External Galaxies | Open Access Articles | Digital Commons Network™

Using 4most To Refine The Measurement Of Galaxy Properties: A Case Study Of Supernova Hosts, J Dumayne, I M. Hook, S C. Williams, G A. Lowes, D Head, A Fritz, O Graur, Benne Holwerda, A Humphrey, A Milligan, M Nicholl, B F. Roukema, P Wiseman

Faculty Scholarship

The Rubin Observatory’s 10-year Legacy Survey of Space and Time will observe near to 20 billion galaxies. For each galaxy the properties can be inferred. Approximately 105 galaxies observed per year will contain Type Ia supernovae (SNe), allowing SN host-galaxy properties to be calculated on a large scale. Measuring the properties of SN host-galaxies serves two main purposes. The first is that there are known correlations between host-galaxy type and supernova type, which can be used to aid in the classification of SNe. Secondly, Type Ia SNe exhibit correlations between host-galaxy properties and the peak luminosities of the SNe, which …

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The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology, Lori E. Porter, Benne Holwerda, Sandor Kruk, Maritza Lara-López, Kevin A. Pimbblet, Christopher P A Henry, Sarah Casura, Lee S. Kelvin

Faculty Scholarship

The large-scale structure of the Universe is comprised of galaxy filaments, tendrils, and voids. The majority of the Universe’s volume is taken up by these voids, which exist as underdense, but not empty, regions. The galaxies found inside these voids are expected to be some of the most isolated objects in the Universe. This study, using the Galaxy and Mass Assembly (GAMA) and Galaxy Zoo surveys, aims to investigate basic physical properties and morphology of void galaxies versus field (filament and tendril) galaxies. We use void galaxies with stellar masses (⁠M∗" role="presentation" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; …

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Gama/Devils: Cosmic Star Formation And Agn Activity Over 12.5 Billion Years, Jordan C J D’Silva, Simon P. Driver, Claudia D P Lagos, Aaron S G Robotham, Sabine Bellstedt, Luke J M Davies, Jessica E. Thorne, Joss Bland-Hawthorn, Matias Bravo, Benne Holwerda, Steven Phillipps, Nick Seymour, Malgorzata Siudek, Rogier A. Windhorst

Faculty Scholarship

We use the Galaxy and Mass Assembly (GAMA) and the Deep Extragalactic Visible Legacy Survey (DEVILS) observational data sets to calculate the cosmic star formation rate (SFR) and active galactic nuclei (AGN) bolometric luminosity history (CSFH/CAGNH) over the last 12.5 billion years. SFRs and AGN bolometric luminosities were derived using the spectral energy distribution fitting code ProSpect, which includes an AGN prescription to self consistently model the contribution from both AGN and stellar emission to the observed rest-frame ultra-violet to far-infrared photometry. We find that both the CSFH and CAGNH evolve similarly, rising in the early Universe up to a …

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Galaxy And Mass Assembly (Gama): Comparing Visually And Spectroscopically Identified Galaxy Merger Samples, Alice Desmons, Sarah Brough, Cristina Martínez-Lombilla, Roberto De Propris, Benne Holwerda, Ángel R. López-Sánchez

Faculty Scholarship

We conduct a comparison of the merging galaxy populations detected by a sample of visual identification of tidal features around galaxies as well as spectroscopically detected close pairs of galaxies to determine whether our method of selecting merging galaxies biases our understanding of galaxy interactions. Our volume-limited parent sample consists of 852 galaxies from the Galaxy And Mass Assembly (GAMA) survey in the redshift range 0.04 ≤ z ≤ 0.20 and stellar mass range 9.50 ≤ log 10(M⋆/M⊙)≤ 11.0" role="presentation" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-variant: inherit; font-stretch: inherit; line-height: normal; font-family: inherit; font-optical-sizing: inherit; font-kerning: inherit; …

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Red Riding On Hood: Exploring How Galaxy Colour Depends On Environment, Pankaj C. Bhambhani, Ivan K. Baldry, Sarah Brough, Alexander D. Hill, M A. Lara-Lopez, J Loveday, Benne Holwerda

Faculty Scholarship

Galaxy populations are known to exhibit a strong colour bimodality, corresponding to blue star-forming and red quiescent subpopulations. The relative abundance of the two populations has been found to vary with stellar mass and environment. In this paper, we explore the effect of environment considering different types of measurements. We choose a sample of 49 911 galaxies with 0.05 < z < 0.18 from the Galaxy And Mass Assembly survey. We study the dependence of the fraction of red galaxies on different measures of the local environment as well as the large-scale `geometric’ environment defined by density gradients in the surrounding cosmic web. We find that the red galaxy fraction varies with the environment at fixed stellar mass. The red fraction depends more strongly on local environmental measures than on large-scale geometric environment measures. By comparing the different environmental densities, we show that no density measurement fully explains the observed environmental red fraction variation, suggesting the different measures of environmental density contain different information. We test whether the local environmental measures, when combined together, can explain all the observed environmental red fraction variation. The geometric environment has a small residual effect, and this effect is larger for voids than any other type of geometric environment. This could provide a test of the physics applied to cosmological-scale galaxy evolution simulations as it combines large-scale effects with local environmental impact.

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The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology., Lori E. Porter

College of Arts & Sciences Senior Honors Theses

The large-scale structure (LSS) of the Universe is comprised of galaxy filaments, tendrils, and voids. The majority of the Universe’s volume is taken up by these voids, which exist as underdense, but not empty, regions. The galaxies found inside voids are void galaxies and expected to be some of the most isolated objects in the Universe. However, their standard morphology remains poorly studied. This study, using the Galaxy and Mass Assembly (GAMA) data and Galaxy Zoo survey, aims to remedy this. For completeness purposes, we use void galaxies identified by Alpaslan et al. (2014) with stellar masses (M*) of 10 …

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Galaxy And Mass Assembly (Gama): Low-Redshift Quasars And Inactive Galaxies Have Similar Neighbors, Maria B. Stone, Clare F. Wethers, Roberto De Propris, Jari Kotilainen, Nischal Acharya, Benne W. Holwerda, Jonathan Loveday, Steven Phillipps

Faculty Scholarship

We explore the properties of galaxies in the proximity (within a ∼2 Mpc radius sphere) of Type I quasars at 0.1 <z <0.35, to check whether and how an active galaxy influences the properties of its neighbors. We further compare these with the properties of neighbors around inactive galaxies of the same mass and redshift within the same volume of space, using the Galaxy and Mass Assembly spectroscopic survey. Our observations reveal no significant difference in properties such as the number of neighbors, morphologies, stellar mass, star formation rates, and star formation history between the neighbors of quasars and those of the comparison sample. This implies that quasar activity in a host galaxy does not significantly affect its neighbors (e.g., via interactions with the jets). Our results suggest that quasar host galaxies do not strongly differ from the average galaxy within the specified mass and redshift range. Additionally, the implication of the relatively minor importance of the environmental effect on and from quasars is that nuclear activity is more likely triggered by internal and secular processes.

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Jwst’S Pearls: Dust Attenuation And Gravitational Lensing In The Backlit-Galaxy System Vv 191, William C. Keel, Rogier A. Windhorst, Rolf A. Jansen, Seth H. Cohen, Jake Summers, Benne Holwerda, Sarah T. Bradford, Clayton D. Robertson, Giovanni Ferrami, Stuart Wyithe, Haojing Yan, Christopher J. Conselice, Simon P. Driver, Aaron Robotham, Norman A. Grogin, Christopher N. A. Willmer, Anton M. Koekemoer, Brenda L. Frye, Nimish P. Hathi, Russell E. Ryan Jr., Nor Pirzkal, Madeline A. Marshall, Dan Coe, Jose M. Diego, Thomas J. Broadhurst, Michael J. Rutkowski, Lifan Wang, S. P. Willner, Andreea Petric, Cheng Cheng, Adi Zitrin

Faculty Scholarship

We present the first JWST observations of the z = 4.11 luminous radio galaxy TN J1338–1942, obtained as part of the ‘Prime Extragalactic Areas for Reionization and Lensing Science’ (‘PEARLS’) project. Our NIRCam observations, designed to probe the key rest-frame optical continuum and emission line features at this redshift, enable resolved spectral energy distribution modelling that incorporates both a range of stellar population assumptions and radiative shock models. With an estimated stellar mass of log10(M/M⊙) ∼ 10.9, TN J1338–1942 is confirmed to be one of the most massive galaxies known at this epoch. Our observations also reveal extremely high equivalent-width …

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Wallaby Pilot Survey: Hydra Cluster Galaxies Uv And H I Morphometrics, Benne W. Holwerda, Frank Bigiel, Albert Bosma, Helene M. Courtois, Nathan Deg, Helga Dénes, Ahmed Elagali, Bi-Qing For, Baerbel Koribalski, Denis A. Leahy, Karen Lee-Waddell, Ángel R. López-Sánchez, Se-Heon Oh, Tristan N. Reynolds, Jonghwan Rhee, Kristine Spekkens, Jing Wang, Tobias Westmeier, O Ivy Wong

Faculty Scholarship

Galaxy morphology in atomic hydrogen (H I) and in the ultraviolet (UV) are closely linked. This has motivated their combined use to quantify morphology over the full H I disc for both H I and UV imaging. We apply galaxy morphometrics: concentration, asymmetry, gini, M₂₀ and multimode-intensity-deviation statistics to the first moment-0 maps of the WALLABY Survey of galaxies in the hydra cluster centre. Taking advantage of this new H I survey, we apply the same morphometrics over the full H I extent on archival GALEX FUV and NUV data to explore how well H I truncated, extended ultraviolet …

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Modelling Strong Lenses From Wide-Field Ground-Based Observations In Kids And Gama, Shawn Knabel, Benne Holwerda, J Nightingale, T Treu, M Bilicki, S Brough, S Driver, L Finnerty, L Haberzettl, S Hegde, A M. Hopkins, K Kuijken, J Liske, A K. Pimblett, R C. Steele, A H. Wright

Faculty Scholarship

Despite the success of galaxy-scale strong gravitational lens studies with Hubble-quality imaging, a number of well-studied strong lenses remains small. As a result, robust comparisons of the lens models to theoretical predictions are difficult. This motivates our application of automated Bayesian lens modelling methods to observations from public data releases of overlapping large ground-based imaging and spectroscopic surveys: Kilo-Degree Survey (KiDS) and Galaxy and Mass Assembly (GAMA), respectively. We use the open-source lens modelling software PYAUTOLENS to perform our analysis. We demonstrate the feasibility of strong lens modelling with large-survey data at lower resolution as a complementary avenue to studies …

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Clear: Spatially Resolved Emission Lines And Active Galactic Nuclei At 0.6 < Z < 1.3, Bren E. Backhaus, Joanna S. Bridge, Jonathan R. Trump, Nikko J. Cleri, Casey Papovich, Raymond C. Simons, Ivelina Momcheva, Benne Holwerda, Zhiyuan Ji, Intae Jung, Jasleen Matharu

Faculty Scholarship

We investigate spatially resolved emission-line ratios in a sample of 219 galaxies (0.6 < z < 1.3) detected using the G102 grism on the Hubble Space Telescope Wide Field Camera 3 taken as part of the CANDELS Lyα Emission at Reionization survey to measure ionization profiles and search for low-luminosity active galactic nuclei (AGN). We analyze [O III] and Hβ emission-line maps, enabling us to spatially resolve the [O III]/Hβ emission-line ratio across the galaxies in the sample. We compare the [O III]/Hβ ratio in galaxy centers and outer annular regions to measure ionization differences and investigate the potential of sources with nuclear ionization to host AGN. We investigate some of the individual galaxies that are candidates to host strong nuclear ionization and find that they often have low stellar mass and are undetected in X-rays, as expected for low-luminosity AGN in low-mass galaxies. We do not find evidence for a significant population of off-nuclear AGN or other clumps of off-nuclear ionization. We model the observed distribution of [O III]/Hβ spatial profiles and find that most galaxies are consistent with a small or zero difference between their nuclear and off-nuclear line ratios, but 6%–16% of galaxies in the sample are likely to host nuclear [O III]/Hβ that is ∼0.5 dex higher than in their outer regions. This study is limited by large uncertainties in most of the measured [O III]/Hβ spatial profiles; therefore, deeper data, e.g., from deeper HST/ WFC3 programs or from JWST/NIRISS, are needed to more reliably measure the spatially resolved emission-line conditions of individual high-redshift galaxies.

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The Loneliest Galaxies In The Universe: A Gama And Galaxyzoo Study On Void Galaxy Morphology, Lori E. Porter, Benne W. Holwerda

The Cardinal Edge

The large-scale structure (LSS) of the universe is comprised of galaxy filaments, tendrils, and voids. The majority of the universe’s volume is taken up by these voids, which exist as underdense, but not empty, regions. The galaxies found inside voids are void galaxies and expected to be some of the most isolated objects in the universe. However, their standard morphology remains poorly studied. This study, using the Galaxy and Mass Assembly (GAMA) survey and Galaxy Zoo’s SDSS survey, aims to remedy this. To do so, survey results from GAMA have been plotted using the Sérsic index (n) to analyze morphology, …

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Gama/H-Atlas : Common Star Formation Rate Indicators And Their Dependence On Galaxy Physical Parameters., L. Wang, P. Norberg, M. L. P. Gunawardhana, S. Heinis, I. K. Baldry, J. Bland-Hawthorn, N. Bourne, S. Brough, M. J. I. Brown, M. E. Cluver, A. Cooray, E. Da Cunha, S. P. Driver, L. Dunne, S. Dye, S. Eales, M. W. Grootes, Benne W. Holwerda, A. M. Hopkins, E. Ibar, R. Ivison, C. Lacey, M. A. Lara-Lopez, J. Loveday, S. J. Maddox, M. J. Michalowski, I. Oteo, M. S. Owers, C. C. Popescu, D. J. B. Smith, E. N. Taylor, R. J. Tuffs, P. Van Der Werf

Faculty Scholarship

We compare common star formation rate (SFR) indicators in the local Universe in the Galaxy and Mass Assembly (GAMA) equatorial fields (∼160 deg2), using ultraviolet (UV) photometry from GALEX, far-infrared and sub-millimetre (sub-mm) photometry from Herschel Astrophysical Terahertz Large Area Survey, and Hα spectroscopy from the GAMA survey. With a high-quality sample of 745 galaxies (median redshift z = 0.08), we consider three SFR tracers: UV luminosity corrected for dust attenuation using the UV spectral slope β (SFRUV, corr), Hα line luminosity corrected for dust using the Balmer decrement (BD) (SFRH α, corr), and the combination of UV and infrared …

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External Galaxies Commons^™

Full-Text Articles in External Galaxies

Using 4most To Refine The Measurement Of Galaxy Properties: A Case Study Of Supernova Hosts, J Dumayne, I M. Hook, S C. Williams, G A. Lowes, D Head, A Fritz, O Graur, Benne Holwerda, A Humphrey, A Milligan, M Nicholl, B F. Roukema, P Wiseman

Faculty Scholarship

The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology, Lori E. Porter, Benne Holwerda, Sandor Kruk, Maritza Lara-López, Kevin A. Pimbblet, Christopher P A Henry, Sarah Casura, Lee S. Kelvin

Faculty Scholarship

Faculty Scholarship

Galaxy And Mass Assembly (Gama): Comparing Visually And Spectroscopically Identified Galaxy Merger Samples, Alice Desmons, Sarah Brough, Cristina Martínez-Lombilla, Roberto De Propris, Benne Holwerda, Ángel R. López-Sánchez

Faculty Scholarship

Red Riding On Hood: Exploring How Galaxy Colour Depends On Environment, Pankaj C. Bhambhani, Ivan K. Baldry, Sarah Brough, Alexander D. Hill, M A. Lara-Lopez, J Loveday, Benne Holwerda

Faculty Scholarship

The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology., Lori E. Porter

College of Arts & Sciences Senior Honors Theses

Galaxy And Mass Assembly (Gama): Low-Redshift Quasars And Inactive Galaxies Have Similar Neighbors, Maria B. Stone, Clare F. Wethers, Roberto De Propris, Jari Kotilainen, Nischal Acharya, Benne W. Holwerda, Jonathan Loveday, Steven Phillipps

Faculty Scholarship

Faculty Scholarship

Faculty Scholarship

Modelling Strong Lenses From Wide-Field Ground-Based Observations In Kids And Gama, Shawn Knabel, Benne Holwerda, J Nightingale, T Treu, M Bilicki, S Brough, S Driver, L Finnerty, L Haberzettl, S Hegde, A M. Hopkins, K Kuijken, J Liske, A K. Pimblett, R C. Steele, A H. Wright

Faculty Scholarship

Clear: Spatially Resolved Emission Lines And Active Galactic Nuclei At 0.6 < Z < 1.3, Bren E. Backhaus, Joanna S. Bridge, Jonathan R. Trump, Nikko J. Cleri, Casey Papovich, Raymond C. Simons, Ivelina Momcheva, Benne Holwerda, Zhiyuan Ji, Intae Jung, Jasleen Matharu

Faculty Scholarship

The Loneliest Galaxies In The Universe: A Gama And Galaxyzoo Study On Void Galaxy Morphology, Lori E. Porter, Benne W. Holwerda

The Cardinal Edge

Faculty Scholarship