Physical Sciences and Mathematics Commons^™

Inside-Out Growth Or Inside-Out Quenching? Clues From Colour Gradients Of Local Galaxies, Jianhui Lian, Renbin Yan, Michael Blanton, Xu Kong

Physics and Astronomy Faculty Publications

We constrain the spatial gradient of star formation history (SFH) within galaxies using the colour gradients in NUV − u (where NUV stands for near-ultraviolet) and u − i for a local spatially resolved galaxy sample. By splitting each galaxy into an inner and an outer part, we find that most galaxies show negative gradients in these two colours. We first rule out dust extinction gradient and metallicity gradient as the dominant source for the colour gradient. Then using stellar population models, we explore variations in SFH to explain the colour gradients. As shown by our earlier work, a two-phase …

The Sdss-Iv Manga Sample: Design, Optimization, And Usage Considerations, David A. Wake, Kevin Bundy, Aleksandar M. Diamond-Stanic, Renbin Yan, Michael R. Blanton, Matthew A. Bershady, José R. Sánchez-Gallego, Niv Drory, Amy Jones, Guinevere Kauffmann, David R. Law, Cheng Li, Nicholas Macdonald, Karen Masters, Daniel Thomas, Jeremy Tinker, Anne-Marie Weijmans, Joel R. Brownstein

Physics and Astronomy Faculty Publications

We describe the sample design for the SDSS-IV MaNGA survey and present the final properties of the main samples along with important considerations for using these samples for science. Our target selection criteria were developed while simultaneously optimizing the size distribution of the MaNGA integral field units (IFUs), the IFU allocation strategy, and the target density to produce a survey defined in terms of maximizing signal-to-noise ratio, spatial resolution, and sample size. Our selection strategy makes use of redshift limits that only depend on i-band absolute magnitude (M_i ), or, for a small subset of our sample, …

A Local Leaky-Box Model For The Local Stellar Surface Density-Gas Surface Density-Gas Phase Metallicity Relation, Guangtun Ben Zhu, Jorge K. Barrera-Ballesteros, Timothy M. Heckman, Nadia L. Zakamska, Sebastian F. Sánchez, Renbin Yan, Jonathan Brinkman

Physics and Astronomy Faculty Publications

We revisit the relation between the stellar surface density, the gas surface density and the gas-phase metallicity of typical disc galaxies in the local Universe with the SDSS-IV/MaNGA survey, using the star formation rate surface density as an indicator for the gas surface density. We show that these three local parameters form a tight relationship, confirming previous works (e.g. by the PINGS and CALIFA surveys), but with a larger sample. We present a new local leaky-box model, assuming star-formation history and chemical evolution is localized except for outflowing materials. We derive closed-form solutions for the evolution of stellar surface density, …

Sdss-Iv Manga: Spatially Resolved Star Formation Histories In Galaxies As A Function Of Galaxy Mass And Type, D. Goddard, D. Thomas, C. Maraston, K. Westfall, J. Etherington, R. Riffel, M. D. Mallmann, Z. Zheng, M. Argudo-Fernández, J. Lian, M. Bershady, K. Bundy, N. Drory, D. Law, Renbin Yan, D. Wake, A. Weijmans, D. Bizyaev, J. Brownstein, R. R. Lane, R. Maiolino, K. Masters, M. Merrifield, C. Nitschelm, K. Pan, A. Roman-Lopes, T. Storchi-Bergmann, D. P. Schneider

Physics and Astronomy Faculty Publications

We study the internal gradients of stellar population properties within 1.5 R_e for a representative sample of 721 galaxies, with stellar masses ranging between 10⁹ M_⊙ and 10^11.5 M_⊙ from the SDSS-IV MaNGA Integral-Field-Unit survey. Through the use of our full spectral fitting code firefly, we derive light- and mass-weighted stellar population properties and their radial gradients, as well as full star formation and metal enrichment histories. We also quantify the impact that different stellar population models and full spectral fitting routines have on the derived stellar population properties and the radial gradient measurements. In …

Sdss-Iv Manga: The Impact Of Diffuse Ionized Gas On Emission-Line Ratios, Interpretation Of Diagnostic Diagrams And Gas Metallicity Measurements, Kai Zhang, Renbin Yan, Kevin Bundy, Matthew Bershady, L. Matthew Haffner, René Walterbos, Roberto Maiolino, Christy Tremonti, Daniel Thomas, Niv Drory, Amy Jones, Francesco Belfiore, Sebastian F. Sánchez, Aleksandar M. Diamond-Stanic, Dmitry Bizyaev, Christian Nitschelm, Brett Andrews, Jon Brinkmann, Joel R. Brownstein, Edmond Cheung, Cheng Li, David R. Law, Alexandre Roman Lopes, Daniel Oravetz, Kaike Pan, Thaisa Storchi Bergmann, Audrey Simmons

Physics and Astronomy Faculty Publications

Diffuse ionized gas (DIG) is prevalent in star-forming galaxies. Using a sample of 365 nearly face-on star-forming galaxies observed by Mapping Nearby Galaxies at APO, we demonstrate how DIG in star-forming galaxies impacts the measurements of emission-line ratios, hence the interpretation of diagnostic diagrams and gas-phase metallicity measurements. At fixed metallicity, DIG-dominated low Σ_Hα regions display enhanced [S II]/Hα, [N II]/Hα, [O II]/Hβ and [O I]/Hα. The gradients in these line ratios are determined by metallicity gradients and Σ_Hα. In line ratio diagnostic diagrams, contamination by DIG moves H II …

A Scuba-2 Survey Of Felobal Qsos. Are Felobals In A ‘Transition Phase’ Between Ulirgs And Qsos?, Giulio Violino, Kristen E. K. Coppin, Jason A. Stevens, Duncan Farrah, James E. Geach, Dave M. Alexander, Ryan Hickox

Dartmouth Scholarship

It is thought that a class of broad absorption line (BAL) QSOs, characterised by Fe absorption features in their UV spectra (called `FeLoBALs'), could mark a transition stage between the end of an obscured starburst event and a youthful QSO beginning to shed its dust cocoon, where Fe has been injected into the interstellar medium by the starburst. To test this hypothesis we have undertaken deep SCUBA-2 850 μm observations of a sample of 17 FeLoBAL QSOs with 0.89 ≤ z ≤ 2.78 and -23.31 ≤ MB ≤-28.50 to directly detect an excess in the thermal emission of the dust …

Sdss-Iv Manga – The Spatially Resolved Transition From Star Formation To Quiescence, Francesco Belfiore, Roberto Maiolino, Claudia Maraston, Eric Emsellem, Matthew A. Bershady, Karen L. Masters, Dmitry Bizyaev, Médéric Boquien, Joel R. Brownstein, Kevin Bundy, Aleksandar M. Diamond-Stanic, Niv Drory, Timothy M. Heckman, David R. Law, Olena Malanushenko, Audrey Oravetz, Kaike Pan, Alexandre Roman-Lopes, Daniel Thomas, Anne-Marie Weijmans, Kyle B. Westfall, Renbin Yan

Physics and Astronomy Faculty Publications

Using spatially resolved spectroscopy from SDSS-IV MaNGA we have demonstrated that low ionization emission-line regions (LIERs) in local galaxies result from photoionization by hot evolved stars, not active galactic nuclei, hence tracing galactic region hosting old stellar population where, despite the presence of ionized gas, star formation is no longer occurring. LIERs are ubiquitous in both quiescent galaxies and in the central regions of galaxies where star formation takes place at larger radii. We refer to these two classes of galaxies as extended LIER (eLIER) and central LIER (cLIER) galaxies, respectively. cLIERs are late-type galaxies primarily spread across the green …

Sdss-Iv Manga: A Serendipitous Observation Of A Potential Gas Accretion Event, Edmond Cheung, David V. Stark, Song Huang, Kate H. R. Rubin, Lihwai Lin, Christy Tremonti, Kai Zhang, Renbin Yan, Dmitry Bizyaev, Médéric Boquien

Physics and Astronomy Faculty Publications

The nature of warm, ionized gas outside of galaxies may illuminate several key galaxy evolutionary processes. A serendipitous observation by the MaNGA survey has revealed a large, asymmetric Hα complex with no optical counterpart that extends ≈8'' (≈6.3 kpc) beyond the effective radius of a dusty, starbursting galaxy. This Hα extension is approximately three times the effective radius of the host galaxy and displays a tail-like morphology. We analyze its gas-phase metallicities, gaseous kinematics, and emission-line ratios and discuss whether this Hα extension could be diffuse ionized gas, a gas accretion event, or something else. We find …

Sdss-Iv Manga Ifs Galaxy Survey—Survey Design, Execution, And Initial Data Quality, Renbin Yan, Kevin Bundy, David R. Law, Matthew A. Bershady, Brett Andrews, Brian Cherinka, Aleksandar M. Diamond-Stanic, Niv Drory, Nicholas Macdonald, José R. Sánchez-Gallego, Daniel Thomas, David A. Wake, Anne-Marie Weijmans, Kyle B. Westfall, Kai Zhang, Alfonso Aragón-Salamanca, Francesco Belfiore, Dmitry Bizyaev, Guillermo A. Blanc, Michael R. Blanton, Joel Brownstein, Michele Cappellari, Richard D'Souza, Eric Emsellem, Hai Fu, Patrick Gaulme, Mark T. Graham, Daniel Goddard, James E. Gunn, Paul Harding

Physics and Astronomy Faculty Publications

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 3622 to 10354 Å. The design of the survey is driven by a set of science requirements on the precision of estimates of the following properties: star formation rate surface density, gas metallicity, stellar population age, metallicity, and abundance ratio, and their gradients; stellar and gas kinematics; and enclosed gravitational mass as a function of radius. We describe …

The Quenching Timescale And Quenching Rate Of Galaxies, Jianhui Lian, Renbin Yan, Kai Zhang, Xu Kong

Physics and Astronomy Faculty Publications

The average star formation rate (SFR) in galaxies has been declining since the redshift of 2. A fraction of galaxies quench and become quiescent. We constrain two key properties of the quenching process: the quenching timescale and the quenching rate among galaxies. We achieve this by analyzing the galaxy number density profile in NUV−u color space and the distribution in NUV−u versus u − i color–color diagram with a simple toy-model framework. We focus on galaxies in three mass bins between 10¹⁰ and 10^10.6 M _⊙. In the NUV−u versus u − i color–color …

The Cosmic Web, And The Role Of Environment In Galaxy Evolution, Ryan Cybulski

Doctoral Dissertations

The Universe, on extra-galactic scales, is composed of a vast network of structures dubbed the “cosmic web”. One of the most fundamental discoveries about the evolution of galaxies is that their properties have a dependence on their location relative to this cosmic web (i.e., their environment). However, detailed studies of the environmental dependence on galaxy evolution have been extremely challenging due to the inherent complexity of the structures on the largest scales, a plethora of techniques being used to try to map the cosmic web, and other confounding factors, such as the masses of galaxies, that also affect their evolution. …

Sdss-Iv Manga: Stellar Population Gradients As A Function Of Galaxy Environment, D. Goddard, D. Thomas, C. Maraston, K. Westfall, J. Etherington, R. Riffel, M. D. Mallmann, Z. Zheng, M. Argudo-Fernández, M. A. Bershady, K. Bundy, N. Drory, D. Law, Renbin Yan, D. Wake, A. Weijmans, D. Bizyaev, J. Brownstein, R. R. Lane, R. Maiolino, K. Masters, M. Merrifield, C. Nitschelm, K. Pan, A. Roman-Lopes, T. Storchi-Bergmann

Physics and Astronomy Faculty Publications

We study the internal radial gradients of stellar population properties within 1.5 R_e and analyse the impact of galaxy environment. We use a representative sample of 721 galaxies with masses ranging between 10⁹ M_⊙ and 10^11.5 M_⊙ from the SDSS-IV survey MaNGA. We split this sample by morphology into early-type and late-type galaxies. Using the full spectral fitting code firefly, we derive the light and mass-weighted stellar population properties, age and metallicity, and calculate the gradients of these properties. We use three independent methods to quantify galaxy environment, namely the Nth nearest neighbour, the …

Sdss-Iv Manga: Properties Of Galaxies With Kinematically Decoupled Stellar And Gaseous Components, Yifei Jin, Yanmei Chen, Yong Shi, C. A. Tremonti, M. A. Bershady, M. Merrifield, E. Emsellem, Hai Fu, D. Wake, K. Bundy, Lihwai Lin, M. Argudo-Fernandez, Song Huang, D. V. Stark, T. Storchi-Bergmann, D. Bizyaev, J. Brownstein, J. Chisholm, Qi Guo, Lei Hao, Jian Hu, Cheng Li, Ran Li, K. L. Masters, E. Malanushenko, Kaike Pan, R. A. Riffel, A. Roman-Lopes, A. Simmons, D. Thomas, Renbin Yan

Physics and Astronomy Faculty Publications

We study the properties of 66 galaxies with kinematically misaligned gas and stars from MaNGA survey. The fraction of kinematically misaligned galaxies varies with galaxy physical parameters, i.e. M_*, SFR and sSFR. According to their sSFR, we further classify these 66 galaxies into three categories, 10 star-forming, 26 ‘Green Valley’ and 30 quiescent ones. The properties of different types of kinematically misaligned galaxies are different in that the star-forming ones have positive gradient in D_n4000 and higher gas-phase metallicity, while the green valley/quiescent ones have negative D_n4000 gradients and lower gas-phase metallicity on average. …

The Effect Of A Growing Black Hole On The Infrared Emission Of Dusty Galaxies In The Distant Universe, Allison Kirkpatrick

Doctoral Dissertations

The buildup of stellar and black hole mass peaked during z=1-3. Infrared (IR) luminous galaxies, which are massive and heavily dust obscured (L_IR > 10¹¹ L_sun), dominate the stellar growth during this era, and many are harboring a hidden active galactic nucleus (AGN). We have quantified the contribution of AGN heating to the infrared emission of a large sample of dusty, luminous galaxies from z=0.5-4 using Spitzer mid-IR spectroscopy, available for every source. We classify sources as star forming galaxies, AGN, or composites based on the presence of mid-IR continuum emission due to a dusty …

Sdss Iv Manga – Spatially Resolved Diagnostic Diagrams: A Proof That Many Galaxies Are Liers, Francesco Belfiore, Roberto Maiolino, Claudia Maraston, Eric Emsellem, Matthew A. Bershady, Karen L. Masters, Renbin Yan, Dmitry Bizyaev, Médéric Boquien, Joel R. Brownstein, Kevin Bundy, Niv Drory, Timothy M. Heckman, David R. Law, Alexandre Roman-Lopes, Kaike Pan, Letizia Stanghellini, Daniel Thomas, Anne-Marie Weijmans, Kyle B. Westfall

Physics and Astronomy Faculty Publications

We study the spatially resolved excitation properties of the ionized gas in a sample of 646 galaxies using integral field spectroscopy data from the Sloan Digital Sky Survey IV Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) programme. Making use of Baldwin–Philips–Terlevich diagnostic diagrams we demonstrate the ubiquitous presence of extended (kpc scale) low-ionization emission-line regions (LIERs) in both star-forming and quiescent galaxies. In star-forming galaxies LIER emission can be associated with diffuse ionized gas, most evident as extraplanar emission in edge-on systems. In addition, we identify two main classes of galaxies displaying LIER emission: ‘central LIER’ (cLIER) galaxies, where …

Stellar Mass–Gas-Phase Metallicity Relation At 0.5 ≤ Z ≤ 0.7: A Power Law With Increasing Scatter Toward The Low-Mass Regime, Yicheng Guo, David C. Koo, Yu Lu, John C. Forbes, Marc Rafelski, Jonathan R. Trump, Ricardo Amorín, Guillermo Barro, Romeel Davé, S. M. Faber, Nimish P. Hathi, Hassen Yesuf, Michael C. Cooper, Avishai Dekel, Puragra Guhathakurta, Evan N. Kirby, Anton M. Koekemoer, Pablo G. Pérez-González, Lihwai Lin, Jeffery A. Newman, Joel R. Primack, David J. Rosario, Christopher N. A. Willmer, Renbin Yan

Physics and Astronomy Faculty Publications

We present the stellar mass (M_*)–gas-phase metallicity relation (MZR) and its scatter at intermediate redshifts (0.5 ≤ z ≤ 0.7) for for 1381 field galaxies collected from deep spectroscopic surveys. The star formation rate (SFR) and color at a given M_* of this magnitude-limited (R ≲ 24 AB) sample are representative of normal star-forming galaxies. For masses below 10⁹ M_☉ our sample of 237 galaxies is ~10 times larger than those in previous studies beyond the local universe. This huge gain in sample size enables superior constraints on the MZR and its scatter …

Interpreting The Ionization Sequence In Star-Forming Galaxy Emission-Line Spectra, Chris T. Richardson, James T. Allen, Jack A. Baldwin, Paul C. Hewett, Gary J. Ferland, Anthony Crider, Helen Meskhidze

Physics and Astronomy Faculty Publications

High-ionization star-forming (SF) galaxies are easily identified with strong emission-line techniques such as the BPT diagram, and form an obvious ionization sequence on such diagrams. We use a locally optimally emitting cloud model to fit emission-line ratios that constrain the excitation mechanism, spectral energy distribution, abundances and physical conditions along the star formation ionization sequence. Our analysis takes advantage of the identification of a sample of pure SF galaxies, to define the ionization sequence, via mean field independent component analysis. Previous work has suggested that the major parameter controlling the ionization level in SF galaxies is the metallicity. Here we …

The Impact Of The Dusty Torus On Obscured Quasar Halo Mass Measurements, M. A. Dipompeo, J. C. Runnoe, R. C. Hickox, A. D. Myers, J. E. Geach

Dartmouth Scholarship

Recent studies have found that obscured quasars cluster more strongly and are thus hosted by dark matter haloes of larger mass than their unobscured counterparts. These results pose a challenge for the simplest unification models, in which obscured objects are intrinsically the same as unobscured sources but seen through a dusty line of sight. There is general consensus that a structure like a "dusty torus" exists, meaning that this intrinsic similarity is likely the case for at least some subset of obscured quasars. However, the larger host halo masses of obscured quasars implies that there is a second obscured population …

Dark Matter Halo Concentration And The Evolution Of Spiral Structure In N-Body, Barred Spiral Galaxies, Jazmin Esmeralda Berlanga Medina

Graduate Theses and Dissertations

Motivated by the evidence of relationships between pitch angle (the tightness of spiral arm structure in the disk), P, and various indicators of central mass concentration, as well as the theoretical relationship between halo mass concentration and the density of visible matter in the central part of the galaxy, we look at a possible relationship between P and cvir (the virial concentration of the dark matter halo) in N-body simulations of barred, spiral galaxies. We also look at the evolution of pitch angle over time in higher temporal resolution than any data currently available in the literature. We find that …

Candels Visual Classifications: Scheme, Data Release, And First Results, Jeyhan S. Kartaltepe, Mark Mozena, Dale D. Kocevski, Daniel H. Mcintosh, Jennifer Lotz, Eric F. Bell, Sandra M. Faber, Harry C. Ferguson, David C. Koo, Robert Bassett, Maksym Bernyk, Kirsten Blancato, Frederic Bournaud, Paolo Cassata, M. Castellano, Edmond Cheung, Christopher J. Conselice, D. Croton, Tomas Dahlen, Duilia F. De Mello, Laura Degroot, Jennifer Donley, Javiera Guedes, Norman A. Grogin, Nimish Hathi, Matt Hilton, Brett Hollon, Anton M. Koekemoer, Nick Liu, Ray A. Lucas

Physics and Astronomy Faculty Publications

We have undertaken an ambitious program to visually classify all galaxies in the five CANDELS fields down to H < 24.5 involving the dedicated efforts of over 65 individual classifiers. Once completed, we expect to have detailed morphological classifications for over 50,000 galaxies spanning 0 < z < 4 over all the fields, with classifications from 3 to 5 independent classifiers for each galaxy. Here, we present our detailed visual classification scheme, which was designed to cover a wide range of CANDELS science goals. This scheme includes the basic Hubble sequence types, but also includes a detailed look at mergers and interactions, the clumpiness of galaxies, k-corrections, and a variety of other structural properties. In this paper, we focus on the first field to be completed—GOODS-S, which has been classified at various depths. The wide area coverage spanning the full field (wide+deep+ERS) includes 7634 galaxies that have been classified by at least three different people. In the deep area of the field, 2534 galaxies have been classified by at least five different people at three different depths. With this paper, we release to the public …

The Nustar Extragalactic Surveys: Initial Results And Catalog From The Extended Chandra Deep Field South, J. R. Mullaney, A. Del-Moro, J. Aird, D. M. Alexander, F. M. Civano, R. C. Hickox

Dartmouth Scholarship

We present initial results and the source catalog from the NuSTAR survey of the Extended Chandra Deep Field South (hereafter, ECDFS) - currently the deepest contiguous component of the NuSTAR extragalactic survey program. The survey covers the full ~30 arcmin x 30 arcmin area of this field to a maximum depth of ~360 ks (~220 ks when corrected for vignetting at 3-24 keV), reaching sensitivity limits of ~1.3 x 10^-14 erg/cm2/s (3-8 keV), ~3.4 x 10^-14 erg/cm2/s (8-24 keV) and ~3.0 x 10^-14 erg/cm2/s (3-24 keV). Fifty four (54) sources are detected over the full field, although five of these …

A Remarkably Flat Relationship Between The Average Star Formation Rate And Agn Luminosity For Distant X-Ray Agn, F. Stanley, C. M. Harrison, D. M. Alexander, A. M. Swinbank, J. A. Aird, A. Del Moro, R. C. Hickox, J. R. Mullaney

Dartmouth Scholarship

In this study we investigate the relationship between the star formation rate, SFR, and AGN luminosity, L(AGN), for ~2000 X-ray detected AGN. The AGN span over three orders of magnitude in X-ray luminosity (10^(42) < L(2-8keV) < 10^(45.5) erg/s) and are in the redshift range z = 0.2 - 2.5. Using infrared (IR) photometry (8 - 500um), including deblended Spitzer and Herschel images and taking into account photometric upper limits, we decompose the IR spectral energy distributions into AGN and star formation components. Using the IR luminosities due to star formation, we investigate the average SFRs as a function of redshift and AGN luminosity. In agreement with previous studies, we find a strong evolution of the average SFR with redshift, tracking the observed evolution of the overall star forming galaxy population. However, we find that the relationship between the average SFR and AGN luminosity is flat at all redshifts and across all the AGN luminosities investigated; in comparison to previous studies, we find less scatter amongst the average SFRs across the wide range of AGN luminosities investigated. By comparing to empirical models, we argue that the observed flat relationship is due to short timescale variations in AGN luminosity, driven by changes in the mass accretion rate, which wash out any underlying correlations between SFR and L(AGN). Furthermore, we show that the exact form of the predicted relationship between SFR and AGN luminosity (and it's normalisation) is highly sensitive to the assumed intrinsic Eddington ratio distribution.

The Double Galaxy Cluster Abell 2465 – Ii. Star Formation In The Cluster, Gary A. Wegner, Devin S. Chu, Ho Seong Hwang

Dartmouth Scholarship

We investigate the star formation rate and its location in the major merger cluster Abell 2465 at z = 0.245. Optical properties of the cluster are described in Paper I. Measurements of the Hα and infrared dust emission of galaxies in the cluster were made with an interference filter centred on the redshifted line at a wavelength of 817 nm and utilized data from the WISE satellite 12 μm band. Imaging in the Johnson U and B bands was obtained, and along with SDSS u and r was used to study the blue fraction, which appears enhanced, as a further …

Evidence For (And Against) Progenitor Bias In The Size Growth Of Compact Red Galaxies, Stephanie K. Keating, Roberto G. Abraham, Ricardo Schiavon, Genevieve Graves, Ivana Damjanov, Renbin Yan, Jeffrey Newman, Luc Simard

Physics and Astronomy Faculty Publications

Most massive, passive galaxies are compact at high redshifts, but similarly compact massive galaxies are rare in the local universe. The most common interpretation of this phenomenon is that massive galaxies have grown in size by a factor of about five since redshift z = 2. An alternative explanation is that recently quenched massive galaxies are larger (a "progenitor bias"). In this paper, we explore the importance of progenitor bias by looking for systematic differences in the stellar populations of compact early-type galaxies in the DEEP2 survey as a function of size. Our analysis is based on applying the statistical …

Star Cluster Populations In Compact Groups Of Galaxies, Konstantin Fedotov

Electronic Thesis and Dissertation Repository

In this thesis, I have explored the star cluster populations of several compact groups of galaxies, based on observations with the Advanced Camera for Surveys and the Wide Field Camera 3 on the Hubble Space Telescope. Low velocity dispersions and high galaxy number densities, the conditions of compact groups (in particular Hickson Compact Groups), represent an environment with frequent and prolonged interactions. Such environment can trigger the formation of star cluster populations associated with specific events. The BVI study has shown that star clusters can be used as a powerful tool for studying such events triggered by mergers and …

Overview Of The Sdss-Iv Manga Survey: Mapping Nearby Galaxies At Apache Point Observatory, Kevin Bundy, Matthew A. Bershady, David R. Law, Renbin Yan, Niv Drory, Nicholas Macdonald, David A. Wake, Brian Cherinka, José R. Sánchez-Gallego, Anne-Marie Weijmans, Daniel Thomas, Christy Tremonti, Karen Masters, Lodovico Coccato, Aleksandar M. Diamond-Stanic, Alfonso Aragón-Salamanca, Vladimir Avila-Reese, Carles Badenes, Jésus Falcón-Barroso, Francesco Belfiore, Dmitry Bizyaev, Guillermo A. Blanc, Joss Bland-Hawthorn, Michael R. Blanton, Joel R. Brownstein, Nell Byler, Michele Cappellari, Charlie Conroy, Aaron A. Dutton, Eric Emsellem, Kai Zhang

Physics and Astronomy Faculty Publications

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. MaNGA will investigate the internal kinematic structure and composition of gas and stars in an unprecedented sample of 10,000 nearby galaxies. We summarize essential characteristics of the instrument and survey design in the context of MaNGA's key science goals and present prototype observations to demonstrate MaNGA's scientific potential. MaNGA employs dithered observations with 17 fiber-bundle integral field units that vary in …

On The Formation And Evolution Of Early-Type Galaxies, Christina Williams

Doctoral Dissertations

Galaxies in the local Universe are characterized by blue, star-forming disk galaxies, and red, massive early-type galaxies (ETGs) whose star-formation has been quenched early in the Universe's history. The ETGs are relics of the evolutionary processes that transform galaxies over cosmic time, but currently we still lack a comprehensive understanding of their evolution. An important link in the evolution of ETGs is that the first quenched galaxies (z~2) are both the most massive, and most compact, suggesting a physical connection between high stellar density and efficient, rapid cessation of star-formation. In this dissertation, I seek insight into the formation and …

The Gentle Growth Of Galaxies At High Redshifts In Overdense Environments, Emilio Romano-Díaz, Isaac Shlosman, Jun-Hwan Choi, Raphael Sadoun

Physics and Astronomy Faculty Publications

We have explored prevailing modes of galaxy growth for redshifts z ~ 6-14, comparing substantially overdense and normal regions of the universe, using high-resolution zoom-in cosmological simulations. Such rare overdense regions have been projected to host high-z quasars. We demonstrate that galaxies in such environments grow predominantly by a smooth accretion from cosmological filaments which dominates the mass input from major, intermediate, and minor mergers. We find that by z ~ 6, the accumulated galaxy mass fraction from mergers falls short by a factor of 10 of the cumulative accretion mass for galaxies in the overdense regions, and by …

The Inside-Out Growth Of The Most Massive Galaxies At 0.3 < Z < 0.9, Lei Bai, H. K. C. Yee, Renbin Yan, Eve Lee, David G. Gilbank, E. Ellingson, L. F. Barrientos, M. D. Gladders, B. C. Hsieh, I. H. Li

Physics and Astronomy Faculty Publications

We study the surface brightness profiles of a sample of brightest cluster galaxies (BCGs) with 0.3 < z < 0.9.

For the remainder of the abstract, please download this article or visit https://doi.org/10.1088/0004-637X/789/2/134

The Evolution Of And Starburst-Agn Connection In Luminous And Ultraluminous Infrared Galaxies And Their Link To Globular Cluster Formation, Stephanie L. Fiorenza

Dissertations, Theses, and Capstone Projects

The evolutionary connection between nuclear starbursts and active galactic nuclei (AGN) in luminous infrared galaxies (LIRGs; 1011o

Using new spectrophotometric data, I classify the primary source of IR radiation as being a nuclear starburst or a type of AGN by using the Baldwin-Phillips-Terlevich (BPT) diagrams. I show that for the U/LIRGs in my sample the properties that describe their nuclear starbursts and AGN (e.g. star formation rate (SFR), L[O III], optical D parameter, D4000, and EW(Hδ)) are independent of one another, ensuring that no biases affect correlations between these properties and objects' locations on the BPT diagrams. I then derive …