Professor OMAR ALMAINI's Outputs (63)

Growing up in a megalopolis: environmental effects on galaxy evolution in a supercluster at z∼0.65 in UKIDSS UDS (2018)
Journal Article
Galametz, A., Pentericci, L., Castellano, M., Mendel, T., Hartley, W. G., Fossati, M., Finoguenov, A., Almaini, O., Beifiori, A., Fontana, A., Grazian, A., Scodeggio, M., & Kocevski, D. D. (2018). Growing up in a megalopolis: environmental effects on galaxy evolution in a supercluster at z∼0.65 in UKIDSS UDS. Monthly Notices of the Royal Astronomical Society, 475(3), https://doi.org/10.1093/mnras/sty095

We present a large-scale galaxy structure Cl J021734-0513 at z ∼ 0.65 discovered in the UKIDSS UDS field, made of ∼ 20 galaxy groups and clusters, spreading over 10 Mpc. We report on a VLT/VIMOS spectroscopic follow-up program that, combined with pas... Read More about Growing up in a megalopolis: environmental effects on galaxy evolution in a supercluster at z∼0.65 in UKIDSS UDS.

SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES): faint-end counts at 450 μm (2017)
Journal Article
Wang, W.-H., Lin, W.-C., Lim, C.-F., Smail, I., Chapman, S. C., Zheng, X. Z., Shim, H., Kodama, T., Almaini, O., Ao, Y., Blain, A. W., Bourne, N., Bunker, A. J., Chang, Y.-Y., Chao, D. C.-Y., Chen, C.-C., Clements, D. L., Conselice, C. J., Cowley, W. I., Dannerbauer, H., …Wardlow, J. L. (2017). SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES): faint-end counts at 450 μm. Astrophysical Journal, 850(1), https://doi.org/10.3847/1538-4357/aa911b

The SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES) is a three-year JCMT Large Program aiming to reach the 450 μm confusion limit in the COSMOS-CANDELS region to study a representative sample of the high-redshift far-infrared galaxy population that g... Read More about SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES): faint-end counts at 450 μm.

The UKIRT Hemisphere Survey: definition and J-band data release (2017)
Journal Article
Dye, S., Lawrence, A., Read, M., Fan, X., Kerr, T., Varricatt, W., Furnell, K., Edge, A., Irwin, M., Hambly, N., Lucas, P., Almaini, O., Chambers, K., Green, R., Hewett, P., Liu, M., McGreer, I., Best, W., Zhang, Z., Sutorius, E., …Tedds, J. (2018). The UKIRT Hemisphere Survey: definition and J-band data release. Monthly Notices of the Royal Astronomical Society, 473(4), 5113-5125. https://doi.org/10.1093/mnras/stx2622

This paper defines the UK Infra-Red Telescope (UKIRT) Hemisphere Survey (UHS) and release of the remaining ∼12 700 deg2 of J-band survey data products. The UHS will provide continuous J- and K-band coverage in the Northern hemisphere from a declinati... Read More about The UKIRT Hemisphere Survey: definition and J-band data release.

CANDELS: Elevated black hole growth in the progenitors of compact quiescent galaxies at z ∼ 2 (2017)
Journal Article
Kocevski, D. D., Barro, G., Faber, S., Dekel, A., Somerville, R. S., Young, J. A., Williams, C. C., McIntosh, D. H., Georgakakis, A., Hasinger, G., Nandra, K., Civano, F., Alexander, D. M., Almaini, O., Conselice, C. J., Donley, J. L., Ferguson, H. C., Giavalisco, M., Grogin, N. A., Hathi, N., …Yan, H. (2017). CANDELS: Elevated black hole growth in the progenitors of compact quiescent galaxies at z ∼ 2. Astrophysical Journal, 846(2), https://doi.org/10.3847/1538-4357/aa8566

We examine the fraction of massive (M* > 1010 M) compact star-forming galaxies (cSFGs) that host an active galactic nucleus (AGN) at z ~ 2. These cSFGs are likely the direct progenitors of the compact quiescent galaxies observed at this epoch, which... Read More about CANDELS: Elevated black hole growth in the progenitors of compact quiescent galaxies at z ∼ 2.

Massive post-starburst galaxies at z > 1 are compact proto-spheroids (2017)
Journal Article
Almaini, O., Wild, V., Maltby, D. T., Hartley, W. G., Simpson, C., Hatch, N. A., McLure, R. J., Dunlop, J. S., & Rowlands, K. (2017). Massive post-starburst galaxies at z > 1 are compact proto-spheroids. Monthly Notices of the Royal Astronomical Society, 472(2), 1401-1412. https://doi.org/10.1093/mnras/stx1957

We investigate the relationship between the quenching of star formation and the structural transformation of massive galaxies, using a large sample of photometrically-selected poststarburst galaxies in the UKIDSS UDS field. We find that post-starburs... Read More about Massive post-starburst galaxies at z > 1 are compact proto-spheroids.

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., Hasinger, G., Maltby, D. T., Muldrew, S. I., & Simpson, C. (2017). Enhancement of AGN in a protocluster at z=1.6. Monthly Notices of the Royal Astronomical Society, 470(2), 2170-2178. https://doi.org/10.1093/mnras/stx1315

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 about Enhancement of AGN in a protocluster at z=1.6.

A consistent measure of the merger histories of massive galaxies using close-pair statistics I: Major mergers at z < 3:5 (2017)
Journal Article
Mundy, C. J., Conselice, C. J., Duncan, K. J., Almaini, O., Häußler, B., & Hartley, W. G. (2017). A consistent measure of the merger histories of massive galaxies using close-pair statistics I: Major mergers at z < 3:5. Monthly Notices of the Royal Astronomical Society, 470(3), 3507–3531. https://doi.org/10.1093/mnras/stx1238

We use a large sample of ∼350,000 galaxies constructed by combining the UKIDSS UDS, VIDEO/CFHT-LS, UltraVISTA/COSMOS and GAMA survey regions to probe the major merging histories of massive galaxies (>1010 M⊙) at 0.005<z<3.5. We use a method adapted f... Read More about A consistent measure of the merger histories of massive galaxies using close-pair statistics I: Major mergers at z < 3:5.

The SCUBA-2 Cosmology Legacy Survey: multi-wavelength properties of ALMA-identified submillimeter galaxies in UKIDSS UDS (2017)
Journal Article
Simpson, J., Smail, I., Swinbank, A., Ivison, R., Dunlop, J., Geach, J., Almaini, O., Arumugam, V., Bremer, M., Chen, C.-C., Conselice, C. J., Coppin, K., Farrah, D., Ibar, E., Hartley, W., Ma, C., Michałowski, M., Scott, D., Spaans, M., Thomson, A., & Werf, P. V. D. (2017). The SCUBA-2 Cosmology Legacy Survey: multi-wavelength properties of ALMA-identified submillimeter galaxies in UKIDSS UDS. Astrophysical Journal, 839(1), Article 58. https://doi.org/10.3847/1538-4357/aa65d0

We present a multi-wavelength analysis of 52 submillimeter galaxies (SMGs), identified using ALMA 870 μm continuum imaging in a pilot program to precisely locate bright SCUBA-2-selected submillimeter sources in the UKIDSS Ultra Deep Survey (UDS) fiel... Read More about The SCUBA-2 Cosmology Legacy Survey: multi-wavelength properties of ALMA-identified submillimeter galaxies in UKIDSS UDS.

The SCUBA-2 Cosmology Legacy Survey: 850 μm maps, catalogues and number counts (2016)
Journal Article
Serjeant, S., Geach, J. E., Dunlop, J. S., Halpern, M., Smail, I., van der Werf, P., Alexander, D. M., Almaini, O., Aretxaga, I., Arumugam, V., Asboth, V., Banerji, M., Beanlands, J., Best, P. N., Blain, A. W., Birkinshaw, M., Chapin, E. L., Chapman, S. C., Chen, C.-C., Chrysostomou, A., …Zemcov, M. (2017). The SCUBA-2 Cosmology Legacy Survey: 850 μm maps, catalogues and number counts. Monthly Notices of the Royal Astronomical Society, 465(2), 1789-1806. https://doi.org/10.1093/mnras/stw2721

We present a catalogue of ∼3000 submillimetre sources detected (≥3.5σ) at 850 μm over ∼5 deg2 surveyed as part of the James Clerk Maxwell Telescope (JCMT) SCUBA-2 Cosmology Legacy Survey (S2CLS). This is the largest survey of its kind at 850 μm, incr... Read More about The SCUBA-2 Cosmology Legacy Survey: 850 μm maps, catalogues and number counts.

Faint submillimeter galaxies identified through their optical/near-infrared colors: 1. Spatial clustering and halo masses (2016)
Journal Article
Chen (陳建州), C.-C., Smail, I., Swinbank, A., Simpson, J. M., Almaini, O., Conselice, C. J., Hartley, W. G., Mortlock, A., Simpson, C., & Wilkinson, A. (2016). Faint submillimeter galaxies identified through their optical/near-infrared colors: 1. Spatial clustering and halo masses. Astrophysical Journal, 831(1), https://doi.org/10.3847/0004-637X/831/1/91

The properties of submillimeter galaxies (SMGs) that are fainter than the confusion limit of blank-field single-dish surveys (S850  2 mJy) are poorly constrained. Using a newly developed color selection technique, Optical-Infrared Triple Color (OIRT... Read More about Faint submillimeter galaxies identified through their optical/near-infrared colors: 1. Spatial clustering and halo masses.

Galaxy Zoo: quantitative visual morphological classifications for 48 000 galaxies from CANDELS (2016)
Journal Article
Simmons, B., Lintott, C., Willett, K. W., Masters, K. L., Kartaltepe, J. S., Häußler, B., Kaviraj, S., Krawczyk, C., Kruk, S., McIntosh, D. H., Smethurst, R. J., Nichol, R. C., Scarlata, C., Schawinski, K., Conselice, C. J., Almaini, O., Ferguson, H. C., Fortson, L., Hartley, W., Kocevski, D., …Wiklind, T. (2017). Galaxy Zoo: quantitative visual morphological classifications for 48 000 galaxies from CANDELS. Monthly Notices of the Royal Astronomical Society, 464(4), https://doi.org/10.1093/mnras/stw2587

We present quantified visual morphologies of approximately 48 000 galaxies observed in three Hubble Space Telescope legacy fields by the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) and classified by participants in the Ga... Read More about Galaxy Zoo: quantitative visual morphological classifications for 48 000 galaxies from CANDELS.

The SCUBA-2 Cosmology Legacy Survey: The clustering of submillimetre galaxies in the UKIDSS UDS field (2016)
Journal Article
Wilkinson, A., Almaini, O., Chen, C. C., Smail, I., Arumugam, V., Blain, A., Chapin, E. L., Chapman, S. C., Conselice, C. J., Cowley, W. I., Dunlop, J. S., Farrah, D., Geach, J., Hartley, W. G., Ivison, R. J., Maltby, D. T., Michałowski, M. J., Mortlock, A., Scott, D., Simpson, C., …Wild, V. (2017). The SCUBA-2 Cosmology Legacy Survey: The clustering of submillimetre galaxies in the UKIDSS UDS field. Monthly Notices of the Royal Astronomical Society, 464(2), 1380-1392. https://doi.org/10.1093/mnras/stw2405

© 2016 The Authors. Submillimetre galaxies (SMGs) are among the most luminous dusty galaxies in the Universe, but their true nature remains unclear; are SMGs the progenitors of the massive elliptical galaxies we see in the local Universe, or are they... Read More about The SCUBA-2 Cosmology Legacy Survey: The clustering of submillimetre galaxies in the UKIDSS UDS field.

Exploring the progenitors of brightest cluster galaxies at z ∼ 2 (2016)
Journal Article
Zhao, D., Conselice, C. J., Aragón-Salamanca, A., Almaini, O., Hartley, W. G., Lani, C., Mortlock, A., & Old, L. (2017). Exploring the progenitors of brightest cluster galaxies at z ∼ 2. Monthly Notices of the Royal Astronomical Society, 464(2), 1393-1414. https://doi.org/10.1093/mnras/stw2406

We present a new method for tracing the evolution of brightest cluster galaxies (BCGs) from z ∼ 2 to z ∼ 0. We conclude on the basis of semi-analytical models that the best method to select BCG progenitors at z ∼ 2 is a hybrid environmental density a... Read More about Exploring the progenitors of brightest cluster galaxies at z ∼ 2.

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. (2017). The impact of protocluster environments at z = 1.6. Monthly Notices of the Royal Astronomical Society, 464(1), 876-884. https://doi.org/10.1093/mnras/stw2359

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 about The impact of protocluster environments at z = 1.6.

The evolution of post-starburst galaxies from z=2 to 0.5 (2016)
Journal Article
Wild, V., Almaini, O., Dunlop, J., Simpson, C., Rowlands, K., Bowler, R., Maltby, D., & McLure, R. (2016). The evolution of post-starburst galaxies from z=2 to 0.5. Monthly Notices of the Royal Astronomical Society, 463(1), 832-844. https://doi.org/10.1093/mnras/stw1996

We present the evolution in the number density and stellar mass functions of photometrically selected post-starburst galaxies in the UKIDSSUltraDeep Survey,with redshifts of 0.5<z<2 and stellar masses log (M/M�) >10. We find that this transitionary s...

The evolution of galaxies at constant number density: a less biased view of star formation, quenching, and structural formation (2016)
Journal Article
Ownsworth, J. R., Conselice, C. J., Mundy, C. J., Mortlock, A., Hartley, W. G., Duncan, K., & Almaini, O. (2016). The evolution of galaxies at constant number density: a less biased view of star formation, quenching, and structural formation. Monthly Notices of the Royal Astronomical Society, 461(1), https://doi.org/10.1093/mnras/stw1207

Due to significant galaxy contamination and impurity in stellar mass selected samples (up to 95 per cent from z = 0–3), we examine the star formation history, quenching time-scales, and structural evolution of galaxies using a constant number density... Read More about The evolution of galaxies at constant number density: a less biased view of star formation, quenching, and structural formation.

The identification of post-starburst galaxies at z∼1 using multiwavelength photometry: a spectroscopic verification (2016)
Journal Article
Maltby, D. T., Almaini, O., Wild, V., Hatch, N. A., Hartley, W. G., Simpson, C., McLure, R. J., Dunlop, J., Rowlands, K., & Cirasuolo, M. (2016). The identification of post-starburst galaxies at z∼1 using multiwavelength photometry: a spectroscopic verification. Monthly Notices of the Royal Astronomical Society: Letters, 459(1), Article L114-L118. https://doi.org/10.1093/mnrasl/slw057

Despite decades of study, we still do not fully understand why some massive galaxies abruptly switch off their star formation in the early Universe, and what causes their rapid transition to the red sequence. Post-starburst galaxies provide a rare op... Read More about The identification of post-starburst galaxies at z∼1 using multiwavelength photometry: a spectroscopic verification.

The SCUBA-2 Cosmology Legacy Survey: multiwavelength counterparts to 103 submillimeter galaxies in the UKIDSS-UDS field (2016)
Journal Article
Chen, C.-C., Smail, I., Ivison, R. J., Arumugam, V., Almaini, O., Conselice, C. J., Geach, J. E., Hartley, W. G., Ma, C.-J., Mortlock, A., Simpson, C., Simpson, J. M., Swinbank, A. M., Aretxaga, I., Blain, A., Chapman, S. C., Dunlop, J. S., Farrah, D., Halpern, M., Michałowski, M. J., …Zavala, J. A. (2016). The SCUBA-2 Cosmology Legacy Survey: multiwavelength counterparts to 103 submillimeter galaxies in the UKIDSS-UDS field. Astrophysical Journal, 820(2), 82. https://doi.org/10.3847/0004-637x/820/2/82

We present multiwavelength identifications for the counterparts of 1088 submillimeter sources detected at 850 μm in the SCUBA-2 Cosmology Legacy Survey study of the UKIRT Infrared Deep Sky Survey-Ultra-Deep Survey (UDS) field. By utilizing an Atacama... Read More about The SCUBA-2 Cosmology Legacy Survey: multiwavelength counterparts to 103 submillimeter galaxies in the UKIDSS-UDS field.

The structure and evolution of a forming galaxy cluster at z = 1.62 (2016)
Journal Article
J. Conselice, C., G. Hartley, W., A. Cooke, E., I. Muldrew, S., A. Hatch, N., Hatch, N. A., Muldrew, S. I., Cooke, E. A., Hartley, W. G., Almaini, O., J. Simpson, C., & Conselice, C. J. (2016). The structure and evolution of a forming galaxy cluster at z = 1.62. Monthly Notices of the Royal Astronomical Society, 459(1), 387-401. https://doi.org/10.1093/mnras/stw602

We present a comprehensive picture of the Cl0218.3-0510 protocluster at $z=1.623$ across 10 co-moving Mpc. Using filters that tightly bracket the Balmer and 4000 Angstrom breaks of the protocluster galaxies we obtain precise photometric redshifts res... Read More about The structure and evolution of a forming galaxy cluster at z = 1.62.

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., Brodwin, M., Muldrew, S. I., Almaini, O., Conselice, C. J., Eisenhardt, P. R., Hartley, W. G., Jarvis, M., Seymour, N., & Stanford, S. A. (2015). The formation history of massive cluster galaxies as revealed by CARLA. Monthly Notices of the Royal Astronomical Society, 452(3), 2318-2336. https://doi.org/10.1093/mnras/stv1413

© 2015 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. 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... Read More about The formation history of massive cluster galaxies as revealed by CARLA.