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Where have all the low-metallicity galaxies gone? Tracing evolution in the mass-metallicity plane since a redshift of 0.7 (2023)
Journal Article
Zhou, S., Aragón-Salamanca, A., Merrifield, M., & Sampaio, V. M. (2023). Where have all the low-metallicity galaxies gone? Tracing evolution in the mass-metallicity plane since a redshift of 0.7. Monthly Notices of the Royal Astronomical Society, 527(2), 1935–1949. https://doi.org/10.1093/mnras/stad3330

Even over relatively recent epochs, galaxies have evolved significantly in their location in the mass–metallicity plane, which must be telling us something about the latter stages of galaxy evolution. In this paper, we analyse data from the LEGA-C su... Read More about Where have all the low-metallicity galaxies gone? Tracing evolution in the mass-metallicity plane since a redshift of 0.7.

The localization of galaxy groups in close proximity to galaxy clusters using cosmic web nodes (2023)
Journal Article
Cornwell, D. J., Kuchner, U., Gray, M. E., Aragón-Salamanca, A., Pearce, F. R., Cui, W., & Knebe, A. (2024). The localization of galaxy groups in close proximity to galaxy clusters using cosmic web nodes. Monthly Notices of the Royal Astronomical Society, 527(1), 23-34. https://doi.org/10.1093/mnras/stad3205

We investigate the efficacy of using the cosmic web nodes identified by the DisPerSE topological filament finder to systematically identify galaxy groups in the infall regions around massive clusters. The large random motions and infall velocities of... Read More about The localization of galaxy groups in close proximity to galaxy clusters using cosmic web nodes.

The co-evolution of strong AGN and central galaxies in different environments (2023)
Journal Article
Sampaio, V. M., Aragón-Salamanca, A., Merrifield, M. R., De Carvalho, R. R., Zhou, S., & Ferreras, I. (2023). The co-evolution of strong AGN and central galaxies in different environments. Monthly Notices of the Royal Astronomical Society, 524(4), 5327–5339. https://doi.org/10.1093/mnras/stad2211

We exploit a sample of 80 000 Sloan Digital Sky Survey central galaxies to investigate the effect of active galactic nucleus (AGN) feedback on their evolution. We trace the demographics of optically selected AGN (Seyferts) as a function of their inte... Read More about The co-evolution of strong AGN and central galaxies in different environments.

The probability of identifying the cosmic web environment of galaxies around clusters motivated by the Weave Wide Field Cluster Survey (2023)
Journal Article
Cornwell, D. J., Aragón-Salamanca, A., Kuchner, U., Gray, M. E., Pearce, F. R., & Knebe, A. (2023). The probability of identifying the cosmic web environment of galaxies around clusters motivated by the Weave Wide Field Cluster Survey. Monthly Notices of the Royal Astronomical Society, 524(2), 2148–2160. https://doi.org/10.1093/mnras/stad1949

Upcoming wide-field spectroscopic surveys will observe galaxies in a range of cosmic web environments in and around galaxy clusters. In this paper, we test and quantify how successfully we will be able to identify the environment of individual galaxi... Read More about The probability of identifying the cosmic web environment of galaxies around clusters motivated by the Weave Wide Field Cluster Survey.

Are Milky-Way-like galaxies like the Milky Way? A view from SDSS-IV/MaNGA (2023)
Journal Article
Zhou, S., Aragón-Salamanca, A., Merrifield, M., Andrews, B. H., Drory, N., & Lane, R. R. (2023). Are Milky-Way-like galaxies like the Milky Way? A view from SDSS-IV/MaNGA. Monthly Notices of the Royal Astronomical Society, 521(4), 5810-5825. https://doi.org/10.1093/mnras/stad853

In this paper, we place the Milky Way (MW) in the context of similar-looking galaxies in terms of their star-formation and chemical evolution histories. We select a sample of 138 Milky Way analogues (MWAs) from the SDSS-IV/MaNGA survey based on their... Read More about Are Milky-Way-like galaxies like the Milky Way? A view from SDSS-IV/MaNGA.

The wide-field, multiplexed, spectroscopic facility WEAVE: Survey design, overview, and simulated implementation (2023)
Journal Article
Jin, S., Trager, S. C., Dalton, G. B., Aguerri, J. A. L., Drew, J. E., Falcón-Barroso, J., …Zurita, C. (2023). The wide-field, multiplexed, spectroscopic facility WEAVE: Survey design, overview, and simulated implementation. Monthly Notices of the Royal Astronomical Society, https://doi.org/10.1093/mnras/stad557

WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for the William Herschel Telescope, will see first light in late 2022. WEAVE comprises a new 2-degree field-of-view prime-focus corrector system, a nearly 1000-multiplex f... Read More about The wide-field, multiplexed, spectroscopic facility WEAVE: Survey design, overview, and simulated implementation.

Lessons learned from the two largest Galaxy morphological classification catalogues built by convolutional neural networks (2022)
Journal Article
Cheng, T. Y., Domínguez Sánchez, H., Vega-Ferrero, J., Conselice, C. J., Siudek, M., Aragón-Salamanca, A., …Scarpine, V. (2023). Lessons learned from the two largest Galaxy morphological classification catalogues built by convolutional neural networks. Monthly Notices of the Royal Astronomical Society, 518(2), 2794–2809. https://doi.org/10.1093/mnras/stac3228

We compare the two largest galaxy morphology catalogues, which separate early- and late-type galaxies at intermediate redshift. The two catalogues were built by applying supervised deep learning (convolutional neural networks, CNNs) to the Dark Energ... Read More about Lessons learned from the two largest Galaxy morphological classification catalogues built by convolutional neural networks.

The impact of environment on the lives of disc galaxies as revealed by SDSS-IV MaNGA (2022)
Journal Article
Zhou, S., Merrifield, M., Aragón-Salamanca, A., Brownstein, J. R., Drory, N., Yan, R., & Lane, R. R. (2022). The impact of environment on the lives of disc galaxies as revealed by SDSS-IV MaNGA. Monthly Notices of the Royal Astronomical Society, 517(3), 3723-3731. https://doi.org/10.1093/mnras/stac2913

Environment has long been known to have significant impact on the evolution of galaxies, but here we seek to quantify the subtler differences that might be found in disc galaxies, depending on whether they are isolated, the most massive galaxy in a g... Read More about The impact of environment on the lives of disc galaxies as revealed by SDSS-IV MaNGA.

Forecasting the success of the WEAVE Wide-Field Cluster Survey on the extraction of the cosmic web filaments around galaxy clusters (2022)
Journal Article
Cornwell, D. J., Kuchner, U., Aragón-Salamanca, A., Gray, M. E., Pearce, F. R., Aguerri, J. A. L., …Trager, S. C. (2022). Forecasting the success of the WEAVE Wide-Field Cluster Survey on the extraction of the cosmic web filaments around galaxy clusters. Monthly Notices of the Royal Astronomical Society, 517(2), 1678–1694. https://doi.org/10.1093/mnras/stac2777

Next-generation wide-field spectroscopic surveys will observe the infall regions around large numbers of galaxy clusters with high sampling rates for the first time. Here we assess the feasibility of extracting the large-scale cosmic web around clust... Read More about Forecasting the success of the WEAVE Wide-Field Cluster Survey on the extraction of the cosmic web filaments around galaxy clusters.

SDSS-IV MaNGA: the chemical co-evolution of gas and stars in spiral galaxies (2022)
Journal Article
Greener, M. J., Aragón-Salamanca, A., Merrifield, M., Peterken, T., Sazonova, E., Haggar, R., …Pan, K. (2022). SDSS-IV MaNGA: the chemical co-evolution of gas and stars in spiral galaxies. Monthly Notices of the Royal Astronomical Society, 516(1), 1275–1288. https://doi.org/10.1093/mnras/stac2355

We investigate archaeologically how the metallicity in both stellar and gaseous components of spiral galaxies of differing masses evolve with time, using data from the SDSS-IV MaNGA survey. For the stellar component, we can measure this evolution dir... Read More about SDSS-IV MaNGA: the chemical co-evolution of gas and stars in spiral galaxies.

SDSS-IV MaNGA: How the stellar populations of passive central galaxies depend on stellar and halo mass (2022)
Journal Article
Oyarzun, G. A., Bundy, K., Westfall, K. B., Tinker, J. L., Belfiore, F., Argudo-Fernandez, M., …Zhang, K. (2022). SDSS-IV MaNGA: How the stellar populations of passive central galaxies depend on stellar and halo mass. Astrophysical Journal, 933(1), Article 88. https://doi.org/10.3847/1538-4357/ac7048

We analyze spatially resolved and co-added SDSS-IV MaNGA spectra with signal-to-noise ratio ∼100 from 2200 passive central galaxies (z ∼ 0.05) to understand how central galaxy assembly depends on stellar mass (M*) and halo mass (Mh). We control for s... Read More about SDSS-IV MaNGA: How the stellar populations of passive central galaxies depend on stellar and halo mass.

SDSS-IV MaNGA: Cannibalism Caught in the Act - On the Frequency of Occurrence of Multiple Cores in Brightest Cluster Galaxies (2022)
Journal Article
Hsu, Y. H., Lin, Y. T., Huang, S., Nelson, D., Rodriguez-Gomez, V., Lai, H. T., …Schneider, D. P. (2022). SDSS-IV MaNGA: Cannibalism Caught in the Act - On the Frequency of Occurrence of Multiple Cores in Brightest Cluster Galaxies. Astrophysical Journal, 933(1), Article 61. https://doi.org/10.3847/1538-4357/ac6d66

Although it is generally accepted that massive galaxies form in a two-phased fashion, beginning with a rapid mass buildup through intense starburst activities followed by primarily dry mergers that mainly deposit stellar mass at outskirts, the late t... Read More about SDSS-IV MaNGA: Cannibalism Caught in the Act - On the Frequency of Occurrence of Multiple Cores in Brightest Cluster Galaxies.

Semi-analytic spectral fitting: simultaneously modelling the mass accumulation and chemical evolution in MaNGA spiral galaxies (2022)
Journal Article
Zhou, S., Merrifield, M., & Aragón-Salamanca, A. (2022). Semi-analytic spectral fitting: simultaneously modelling the mass accumulation and chemical evolution in MaNGA spiral galaxies. Monthly Notices of the Royal Astronomical Society, 513(4), 5446-5464. https://doi.org/10.1093/mnras/stac1279

We develop a novel semi-analytic spectral fitting approach to quantify the star-formation histories (SFHs) and chemical enrichment histories (ChEHs) of individual galaxies. We construct simple yet general chemical evolution models that account for ga... Read More about Semi-analytic spectral fitting: simultaneously modelling the mass accumulation and chemical evolution in MaNGA spiral galaxies.

The Seventeenth Data Release of the Sloan Digital Sky Surveys: Complete Release of MaNGA, MaStar, and APOGEE-2 Data (2022)
Journal Article
Abdurro’uf, Accetta, K., Aerts, C., Silva Aguirre, V., Ahumada, R., Ajgaonkar, N., …Zhu, K. (2022). The Seventeenth Data Release of the Sloan Digital Sky Surveys: Complete Release of MaNGA, MaStar, and APOGEE-2 Data. Astrophysical Journal Supplement, 259(2), Article 35. https://doi.org/10.3847/1538-4365/ac4414

This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (M... Read More about The Seventeenth Data Release of the Sloan Digital Sky Surveys: Complete Release of MaNGA, MaStar, and APOGEE-2 Data.

An inventory of galaxies in cosmic filaments feeding galaxy clusters: galaxy groups, backsplash galaxies, and pristine galaxies (2021)
Journal Article
Kuchner, U., Haggar, R., Aragón-Salamanca, A., Pearce, F. R., Gray, M. E., Rost, A., …Yepes, G. (2022). An inventory of galaxies in cosmic filaments feeding galaxy clusters: galaxy groups, backsplash galaxies, and pristine galaxies. Monthly Notices of the Royal Astronomical Society, 510(1), 581-592. https://doi.org/10.1093/mnras/stab3419

Galaxy clusters grow by accreting galaxies from the field and along filaments of the cosmic web. As galaxies are accreted they are affected by their local environment before they enter (pre-processing), and traverse the cluster potential. Observation... Read More about An inventory of galaxies in cosmic filaments feeding galaxy clusters: galaxy groups, backsplash galaxies, and pristine galaxies.

H α-based star formation rates in and around z ∼ 0.5 EDisCS clusters (2021)
Journal Article
Cooper, J. R., Rudnick, G. H., Brammer, G. G., Desjardins, T., Mann, J. L., Weiner, B. J., …Zaritsky, D. (2022). H α-based star formation rates in and around z ∼ 0.5 EDisCS clusters. Monthly Notices of the Royal Astronomical Society, 509(4), 5382-5398. https://doi.org/10.1093/mnras/stab3184

We investigate the role of environment on star formation rates (SFRs) of galaxies at various cosmic densities in well-studied clusters. We present the star-forming main sequence for 163 galaxies in four EDisCS clusters in the range 0.4 < z < 0.7. We... Read More about H α-based star formation rates in and around z ∼ 0.5 EDisCS clusters.

From blue cloud to red sequence: Evidence of morphological transition prior to star formation quenching (2021)
Journal Article
Sampaio, V. M., De Carvalho, R. R., Ferreras, I., Aragón Salamanca, A., & Parker, L. C. (2022). From blue cloud to red sequence: Evidence of morphological transition prior to star formation quenching. Monthly Notices of the Royal Astronomical Society, 509(1), 567-585. https://doi.org/10.1093/mnras/stab3018

We present a study of a sample of 254 clusters from the SDSS-DR7 Yang Catalogue and an auxiliary sample of field galaxies to perform a detailed investigation on how galaxy quenching depends on both environment and galaxy stellar mass. Our samples are... Read More about From blue cloud to red sequence: Evidence of morphological transition prior to star formation quenching.

Galaxy Morphological Classification Catalogue of the Dark Energy Survey Year 3 data with Convolutional Neural Networks (2021)
Journal Article
Cheng, T., Conselice, C. J., Aragón-Salamanca, A., Aguena, M., Allam, S., Andrade-Oliveira, F., …To, C. (2021). Galaxy Morphological Classification Catalogue of the Dark Energy Survey Year 3 data with Convolutional Neural Networks. Monthly Notices of the Royal Astronomical Society, 507(3), 4425-4444. https://doi.org/10.1093/mnras/stab2142

We present in this paper one of the largest galaxy morphological classification catalogues to date, including over 20 million of galaxies, using the Dark Energy Survey (DES) Year 3 data based on Convolutional Neural Networks (CNN). Monochromatic i-ba... Read More about Galaxy Morphological Classification Catalogue of the Dark Energy Survey Year 3 data with Convolutional Neural Networks.

Beyond the Hubble Sequence - Exploring Galaxy Morphology with Unsupervised Machine Learning (2021)
Journal Article
Cheng, T., Huertas-Company, M., Conselice, C. J., Aragón-Salamanca, A., Robertson, B. E., & Ramachandra, N. (2021). Beyond the Hubble Sequence - Exploring Galaxy Morphology with Unsupervised Machine Learning. Monthly Notices of the Royal Astronomical Society, 503(3), 4446-4465. https://doi.org/10.1093/mnras/stab734

We explore unsupervised machine learning for galaxy morphology analyses using a combination of feature extraction with a vector-quantised variational autoencoder (VQ-VAE) and hierarchical clustering (HC). We propose a new methodology that includes: (... Read More about Beyond the Hubble Sequence - Exploring Galaxy Morphology with Unsupervised Machine Learning.

Cosmic filaments in galaxy cluster outskirts: quantifying finding filaments in redshift space (2021)
Journal Article
Kuchner, U., Aragón-Salamanca, A., Rost, A., Pearce, F. R., Gray, M. E., Cui, W., …Yepes, G. (2021). Cosmic filaments in galaxy cluster outskirts: quantifying finding filaments in redshift space. Monthly Notices of the Royal Astronomical Society, 503(2), 2065-2076. https://doi.org/10.1093/mnras/stab567

Inferring line-of-sight distances from redshifts in and around galaxy clusters is complicated by peculiar velocities, a phenomenon known as the "Fingers of God" (FoG). This presents a significant challenge for finding filaments in large observational... Read More about Cosmic filaments in galaxy cluster outskirts: quantifying finding filaments in redshift space.

Size, shade or shape? The contribution of galaxies of different types to the star-formation history of the Universe from SDSS-IV MaNGA (2021)
Journal Article
Peterken, T., Aragón-Salamanca, A., Merrifield, M., Avila-Reese, V., Boardman, N. F., Sánchez, H. D., …Brownstein, J. R. (2021). Size, shade or shape? The contribution of galaxies of different types to the star-formation history of the Universe from SDSS-IV MaNGA. Monthly Notices of the Royal Astronomical Society, 502(3), 3128–3143. https://doi.org/10.1093/mnras/stab268

SDSS-IV MaNGA: the “G-dwarf problem” revisited (2021)
Journal Article
Greener, M. J., Merrifield, M., Aragón-Salamanca, A., Peterken, T., Andrews, B., & Lane, R. R. (2021). SDSS-IV MaNGA: the “G-dwarf problem” revisited. Monthly Notices of the Royal Astronomical Society: Letters, 502(1), L95–L98. https://doi.org/10.1093/mnrasl/slab012

The levels of heavy elements in stars are the product of enhancement by previous stellar generations, and the distribution of this metallicity among the population contains clues to the process by which a galaxy formed. Most famously, the “G-dwarf pr... Read More about SDSS-IV MaNGA: the “G-dwarf problem” revisited.

SDSS-IV MaNGA: when is morphology imprinted on galaxies? (2020)
Journal Article
Peterken, T., Merrifield, M., Aragón-Salamanca, A., Avila-Reese, V., Boardman, N. F., Drory, N., & Lane, R. R. (2021). SDSS-IV MaNGA: when is morphology imprinted on galaxies?. Monthly Notices of the Royal Astronomical Society: Letters, 500(1), L42-L46. https://doi.org/10.1093/mnrasl/slaa179

It remains an open question as to how long ago the morphology that we see in a present-day galaxy was typically imprinted. Studies of galaxy populations at different redshifts reveal that the balance of morphologies has changed over time, but such sn... Read More about SDSS-IV MaNGA: when is morphology imprinted on galaxies?.

Formation of S0s in extreme environments II: the star-formation histories of bulges, discs and lenses (2020)
Journal Article
Johnston, E. J., Aragón-Salamanca, A., Fraser-McKelvie, A., Merrifield, M., Häußler, B., Coccato, L., …Sheen, Y. (2021). Formation of S0s in extreme environments II: the star-formation histories of bulges, discs and lenses. Monthly Notices of the Royal Astronomical Society, 500(3), 4193-4212. https://doi.org/10.1093/mnras/staa2838

Different processes have been proposed to explain the formation of S0s, including mergers, disc instabilities, and quenched spirals. These processes are expected to dominate in different environments, and thus leave characteristic footprints in the k... Read More about Formation of S0s in extreme environments II: the star-formation histories of bulges, discs and lenses.

SDSS-IV MaNGA: Spatially resolved star formation in barred galaxies (2020)
Journal Article
Fraser-McKelvie, A., Aragón-Salamanca, A., Merrifield, M., Masters, K., Nair, P., Emsellem, E., …Neumann, J. (2020). SDSS-IV MaNGA: Spatially resolved star formation in barred galaxies. Monthly Notices of the Royal Astronomical Society, https://doi.org/10.1093/mnras/staa1416

A novel wave-energy device is presented. Both a preliminary proof-of-principle of a working, scaled laboratory version of the energy device is shown as well as the derivation and analysis of a comprehensive mathematical and numerical model of the new... Read More about SDSS-IV MaNGA: Spatially resolved star formation in barred galaxies.

SDSS-IV MaNGA: Excavating the fossil record of stellar populations in spiral galaxies (2020)
Journal Article
Peterken, T., Merrifield, M., Aragón-Salamanca, A., Fraser-McKelvie, A., Avila-Reese, V., Riffel, R., …Drory, N. (2020). SDSS-IV MaNGA: Excavating the fossil record of stellar populations in spiral galaxies. Monthly Notices of the Royal Astronomical Society, https://doi.org/10.1093/mnras/staa1303

We perform a “fossil record” analysis for ≈800 low-redshift spiral galaxies, using STARLIGHT applied to integral field spectroscopic observations from the SDSS-IV MaNGA survey to obtain fully spatially-resolved high-resolution star formation historie... Read More about SDSS-IV MaNGA: Excavating the fossil record of stellar populations in spiral galaxies.

Mapping and characterization of cosmic filaments in galaxy cluster outskirts: strategies and forecasts for observations from simulations (2020)
Journal Article
Kuchner, U., Aragón-Salamanca, A., Pearce, F. R., Gray, M. E., Rost, A., Mu, C., …Yepes, G. (2020). Mapping and characterization of cosmic filaments in galaxy cluster outskirts: strategies and forecasts for observations from simulations. Monthly Notices of the Royal Astronomical Society, 494(4), 5473-5491. https://doi.org/10.1093/mnras/staa1083

Upcoming wide-field surveys are well-suited to studying the growth of galaxy clusters by tracing galaxy and gas accretion along cosmic filaments. We use hydrodynamic simulations of volumes surrounding 324 clusters from The ThreeHundred project to dev... Read More about Mapping and characterization of cosmic filaments in galaxy cluster outskirts: strategies and forecasts for observations from simulations.

Identifying Strong Lenses with Unsupervised Machine Learning using Convolutional Autoencoder (2020)
Journal Article
Cheng, T., Li, N., Conselice, C. J., Aragón-Salamanca, A., Dye, S., & Metcalf, R. B. (2020). Identifying Strong Lenses with Unsupervised Machine Learning using Convolutional Autoencoder. Monthly Notices of the Royal Astronomical Society, 394(3), 3750–3765. https://doi.org/10.1093/mnras/staa1015

In this paper we develop a new unsupervised machine learning technique comprised of a feature extractor, a convolutional autoencoder (CAE), and a clustering algorithm consisting of a Bayesian Gaussian mixture model (BGM). We apply this technique to v... Read More about Identifying Strong Lenses with Unsupervised Machine Learning using Convolutional Autoencoder.

Optimizing automatic morphological classification of galaxies with machine learning and deep learning using Dark Energy Survey imaging (2020)
Journal Article
Cheng, T., Conselice, C. J., Aragón-Salamanca, A., Li, N., Bluck, A. F., Hartley, W. G., …Tarle, G. (2020). Optimizing automatic morphological classification of galaxies with machine learning and deep learning using Dark Energy Survey imaging. Monthly Notices of the Royal Astronomical Society, 493(3), 4209-4228. https://doi.org/10.1093/mnras/staa501

There are several supervised machine learning methods used for the application of automated morphological classification of galaxies; however, there has not yet been a clear comparison of these different methods using imaging data, or a investigation... Read More about Optimizing automatic morphological classification of galaxies with machine learning and deep learning using Dark Energy Survey imaging.

Preprocessing among the Infalling Galaxy Population of EDisCS Clusters (2019)
Journal Article
Kirby, M., Just, D. W., Zaritsky, D., Rudnick, G., Desjardins, T., Cool, R., …Liebst, K. (2019). Preprocessing among the Infalling Galaxy Population of EDisCS Clusters. Astrophysical Journal, 885(1), Article 6. https://doi.org/10.3847/1538-4357/ab44a0

We present results from a low-resolution spectroscopic survey for 21 galaxy clusters at 0.4 < z < 0.8 selected from the ESO Distant Cluster Survey. We measured spectra using the low-dispersion prism in IMACS on the Magellan Baade telescope and calcul... Read More about Preprocessing among the Infalling Galaxy Population of EDisCS Clusters.

From the outside looking in: what can Milky Way Analogues tell us about the star formation rate of our own galaxy? (2019)
Journal Article
Fraser-Mckelvie, A., Merrifield, M., & Aragón-Salamanca, A. (2019). From the outside looking in: what can Milky Way Analogues tell us about the star formation rate of our own galaxy?. Monthly Notices of the Royal Astronomical Society, 489(4), 5030–5036. https://doi.org/10.1093/mnras/stz2493

The Milky Way has been described as an anaemic spiral, but is its star formation rate (SFR) unusually low when compared to its peers? To answer this question, we define a sample of Milky Way Analogues (MWAs) based on stringent cuts on the best litera... Read More about From the outside looking in: what can Milky Way Analogues tell us about the star formation rate of our own galaxy?.

Time-slicing spiral galaxies with SDSS-IV MaNGA (2019)
Journal Article
Peterken, T., Fraser-Mckelvie, A., Aragón-Salamanca, A., Merrifield, M., Kraljic, K., Knapen, J. H., …Drory, N. (2019). Time-slicing spiral galaxies with SDSS-IV MaNGA. Monthly Notices of the Royal Astronomical Society, 489(1), 1338–1343. https://doi.org/10.1093/mnras/stz2204/5548799

Spectra of galaxies contain a wealth of information about the stellar populations from which they are made. With integral-field unit (IFU) surveys, such data can be used to map out stellar population properties across the face of a galaxy, allowing o... Read More about Time-slicing spiral galaxies with SDSS-IV MaNGA.

Signatures of stellar accretion in MaNGA early-type galaxies (2019)
Journal Article
Oyarzún, G. A., Bundy, K., Westfall, K. B., Belfiore, F., Thomas, D., Maraston, C., …Andrews, B. H. (2019). Signatures of stellar accretion in MaNGA early-type galaxies. Astrophysical Journal, 880(2), Article 111. https://doi.org/10.3847/1538-4357/ab297c

The late assembly of massive galaxies is thought to be dominated by stellar accretion in their outskirts (beyond 2 effective radii R e) due to dry, minor galaxy mergers. We use observations of 1010 passive early-type galaxies (ETGs) within z < 0.15 f... Read More about Signatures of stellar accretion in MaNGA early-type galaxies.

SDSS-IV MaNGA: Stellar Population Gradients Within Barred Galaxies (2019)
Journal Article
Fraser-McKelvie, A., Merrifield, M., Aragón-Salamanca, A., Peterken, T., Masters, K., Krawczyk, C., …Drory, N. (2019). SDSS-IV MaNGA: Stellar Population Gradients Within Barred Galaxies. Monthly Notices of the Royal Astronomical Society: Letters, 488(1), L6–L11. https://doi.org/10.1093/mnrasl/slz085

Bars in galaxies are thought to stimulate both inflow of material and radial mixing along them. Observational evidence for this mixing has been inconclusive so far however, limiting the evaluation of the impact of bars on galaxy evolution. We now use... Read More about SDSS-IV MaNGA: Stellar Population Gradients Within Barred Galaxies.

The time delay between star formation quenching and morphological transformation of galaxies in clusters: a phase–space view of EDisCS (2019)
Journal Article
Kelkar, K., Gray, M. E., Aragón-Salamanca, A., Rudnick, G., Jaffé, Y. L., Jablonka, P., …Milvang-Jensen, B. (2019). The time delay between star formation quenching and morphological transformation of galaxies in clusters: a phase–space view of EDisCS. Monthly Notices of the Royal Astronomical Society, 486(1), 868-884. https://doi.org/10.1093/mnras/stz905

We explore the possible effect of cluster environments on the structure and star formation histories of galaxies by analysing the projected phase–space (PPS) of intermediate-redshift clusters (0.4 z 0.8). HST I−band imaging data from the ESO Distant... Read More about The time delay between star formation quenching and morphological transformation of galaxies in clusters: a phase–space view of EDisCS.

SDSS IV MaNGA: full spectroscopic bulge-disc decomposition of MaNGA early-type galaxies (2019)
Journal Article
Tabor, M., Merrifield, M., Aragón-Salamanca, A., Fraser-Mckelvie, A., Peterken, T., Smethurst, R., …Lane, R. R. (2019). SDSS IV MaNGA: full spectroscopic bulge-disc decomposition of MaNGA early-type galaxies. Monthly Notices of the Royal Astronomical Society, 485(2), 1546–1558. https://doi.org/10.1093/mnras/stz431

By applying spectroscopic decomposition methods to a sample of MaNGA early-type galaxies, we separate out spatially and kinematically distinct stellar populations, allowing us to explore the similarities and differences between galaxy bulges and disc... Read More about SDSS IV MaNGA: full spectroscopic bulge-disc decomposition of MaNGA early-type galaxies.

The fifteenth data release of the Sloan Digital Sky Surveys: first release of MaNGA derived quantities, data visualization tools and stellar library (2019)
Journal Article
Aguado, D., Ahumada, R., Almeida, A., Anderson, S. F., Andrews, B. H., Anguiano, B., …Zou, H. (2019). The fifteenth data release of the Sloan Digital Sky Surveys: first release of MaNGA derived quantities, data visualization tools and stellar library. Astrophysical Journal Supplement, 240(2), 1-25. https://doi.org/10.3847/1538-4365/aaf651

Twenty years have passed since first light for the Sloan Digital Sky Survey (SDSS). Here, we release data taken by the fourth phase of SDSS (SDSS-IV) across its first three years of operation (2014 July–2017 July). This is the third data release for... Read More about The fifteenth data release of the Sloan Digital Sky Surveys: first release of MaNGA derived quantities, data visualization tools and stellar library.

OMEGA – OSIRIS mapping of emission-line galaxies in A901/2 – V. The rich population of jellyfish galaxies in the multi-cluster system Abell 901/2 (2019)
Journal Article
Roman-Oliveira, F. V., Chies-Santos, A. L., Rodríguez Del Pino, B., Aragón-Salamanca, A., Gray, M. E., & Bamford, S. P. (2019). OMEGA – OSIRIS mapping of emission-line galaxies in A901/2 – V. The rich population of jellyfish galaxies in the multi-cluster system Abell 901/2. Monthly Notices of the Royal Astronomical Society, 484(1), 892–905. https://doi.org/10.1093/mnras/stz007

We present the results of a systematic search and characterisation of galaxies with morphological signatures of ram-pressure stripping, known as jellyfish galaxies, in the multi-cluster system A901/2, at z ∼ 0.165, as part of the OMEGA survey. By vis... Read More about OMEGA – OSIRIS mapping of emission-line galaxies in A901/2 – V. The rich population of jellyfish galaxies in the multi-cluster system Abell 901/2.

Tidal interactions and mergers in intermediate redshift EDisCS clusters (2018)
Journal Article
Deger, S., Rudnick, G., Kelkar, K., Aragón-Salamanca, A., Desai, V., Lotz, J. M., …Zaritsky, D. (2018). Tidal interactions and mergers in intermediate redshift EDisCS clusters. Astrophysical Journal, 869(1), Article 6. https://doi.org/10.3847/1538-4357/aaeb87

We study the fraction of tidal interactions and mergers with well identified observability timescales (fTIM) in group, cluster, and accompanying field galaxies and its dependence on redshift (z), cluster velocity dispersion (sigma) and environment an... Read More about Tidal interactions and mergers in intermediate redshift EDisCS clusters.

A direct test of density wave theory in a grand-design spiral galaxy (2018)
Journal Article
Peterken, T. G., Merrifield, M. R., Aragón-Salamanca, A., Drory, N., Krawczyk, C. M., Masters, K. L., …Westfall, K. B. (2019). A direct test of density wave theory in a grand-design spiral galaxy. Nature Astronomy, 3(2), 178-182. https://doi.org/10.1038/s41550-018-0627-5

The exact nature of the arms of spiral galaxies is still an open question1. It has been widely assumed that spiral arms in galaxies with two distinct symmetrical arms are the products of density waves that propagate around the disk, with the spiral a... Read More about A direct test of density wave theory in a grand-design spiral galaxy.

SDSS-IV MaNGA: the formation sequence of S0 galaxies (2018)
Journal Article
Fraser-McKelvie, A., Aragon-Salamanca, A., Merrifield, M., Tabor, M., Bernardi, M., Drory, N., …Argudo-Fernandez, M. (2018). SDSS-IV MaNGA: the formation sequence of S0 galaxies. Monthly Notices of the Royal Astronomical Society, 481(4), 5580-5591. https://doi.org/10.1093/mnras/sty2563

Gas stripping of spiral galaxies or mergers are thought to be the formation mechanisms of lenticular galaxies. In order to determine the conditions in which each scenario dominates, we derive stellar populations of both the bulge and disk regions of... Read More about SDSS-IV MaNGA: the formation sequence of S0 galaxies.

OMEGA-OSIRIS mapping of emission-line galaxies in A901/2:IV: extinction of star-formation estimators with inclination (2018)
Journal Article
Wolf, C., Weinzirl, T., Aragón-Salamanca, A., Gray, M. E., Rodríguez del Pino, B., Chies-Santos, A. L., …Harborne, K. (2018). OMEGA-OSIRIS mapping of emission-line galaxies in A901/2:IV: extinction of star-formation estimators with inclination. Monthly Notices of the Royal Astronomical Society, 480(3), 3788–3799. https://doi.org/10.1093/mnras/sty2112

We study the effect of inclination on the apparent brightness of star-forming galaxies in spectral passbands that are commonly used as star-formation indicators. As diagnostics we use mass-to-light ratios in three passbands: the UV continuum at 280 n... Read More about OMEGA-OSIRIS mapping of emission-line galaxies in A901/2:IV: extinction of star-formation estimators with inclination.

Spectroscopic decomposition of the galaxy and halo of the cD galaxy NGC 3311 (2018)
Journal Article
Johnston, E. J., Merrifield, M., & Aragón-Salamanca, A. (in press). Spectroscopic decomposition of the galaxy and halo of the cD galaxy NGC 3311. Monthly Notices of the Royal Astronomical Society, 478(3), https://doi.org/10.1093/mnras/sty1342

Information on the star-formation histories of cD galaxies and their extended stellar haloes lie in their spectra. Therefore, to determine whether these structures evolved together or through a two-phase formation, we need to spectroscopically separa... Read More about Spectroscopic decomposition of the galaxy and halo of the cD galaxy NGC 3311.

The fourteenth data release of the Sloan Digital Sky Survey: first spectroscopic data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment (2018)
Journal Article
Abolfathi, B., Aguado, D., Aguilar, G., Allende Prieto, C., Almeida, A., Ananna, T. T., …Smethurst, R. J. (in press). The fourteenth data release of the Sloan Digital Sky Survey: first spectroscopic data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment. Astrophysical Journal Supplement, 235(2), https://doi.org/10.3847/1538-4365/aa9e8a

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). Th... Read More about The fourteenth data release of the Sloan Digital Sky Survey: first spectroscopic data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment.

SDSS-IV MaNGA: uncovering the angular momentum content of central and satellite early-type galaxies (2018)
Journal Article
Greene, J., Leauthaud, A., Emsellem, E., Ge, J., Aragón-Salamanca, A., Greco, J., …van den Bosch, F. (2018). SDSS-IV MaNGA: uncovering the angular momentum content of central and satellite early-type galaxies. Astrophysical Journal, 852(1), Article 36. https://doi.org/10.3847/1538-4357/aa9bde

We study 379 central and 159 satellite early-type galaxies with two-dimensional kinematics from the integral field survey Mapping Nearby Galaxies at APO (MaNGA) to determine how their angular momentum content depends on stellar and halo mass. Using t... Read More about SDSS-IV MaNGA: uncovering the angular momentum content of central and satellite early-type galaxies.

The 13th data release of the Sloan Digital Sky Survey: first spectroscopic data from the SDSS-IV survey mapping nearby galaxies at Apache Point Observatory (2017)
Journal Article
Albareti, F. D., Prieto, C. A., Almeida, A., Anders, F., Anderson, S., Andrews, B. H., …and 125 authors. (2017). The 13th data release of the Sloan Digital Sky Survey: first spectroscopic data from the SDSS-IV survey mapping nearby galaxies at Apache Point Observatory. Astrophysical Journal Supplement, 233(2), https://doi.org/10.3847/1538-4365/aa8992

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in 2014 July. It pursues three core programs: the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2), Mapping Nearby Galaxies at APO (MaNGA), and the... Read More about The 13th data release of the Sloan Digital Sky Survey: first spectroscopic data from the SDSS-IV survey mapping nearby galaxies at Apache Point Observatory.

Determining the halo mass scale where galaxies lose their gas (2017)
Journal Article
Rudnick, G., Jablonka, P., Moustakas, J., Aragón-Salamanca, A., Zaritsky, D., Jaffe, Y. L., …Poggianti, B. (2017). Determining the halo mass scale where galaxies lose their gas. Astrophysical Journal, 850(2), Article 181. https://doi.org/10.3847/1538-4357/aa866c

A major question in galaxy formation is how the gas supply that fuels activity in galaxies is modulated by their environment. We use spectroscopy of a set of well characterized clusters and groups at $0.45$\AA\ is $f_{[OII]}=0.08^{+0.03}_{-0.02}$ and... Read More about Determining the halo mass scale where galaxies lose their gas.

SDSS-IV MaNGA: the different quenching histories of fast and slow rotators (2017)
Journal Article
Smethurst, R. J., Masters, K. L., Lintott, C. J., Weijmans, A., Merrifield, M. R., Penny, S. J., …Nichol, R. C. (2018). SDSS-IV MaNGA: the different quenching histories of fast and slow rotators. Monthly Notices of the Royal Astronomical Society, 473(2), 2679-2687. https://doi.org/10.1093/mnras/stx2547

Do the theorised different formation mechanisms of fast and slow rotators produce an observable difference in their star formation histories? To study this we identify quenching slow rotators in the MaNGA sample by selecting those which lie below the... Read More about SDSS-IV MaNGA: the different quenching histories of fast and slow rotators.

Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe (2017)
Journal Article
Blanton, M. R., Bershady, M. A., Abolfathi, B., Albareti, F. D., Prieto, C. A., Almeida, A., …Zou, H. (2017). Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe. Astronomical Journal, 154(1), 1-35. https://doi.org/10.3847/1538-3881/aa7567

We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high re... Read More about Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe.

OMEGA - OSIRIS mapping of emission-line galaxies in A901/2: III. - Galaxy properties across projected phase space in A901/2 (2017)
Journal Article
Weinzirl, T., Aragón-Salamanca, A., Gray, M. E., Bamford, S. P., Rodriguez Del Pino, B., Chies-Santos, A. L., …Cool, R. J. (2017). OMEGA - OSIRIS mapping of emission-line galaxies in A901/2: III. - Galaxy properties across projected phase space in A901/2. Monthly Notices of the Royal Astronomical Society, 471(1), 182-200. https://doi.org/10.1093/mnras/stx1525

We conduct a comprehensive projected phase-space analysis of the A901/2 multicluster system at z ∼ 0.165. Aggregating redshifts from spectroscopy, tunable-filter imaging and prism techniques, we assemble a sample of 856 cluster galaxies reaching 108.... Read More about OMEGA - OSIRIS mapping of emission-line galaxies in A901/2: III. - Galaxy properties across projected phase space in A901/2.

The effect of the environment on the structure, morphology and star-formation history of intermediate-redshift galaxies (2017)
Journal Article
Kelkar, K., Gray, M. E., Aragón-Salamanca, A., Rudnick, G., Milvang-Jensen, B., Jablonka, P., & Schrabback, T. (2017). The effect of the environment on the structure, morphology and star-formation history of intermediate-redshift galaxies. Monthly Notices of the Royal Astronomical Society, 469(4), 4551-4564. https://doi.org/10.1093/mnras/stx1155

With the aim of understanding the effect of the environment on the star formation history and morphological transformation of galaxies, we present a detailed analysis of the colour, morphology and internal structure of cluster and field galaxies at 0... Read More about The effect of the environment on the structure, morphology and star-formation history of intermediate-redshift galaxies.

SDSS-IV MaNGA IFS galaxy survey—survey design, execution, and initial data quality (2016)
Journal Article
Yan, R., Bundy, K., Law, D. R., Bershady, M. A., Andrews, B., Cherinka, B., …Zheng, Z. (2016). SDSS-IV MaNGA IFS galaxy survey—survey design, execution, and initial data quality. Astronomical Journal, 152(6), Article 197. https://doi.org/10.3847/0004-6256/152/6/197

The MaNGA Survey (Mapping Nearby Galaxies at Apache Point Observatory) is one of three core programs in the Sloan Digital Sky Survey IV. It is obtaining integral field spectroscopy for 10,000 nearby galaxies at a spectral resolution of R ∼ 2000 from... Read More about SDSS-IV MaNGA IFS galaxy survey—survey design, execution, and initial data quality.

The demographics of galactic bulges in the SDSS database (2016)
Journal Article
Kim, K., Oh, S., Jeong, H., Aragón-Salamanca, A., Smith, R., & Yi, S. K. (2016). The demographics of galactic bulges in the SDSS database. Astrophysical Journal Supplement, 225(1), Article 6. https://doi.org/10.3847/0067-0049/225/1/6

We present a new database of our two-dimensional bulge–disk decompositions for 14,233 galaxies drawn from Sloan Digital Sky Survey DR12 in order to examine the properties of bulges residing in the local universe (0.005 < z < 0.05). We performed decom... Read More about The demographics of galactic bulges in the SDSS database.

Wavelength self-calibration and sky subtraction for Fabry–Pérot interferometers: applications to OSIRIS (2015)
Journal Article
Weinzirl, T., Aragón-Salamanca, A., Bamford, S., Rodríguez del Pino, B., Gray, M., & Chies-Santos, A. (2015). Wavelength self-calibration and sky subtraction for Fabry–Pérot interferometers: applications to OSIRIS. Monthly Notices of the Royal Astronomical Society, 454(2), https://doi.org/10.1093/mnras/stv2230

We describe techniques concerning wavelength calibration and sky subtraction to maximize the scientific utility of data from tunable filter instruments. While we specifically address data from the Optical System for Imaging and low Resolution Integra... Read More about Wavelength self-calibration and sky subtraction for Fabry–Pérot interferometers: applications to OSIRIS.

OMEGA - OSIRIS Mapping of Emission-line Galaxies in A901/2: I. Survey description, data analysis, and star formation and AGN activity in the highest density regions (2015)
Journal Article
Chies-Santos, A., Rodriguez del Pino, B., Aragón-Salamanca, A., Bamford, S., Gray, M., Wolf, C., …Weinzirl, T. (2015). OMEGA - OSIRIS Mapping of Emission-line Galaxies in A901/2: I. Survey description, data analysis, and star formation and AGN activity in the highest density regions. Monthly Notices of the Royal Astronomical Society, 450(4), 4458-4474. https://doi.org/10.1093/mnras/stv779

We present an overview of and first results from the OMEGA (OSIRIS Mapping of Emission-line Galaxies in the multicluster system A901/2) survey. The ultimate goal of this project is to study star formation and active galactic nucleus (AGN) activity ac... Read More about OMEGA - OSIRIS Mapping of Emission-line Galaxies in A901/2: I. Survey description, data analysis, and star formation and AGN activity in the highest density regions.

GLACE survey: OSIRIS/GTC tuneable filter H? imaging of the rich galaxy cluster ZwCl 0024.0+1652 at z=0.395 (2015)
Journal Article
Sánchez-Portal, M., Pintos-Castro, I., Pérez-Martínez, R., Cepa,, J., Pérez García, A., Domínguez-Sánchez, H., …Valtchanov, I. (2015). GLACE survey: OSIRIS/GTC tuneable filter Hα imaging of the rich galaxy cluster ZwCl 0024.0+1652 at z=0.395. Astronomy and Astrophysics, 578, Article A30. https://doi.org/10.1051/0004-6361/201525620

The cores of clusters at 0 ≲ z ≲ 1 are dominated by quiescent early-type galaxies, whereas the field is dominated by star-forming late-type galaxies. Clusters grow through the accretion of galaxies and groups from the surrounding field, which implies... Read More about GLACE survey: OSIRIS/GTC tuneable filter H? imaging of the rich galaxy cluster ZwCl 0024.0+1652 at z=0.395.

Galaxy sizes as a function of environment at intermediate redshift from the ESO Distant Cluster Survey (2015)
Journal Article
Kelkar, K., Aragón-Salamanca, A., Gray, M., Maltby, D., Vulcani, B., De Lucia, G., …Zaritsky, D. (2015). Galaxy sizes as a function of environment at intermediate redshift from the ESO Distant Cluster Survey. Monthly Notices of the Royal Astronomical Society, 450(2), https://doi.org/10.1093/mnras/stv670

In order to assess whether the environment has a significant effect on galaxy sizes, we compare the mass–size relations of cluster and field galaxies in the 0.4

The environmental dependence of the structure of galactic discs in STAGES S0 galaxies: implications for S0 formation (2015)
Journal Article
Maltby, D. T., Aragón-Salamanca, A., Gray, M. E., Hoyos, C., Wolf, C., Jogee, S., & Böhm, A. (in press). The environmental dependence of the structure of galactic discs in STAGES S0 galaxies: implications for S0 formation. Monthly Notices of the Royal Astronomical Society, 447(2), https://doi.org/10.1093/mnras/stu2536

We present an analysis of V-band radial surface brightness ?(r) profiles for S0 galaxies in different environments using Hubble Space Telescope/Advanced Camera for Surveys imaging and data from the Space Telescope A901/2 Galaxy Evolution Survey. Usin... Read More about The environmental dependence of the structure of galactic discs in STAGES S0 galaxies: implications for S0 formation.

Overview of the SDSS-IV MaNGA survey: mapping nearby galaxies at Apache Point Observatory (2014)
Journal Article
Bundy, K., Bershady, M. A., Law, D. R., Yan, R., Drory, N., MacDonald, N., …Zhang, K. (2014). Overview of the SDSS-IV MaNGA survey: mapping nearby galaxies at Apache Point Observatory. Astrophysical Journal, 798(1), 7. https://doi.org/10.1088/0004-637x/798/1/7

We present an overview of a new integral field spectroscopic survey called MaNGA (Mapping Nearby Galaxies at Apache Point Observatory), one of three core programs in the fourth-generation Sloan Digital Sky Survey (SDSS-IV) that began on 2014 July 1.... Read More about Overview of the SDSS-IV MaNGA survey: mapping nearby galaxies at Apache Point Observatory.

Herschel-ATLAS: properties of dusty massive galaxies at low and high redshifts (2014)
Journal Article
Rowlands, K., Dunne, L., Dye, S., Aragón-Salamanca, A., Maddox, S., da Cunha, E., …Valiante, E. (2014). Herschel-ATLAS: properties of dusty massive galaxies at low and high redshifts. Monthly Notices of the Royal Astronomical Society, 441(2), https://doi.org/10.1093/mnras/stu510

We present a comparison of the physical properties of a rest-frame 250-μm-selected sample of massive, dusty galaxies from 0 < z < 5.3. Our sample comprises 29 high-redshift submillimetre galaxies (SMGs) from the literature and 843 dusty galaxies at z... Read More about Herschel-ATLAS: properties of dusty massive galaxies at low and high redshifts.

The dust budget crisis in high-redshift submillimetre galaxies (2014)
Journal Article
Rowlands, K., Gomez, H., Dunne, L., Aragón-Salamanca, A., Dye, S., Maddox, S., …van der Werf, P. (in press). The dust budget crisis in high-redshift submillimetre galaxies. Monthly Notices of the Royal Astronomical Society, 441(2), https://doi.org/10.1093/mnras/stu605

We apply a chemical evolution model to investigate the sources and evolution of dust in a sample of 26 high-redshift (z > 1) submillimetre galaxies (SMGs) from the literature, with complete photometry from ultraviolet to the submillimetre. We show th... Read More about The dust budget crisis in high-redshift submillimetre galaxies.

Ionized gas discs in elliptical and S0 galaxies at z < 1 (2014)
Journal Article
Jaffe, Y. L., Aragón-Salamanca, A., Ziegler, B., Kuntschner, H., Zaritsky, D., Rudnick, G., …Demarco, R. (2014). Ionized gas discs in elliptical and S0 galaxies at z < 1. Monthly Notices of the Royal Astronomical Society, 440(4), https://doi.org/10.1093/mnras/stu507

We analyse the extended, ionized-gas emission of 24 early-type galaxies (ETGs) at 0 < z < 1 from the ESO Distant Cluster Survey (EDisCS). We discuss different possible sources of ionization and favour star formation as the main cause of the observed... Read More about Ionized gas discs in elliptical and S0 galaxies at z < 1.