., Cooke, E. A., Hartley, W. G., Almaini, O., Simpson, C., & Conselice, C. J. (in press). The structure and evolution of a forming galaxy cluster at z = 1.62. Monthly Notices of the Royal Astronomical Society, 459(1), doi:10.1093/mnras/stw602. ISSN 0035-8711

We present a comprehensive picture of the Cl 0218.3−0510 protocluster at z = 1.623 across 10 comoving Mpc. Using filters that tightly bracket the Balmer and 4000 Å breaks of the protocluster galaxies we obtain precise photometric redshifts resulting... Read More

A mature galaxy cluster at z= 1.58 around the radio galaxy 7C 1753+6311 (2016)
Journal Article
Cooke, E. A., Hatch, N. A., Stern, D., Rettura, A., Brodwin, M., Galametz, A., …Jarvis, M. (2016). A mature galaxy cluster at z= 1.58 around the radio galaxy 7C 1753+6311. Astrophysical Journal, 816(2), doi:10.3847/0004-637X/816/2/83. ISSN 0004-637X

We report on the discovery of a z = 1.58 mature cluster around the high-redshift radio galaxy 7C 1753+6311, first identified in the Clusters Around Radio-loud active galactic nuclei survey. Two-thirds of the excess galaxies within the central 1 Mpc l... Read More

What are protoclusters? – Defining high-redshift galaxy clusters and protoclusters (2015)
Journal Article
Muldrew, S. I., Hatch, N. A., & Cooke, E. A. (in press). What are protoclusters? – Defining high-redshift galaxy clusters and protoclusters. Monthly Notices of the Royal Astronomical Society, 452(3), doi:10.1093/mnras/stv1449. ISSN 0035-8711

We explore the structures of protoclusters and their relationship with high-redshift clusters using the Millennium Simulation combined with a semi-analytic model. We find that protoclusters are very extended, with 90 per cent of their mass spread acr... Read More

The formation history of massive cluster galaxies as revealed by CARLA (2015)
Journal Article
Cooke, E. A., Hatch, N. A., Rettura, A., Wylezalek, D., Galametz, A., Stern, D., …Stanford, S. (2015). The formation history of massive cluster galaxies as revealed by CARLA. Monthly Notices of the Royal Astronomical Society, 452(3), doi:10.1093/mnras/stv1413. ISSN 0035-8711

We use a sample of 37 of the densest clusters and protoclusters across 1.3 ≤ z ≤ 3.2 from the Clusters Around Radio-Loud AGN (CARLA) survey to study the formation of massive cluster galaxies. We use optical i′-band and infrared 3.6 and 4.5 μm images... Read More

Why z > 1 radio-loud galaxies are commonly located in protoclusters (2014)
Journal Article
Hatch, N. A., Wylezalek, D., Kurk, J., Stern, D., De Breuck, C., Jarvis, M., …Stevens, J. (2014). Why z > 1 radio-loud galaxies are commonly located in protoclusters. Monthly Notices of the Royal Astronomical Society, 445(1), doi:10.1093/mnras/stu1725. ISSN 0035-8711

Distant powerful radio-loud active galactic nuclei (RLAGN) tend to reside in dense environments and are commonly found in protoclusters at z > 1.3. We examine whether this occurs because RLAGN are hosted by massive galaxies, which preferentially resi... Read More