Publications (158)
Recovery of the Power Spectrum of Mass Fluctuations from Observations of the Lyman-alpha Forest
Rupert A. C. Croft, David H. Weinberg, Neal Katz +1
We present a method to recover the shape and amplitude of the power spectrum of mass fluctuations, P(k), from observations of the high redshift \lya forest. The method is motivated…
Intergalactic Dust Extinction in Hydrodynamic Cosmological Simulations
Ying Zu, David H. Weinberg, Romeel Davé +4
Recently Menard et al. detected a subtle but systematic change in the mean color of quasars as a function of their projected separation from foreground galaxies, extending to comov…
Pressure Support vs. Thermal Broadening in the Lyman-alpha Forest II: Effects of the Equation of State on Transverse Structure
Molly S. Peeples, David H. Weinberg, Romeel Davé +2
We examine the impact of gas pressure on the transverse coherence of high-redshift (2 <= z <= 4) Lyman-alpha forest absorption along neighboring lines of sight that probe the gas J…
Simulations of Damped Lyman-Alpha and Lyman Limit Absorbers in Different Cosmologies: Implications for Structure Formation at High Redshift
Jeffrey P. Gardner, Neal Katz, Lars Hernquist +1
We use hydrodynamic cosmological simulations to study damped Lyman-alpha (DLA) and Lyman limit (LL) absorption at redshifts z=2-4 in five variants of the cold dark matter scenario.…
The COS Absorption Survey of Baryon Harbors (CASBaH): Warm-hot Circumgalactic Gas Reservoirs Traced by Ne VIII Absorption
Joseph N. Burchett, Todd M. Tripp, J. Xavier Prochaska +13
We survey the highly ionized circumgalactic media (CGM) of 29 blindly selected galaxies at 0.49 < z_(gal) < 1.44 based on high-S/N ultraviolet spectra of z > 1 QSOs and the galaxy…
Bayesian surface photometry analysis for early-type galaxies
D. H. Stalder, Reinaldo R. de Carvalho, Martin D. Weinberg +4
We explore the application of Bayesian image analysis to infer the properties of an SDSS early-type galaxy sample including AGN. We use GALPHAT (Yoon et al. 2010) with a Bayes-fact…
Enrichment of the Intergalactic Medium by Radiation Pressure Driven Dust Efflux
Anthony Aguirre, Lars Hernquist, Neal Katz +2
The presence of metals in hot cluster gas and in Ly-alpha absorbers, as well as the mass-metallicity relation of observed galaxies, suggest that galaxies lose a significant fractio…
Hydrogen and Metal Line Absorption Around Low-Redshift Galaxies in Cosmological Hydrodynamic Simulations
Amanda Brady Ford, Benjamin D. Oppenheimer, Romeel Davé +3
We study the physical conditions of the circum-galactic medium (CGM) around z=0.25 galaxies as traced by HI and metal line absorption, using cosmological hydrodynamic simulations t…
Bar-driven dark halo evolution: a resolution of the cusp--core controversy
Martin D. Weinberg, Neal Katz
Simulations predict that the dark matter halos of galaxies should have central cusps, while those inferred from observed galaxies do not have cusps. We demonstrate, using both line…
Torque-Limited Growth of Massive Black Holes in Galaxies Across Cosmic Time
Daniel Anglés-Alcázar, Feryal Ãzel, Romeel Davé +3
We combine cosmological hydrodynamic simulations with analytic models to evaluate the role of galaxy-scale gravitational torques on the evolution of massive black holes at the cent…
Galaxy Clustering and Galaxy Bias in a Lambda-CDM Universe
David H. Weinberg, Romeel Dav'e, Neal Katz +1
We investigate galaxy clustering and galaxy-mass correlations in the LCDM cosmological model using a large volume SPH simulation. For the most part, the predicted biases between ga…
Baryon Dynamics, Dark Matter Substructure, and Galaxies
David H. Weinberg, Stephane Colombi, Romeel Davé +1
By comparing a collisionless cosmological N-body simulation (DM) to an SPH simulation with the same initial conditions, we investigate the correspondence between the dark matter su…
Nature and completeness of galaxies detected in the Two Micron All Sky Survey
Daniel H. McIntosh, Eric F. Bell, Martin D. Weinberg +1
We cross correlate the well-defined and very complete spectroscopic Main Galaxy Sample (MGS) of 156,000 bright (r<17.5 mag) galaxies from the SDSS with 2MASS sources to explore the…
Analysis of the Lyman-alpha Forest in Cosmological Simulations Using Voigt-Profile Decomposition
Romeel Davé, Lars Hernquist, David H. Weinberg +1
We use an automated Voigt-profile fitting procedure to extract statistical properties of the Ly forest in a numerical simulation of an , cold dark matter (CDM) universe.…
The Robustness of Cosmological Hydrodynamic Simulation Predictions to Changes in Numerics and Cooling Physics
Shuiyao Huang, Neal Katz, Romeel Davé +8
We test and improve the numerical schemes in our smoothed particle hydrodynamics (SPH) code for cosmological simulations, including the pressure-entropy formulation (PESPH), a time…
The COS Absorption Survey of Baryon Harbors: Unveiling the Physical Conditions of Circumgalactic Gas through Multiphase Bayesian Ionization Modeling
Karl J. Haislmaier, Todd M. Tripp, Neal Katz +4
Quasar absorption systems encode a wealth of information about the abundances, ionization structure, and physical conditions in intergalactic and circumgalactic media. Simple (ofte…
LADUMA: Discovery of a luminous OH megamaser at
Marcin Glowacki, Jordan D. Collier, Amir Kazemi-Moridani +65
In the local Universe, OH megamasers (OHMs) are detected almost exclusively in infrared-luminous galaxies, with a prevalence that increases with IR luminosity, suggesting that they…
Time stepping N-body simulations
Thomas Quinn, Neal Katz, Joachim Stadel +1
Leapfrog integration has been the method of choice in N-body simulations owing to its low computational cost for a symplectic integrator with second order accuracy. We introduce a…
The Neutral Hydrogen Content of Galaxies in Cosmological Hydrodynamic Simulations
Romeel Davé, Neal Katz, Benjamin D. Oppenheimer +2
We examine the global HI properties of galaxies in quarter-billion particle cosmological simulations using Gadget-2, focusing on how galactic outflows impact HI content. We conside…
Creation of Peanut-Shaped Bulges via the Slow Mode of Bar Growth
Michael S. Petersen, Martin D. Weinberg, Neal Katz
Recent theoretical work has implicated fast bar formation modes and subsequent evolution as the creation mechanism for the observed peanut-shaped bulges in some edge-on disk galaxi…
Pressure Support vs. Thermal Broadening in the Lyman-alpha Forest I: Effects of the Equation of State on Longitudinal Structure
Molly S. Peeples, David H. Weinberg, Romeel Davé +2
In the low density intergalactic medium (IGM) that gives rise to the Lyman-alpha forest, gas temperature and density are tightly correlated. The velocity scale of thermal broadenin…
Cosmology with the Lyman-alpha Forest
David H. Weinberg, Scott Burles, Rupert A. C. Croft +11
We outline the physical picture of the high-redshift Ly-alpha forest that has emerged from cosmological simulations, describe statistical characteristics of the forest that can be…
Towards a Precise Measurement of Matter Clustering: Lyman-alpha Forest Data at Redshifts 2-4
Rupert A. C. Croft, David H. Weinberg, Mike Bolte +5
We measure the filling factor, correlation function, and power spectrum of transmitted flux in a large sample of Lya forest spectra, comprised of 30 Keck HIRES spectra and 23 Keck…
The Nature of Lyman Break Galaxies in Cosmological Hydrodynamic Simulations
Romeel Davé, Jeffrey P. Gardner, Lars Hernquist +2
What type of objects are being detected as "Lyman break galaxies"? Are they predominantly the most massive galaxies at that epoch, or are many of them smaller galaxies un…
Cooling Radiation and the Lyman-alpha Luminosity of Forming Galaxies
Mark A. Fardal, Neal Katz, Jeffrey P. Gardner +3
We examine the cooling radiation from forming galaxies in hydrodynamic simulations of the LCDM model (cold dark matter with a cosmological constant), focusing on the Ly-alpha line…
How Do Galaxies Get Their Gas?
Neal Katz, Dusan Keres, Romeel Dave +1
Not the way one might have thought. In hydrodynamic simulations of galaxy formation, some gas follows the traditionally envisioned route, shock heating to the halo virial temperatu…
Accretion, feedback and galaxy bimodality: a comparison of the GalICS semi-analytic model and cosmological SPH simulations
Andrea Cattaneo, Jeremy Blaizot, David H. Weinberg +6
We compare the galaxy population of an SPH simulation to those predicted by the GalICS semi-analytic model and a stripped down version without supernova and AGN feedback. The SPH s…
On the Destruction and Over-Merging of Dark Halos in Dissipationless N-body Simulations
Ben Moore, Neal Katz, George Lake
N-body simulations that follow only a collisionless dark matter component have failed to produce galaxy halos or substructure within dense environments. We investigate the `over-me…
Sub-mm Galaxies in Cosmological Simulations
Mark A. Fardal, Neal Katz, David H. Weinberg +2
We study the predicted sub-mm emission from massive galaxies in a Lambda-CDM universe, using hydrodynamic cosmological simulations. Assuming that most of the emission from newly fo…
The intergalactic medium over the last 10 billion years I: Lyman alpha absorption and physical conditions
Romeel Davé, Benjamin D. Oppenheimer, Neal Katz +2
The intergalactic medium (IGM) is the dominant reservoir of baryons at all cosmic epochs. We investigate the evolution of the IGM from z=2-0 in 48 Mpc/h, 110-million particle cosmo…
The growth of galaxies in cosmological simulations of structure formation
Chigurupati Murali, Neal Katz, Lars Hernquist +2
We use hydrodynamic simulations to examine how the baryonic components of galaxies are assembled, focusing on the relative importance of mergers and smooth accretion in the formati…
Physically Detached "Compact Groups"
Lars Hernquist, Neal Katz, David Weinberg
A small fraction of galaxies appear to reside in dense compact groups, whose inferred crossing times are much shorter than a Hubble time. These short crossing times have led to con…
Group Scaling Relations From a Cosmological Hydrodynamic Simulation: No Pre-heating Required?
Romeel Davé, Neal Katz, Lars Hernquist +1
We investigate the X-ray vs. optical scaling relations of poor groups to small clusters (sigma~100-700 km/s) identified in a cosmological hydrodynamic simulation of a Lambda-CDM un…
ELUCID VIII: Simulating the Coma Galaxy Cluster to Calibrate Model and Understand Feedback
Xiong Luo, Huiyuan Wang, Weiguang Cui +9
We conducted an investigation of the Coma cluster of galaxies by running a series of constrained hydrodynamic simulations with GIZMO-SIMBA and GADGET-3, based on initial conditions…
High-Redshift Galaxies in Cold Dark Matter Models
David H. Weinberg, Lars Hernquist, Neal Katz
We use hydrodynamic cosmological simulations to predict the star formation properties of high-redshift galaxies (z=2-6) in five variants of the inflationary cold dark matter scenar…
Cosmological Simulations with TreeSPH
Neal Katz, David H. Weinberg, Lars Hernquist
We describe numerical methods for incorporating gas dynamics into cosmological simulations and present illustrative applications to the cold dark matter (CDM) scenario. Our evoluti…
The COS-Halos Survey: Rationale, Design, and A Census of Circumgalactic Neutral Hydrogen
Jason Tumlinson, Christopher Thom, Jessica Werk +11
We present the design and methods of the COS-Halos survey, a systematic investigation of the gaseous halos of 44 z = 0.15-0.35 galaxies using background QSOs observed with the Cosm…
Cosmology from the structure of the Lyman-alpha forest
Rupert Croft, David Weinberg, Neal Katz +1
A convincing physical picture for the Lyman-alpha forest has emerged from simulations and related semi-analytic studies of structure formation models. Observations can be be used i…
Probing Galaxy Formation with He II Cooling Lines
Yujin Yang, Ann I. Zabludoff, Romeel Davé +5
Using high resolution cosmological simulations, we study hydrogen and helium gravitational cooling radiation. We focus on the HeII cooling lines, which arise from gas with a differ…
Cosmological Simulations with Scale-Free Initial Conditions I: Adiabatic Hydrodynamics
J. Michael Owen, David H. Weinberg, August E. Evrard +2
We analyze hierarchical structure formation based on scale-free initial conditions in an Einstein-de Sitter universe, including a baryonic component. We present three independent,…
The impact of environment and mergers on the HI content of galaxies in hydrodynamic simulations
Mika Rafieferantsoa, Romeel Davé, Daniel Anglés-Alcazar +3
We quantitatively examine the effects of accretion and environment on the HI content of galaxies within a cosmological hydrodynamic simulation that reproduces basic observed trends…
A New Model For Including Galactic Winds in Simulations of Galaxy Formation I: Introducing the Physically Evolved Winds (PhEW) Model
Shuiyao Huang, Neal Katz, Evan Scannapieco +5
The propagation and evolution of cold galactic winds in galactic haloes is crucial to galaxy formation models. However, modelling of this process in hydrodynamic simulations of gal…
On the Relationship between Cooling Flows and Bubbles
Ian G. McCarthy, Arif Babul, Neal Katz +1
A common feature of the X-ray bubbles observed in Chandra images of some "cooling flow" clusters is that they appear to be surrounded by bright, cool shells. Temperature maps of a…
The dynamics of tidal tails from massive satellites
Jun-Hwan Choi, Martin D. Weinberg, Neal Katz
(Abbreviated) We investigate the dynamical mechanisms responsible for producing tidal tails from dwarf satellites using N-body simulations. We identify two important dynamical co-c…
nIFTy galaxy cluster simulations I: dark matter & non-radiative models
Federico Sembolini, Gustavo Yepes, Frazer R. Pearce +24
We have simulated the formation of a galaxy cluster in a CDM universe using twelve different codes modeling only gravity and non-radiative hydrodynamics (\art, \arepo, \hydra\…
Damped Lyman-alpha and Lyman Limit Absorbers in the Cold Dark Matter Model
Neal Katz, David H. Weinberg, Lars Hernquist +1
We study the formation of damped \lya and Lyman limit absorbers in a hierarchical clustering scenario using a gas dynamical simulation of an , cold dark matter universe. In…
Theoretical Modeling of the High Redshift Galaxy Population
David H. Weinberg, Romeel Dave', Jeffrey P. Gardner +2
We review theoretical approaches to the study of galaxy formation, with emphasis on the role of hydrodynamic simulations in modeling the high redshift galaxy population. We present…
The intergalactic medium over the last 10 billion years II: Metal-line absorption and physical conditions
Benjamin D. Oppenheimer, Romeel Davé, Neal Katz +2
We investigate the metallicity evolution and content of the intergalactic medium (IGM) and galactic halo gas from z=2->0 using 110-million particle cosmological hydrodynamic simula…
Galaxy Merger Statistics and Inferred Bulge-to-Disk Ratios in Cosmological SPH Simulations
Ariyeh Maller, Neal Katz, Dusan Keres +2
We construct merger trees for galaxies identified in a cosmological hydrodynamical simulation and use them to characterize predicted merger rates as a function of redshift, galaxy…
Preheating by Previrialization and its Impact on Galaxy Formation
H. J. Mo, Xiaohu Yang, Frank C. van den Bosch +1
We use recent observations of the HI-mass function to constrain galaxy formation. The data conflicts with the standard model where most of the gas in a low-mass dark matter halo is…
Bar-Induced Evolution of Dark Matter Cusps
Kelly Holley-Bockelmann, Martin Weinberg, Neal Katz
The evolution of a stellar bar transforms not only the galactic disk, but also the host dark matter halo. We present high resolution, fully self-consistent N-body simulations that…
Parametrising Star Formation Histories
Vimal Simha, David H. Weinberg, Charlie Conroy +4
We examine the star formation histories (SFHs) of galaxies in smoothed particle hydrodynamics (SPH) simulations, compare them to parametric models that are commonly used in fitting…
Star Formation and Feedback in Smoothed Particle Hydrodynamic Simulations--I. Isolated Galaxies
Greg Stinson, Anil Seth, Neal Katz +3
We present an analysis of star formation and feedback recipes appropriate for galactic smoothed particle hydrodynamics simulations. Using an isolated Milky Way-like galaxy, we cons…
Using Harmonic Decomposition to Understand Barred Galaxy Evolution
Michael S. Petersen, Martin D. Weinberg, Neal Katz
We study the mechanisms and evolutionary phases of bar formation in n-body simulations of a stellar disc and dark matter halo system using harmonic basis function expansion analysi…
The Growth and Enrichment of the Intragroup Gas
Lichen Liang, Fabrice Durier, Arif Babul +5
The thermal and chemical properties of the hot diffuse intragroup medium (IGrM) provide important constraints on the feedback processes associated with massive galaxy formation and…
Voigt-Profile Analysis of the Lyman-alpha Forest in a Cold Dark Matter Universe
Romeel Davé, Lars Hernquist, David Weinberg +1
We use an automated Voigt-profile fitting procedure to extract statistical properties of the Ly forest in a numerical simulation of an , cold dark matter (CDM) universe.…
The Galaxy Proximity Effect in the Lyman-alpha Forest
Juna A. Kollmeier, David H. Weinberg, Romeel Dave' +1
Hydrodynamic cosmological simulations predict that the average opacity of the Ly-alpha forest should increase in the neighborhood of galaxies because galaxies form in dense environ…
Building Galaxies with Simulations
Romeel Davé, Kristian Finlator, Lars Hernquist +4
We present an overview of some of the issues surrounding current models of galaxy formation, highlighting recent insights obtained from cosmological hydrodynamic simulations. Detai…
Cosmological Constraints from High-Redshift Damped Lyman-Alpha Systems
Chung-Pei Ma, Edmund Bertschinger, Lars Hernquist +2
Any viable cosmological model must produce enough structure at early epochs to explain the amount of gas associated with high-redshift damped Ly systems. We study the evolution…
A Budget and Accounting of Metals at z~0: Results from the COS-Halos Survey
Molly S. Peeples, Jessica K. Werk, Jason Tumlinson +4
We present a budget and accounting of metals in and around star-forming galaxies at . We combine empirically derived star formation histories with updated supernova and AG…
Ongoing Assembly of Massive Galaxies by Major Merging in Large Groups and Clusters from the SDSS
Daniel H. McIntosh, Yicheng Guo, Jen Hertzberg +4
We investigate the incidence of major mergers creating >10e11 Msun galaxies in present-day groups and clusters more massive than 2.5e13 Msun. We identify 38 pairs of massive galaxi…
nIFTy galaxy cluster simulations V: Investigation of the Cluster Infall Region
Jake Arthur, Frazer R. Pearce, Meghan E. Gray +19
We examine the properties of the galaxies and dark matter haloes residing in the cluster infall region surrounding the simulated CDM galaxy cluster studied by Elahi et al. (201…
Ion densities of cold clouds driven by galactic outflows
Lisiyuan Yang, Neal Katz, Evan Scannapieco +1
Observations of the circumgalactic medium (CGM) often display coincident absorption from species with widely varying ionization states, providing direct evidence for complex, multi…
Star Formation and Stellar Mass Assembly in Dark Matter Halos: From Giants to Dwarfs
Zhankui Lu, H. J. Mo, Yu Lu +4
The empirical model of Lu et al. 2014 is updated with recent data and used to study galaxy star formation and assembly histories. At , the predicted galaxy stellar mass func…
The Halo Occupation Distribution and the Physics of Galaxy Formation
Andreas A. Berlind, David H. Weinberg, Andrew J. Benson +7
The halo occupation distribution (HOD) describes the bias between galaxies and dark matter by specifying (a) the probability P(N|M) that a halo of virial mass M contains N galaxies…
X-Ray Scaling Relations of Galaxy Groups in a Hydrodynamic Cosmological Simulation
Romeel Davé, Neal Katz, David H. Weinberg
We examine the scalings of X-ray luminosity, temperature, and dark matter or galaxy velocity dispersion for galaxy groups in an LCDM cosmological simulation, which incorporates gra…
From Galaxy-Galaxy Lensing to Cosmological Parameters
Jaiyul Yoo, Jeremy L. Tinker, David H. Weinberg +3
Galaxy-galaxy lensing measures the mean excess surface density DS(r) around a sample of lensing galaxies. We develop a method for combining DS(r) with the galaxy correlation functi…
The Galaxy Angular Correlation Functions and Power Spectrum from the Two Micron All Sky Survey
Ariyeh H. Maller, Daniel H. McIntosh, Neal Katz +1
We calculate the angular correlation function of galaxies in the Two Micron All Sky Survey. We minimize the possible contamination by stars, dust, seeing and sky brightness by stud…
The Power Spectrum of Mass Fluctuations Measured from the Lyman-alpha Forest at Redshift z=2.5
Rupert A. C. Croft, David H. Weinberg, Max Pettini +2
We measure the linear power spectrum of mass density fluctuations at redshift z=2.5 from the \lya forest absorption in a sample of 19 QSO spectra, using the method introduced by Cr…
nIFTY galaxy cluster simulations III: The Similarity & Diversity of Galaxies & Subhaloes
Pascal J. Elahi, Alexander Knebe, Frazer R. Pearce +17
We examine subhaloes and galaxies residing in a simulated LCDM galaxy cluster () produced by hydrodynamical codes ranging from classic…
The High-Ion Content and Kinematics of Low-Redshift Lyman Limit Systems
Andrew J. Fox, Nicolas Lehner, Jason Tumlinson +9
We study the high-ionization phase and kinematics of the circumgalactic medium around low-redshift galaxies using a sample of 23 Lyman Limit Systems (LLSs) at 0.08<z<0.93 observed…
Photoionization and the Formation of Dwarf Galaxies
Thomas Quinn, Neal Katz, George Efstathiou
It has been argued that a UV photoionizing background radiation field suppresses the formation of dwarf galaxies, and may even inhibit the formation of larger galaxies. In order to…
The Optical and Near-Infrared Properties of Galaxies: I. Luminosity and Stellar Mass Functions
Eric F. Bell, Daniel H. McIntosh, Neal Katz +1
We use a large sample of galaxies from the Two Micron All Sky Survey (2MASS) and the Sloan Digital Sky Survey (SDSS) to calculate galaxy luminosity and stellar mass functions in th…
Interpreting the Relationship Between Galaxy Luminosity, Color and Environment
Andreas A. Berlind, Michael R. Blanton, David W. Hogg +5
We study the relationship between galaxy luminosity, color, and environment in a cosmological simulation of galaxy formation. We compare the predicted relationship with that found…
An Empirical Model for the Star Formation History in Dark Matter Halos
Zhankui Lu, Houjun Mo, Yu Lu +4
We develop an empirical approach to infer the star formation rate in dark matter halos from the galaxy stellar mass function (SMF) at different redshifts and the local cluster gala…
New insight on galaxy structure from GALPHAT I. Motivation, methodology, and benchmarks for Sersic models
Ilsang Yoon, Martin Weinberg, Neal Katz
We introduce a new galaxy image decomposition tool, GALPHAT (GALaxy PHotometric ATtributes), to provide full posterior probability distributions and reliable confidence intervals f…
Galaxies in a Simulated CDM Universe II: Observable Properties and Constraints on Feedback
Dušan Kereš, Neal Katz, Romeel Dave +2
We compare the properties of galaxies that form in a cosmological simulation without strong feedback to observations at z=0. We confirm previous findings that models without strong…
A Bayesian approach to the semi-analytic model of galaxy formation: methodology
Yu Lu, H. J. Mo, Martin D. Weinberg +1
We believe that a wide range of physical processes conspire to shape the observed galaxy population but we remain unsure of their detailed interactions. The semi-analytic model (SA…
Characterization of Lyman Alpha Spectra and Predictions of Structure Formation Models: A Flux Statistics Approach
Rupert A. C. Croft, David H. Weinberg, Lars Hernquist +1
In gravitational instability models, \lya absorption arises from a continuous fluctuating medium, so that spectra provide a non-linear one-dimensional ``map'' of the underlying den…
Metal Lines in Cosmological Models of Lyman-Alpha Absorbers
Uffe Hellsten, Lars Hernquist, Neal Katz +1
The metal absorption lines found in association with \lya absorbers of moderate to high HI column density contain valuable information about the metallicity and ionization conditio…
Metal Lines Associated with Lyman Alpha Absorbers: A Comparison of Theory and Observations
Uffe Hellsten, Romeel Dave, Lars Hernquist +2
We study metal line absorption of CIV, CII, SiIV, and NV at redshifts z=3.5 to z=2 within the framework of a cosmological model for the Lyman alpha forest, comparing the results of…
A Deep Search For Faint Galaxies Associated With Very Low-redshift C IV Absorbers: III. The Mass- and Environment-dependent Circumgalactic Medium
Joseph N. Burchett, Todd M. Tripp, Rongmon Bordoloi +6
Using Hubble Space Telescope Cosmic Origins Spectrograph observations of 89 QSO sightlines through the Sloan Digital Sky Survey footprint, we study the relationships between C IV a…
Galaxies in a simulated CDM Universe I: cold mode and hot cores
Dušan Kereš, Neal Katz, Mark Fardal +2
We study the formation of galaxies in a (50 Mpc/h)^3 cosmological simulation (2x288^3 particles), evolved using the entropy conserving SPH code Gadget-2. Most of the baryonic mass…
Theoretical Models of the Halo Occupation Distribution: Separating Central and Satellite Galaxies
Zheng Zheng, Andreas A. Berlind, David H. Weinberg +7
The halo occupation distribution (HOD) describes the relation between galaxies and dark matter at the level of individual dark matter halos. The properties of galaxies residing at…
Dark Matter Trapping by Stellar Bars: The Shadow Bar
Michael S. Petersen, Martin D. Weinberg, Neal Katz
We investigate the complex interactions between the stellar disc and the dark-matter halo during bar formation and evolution using N-body simulations with fine temporal resolution…
Intergalactic Helium Absorption in Cold Dark Matter Models
Rupert A. C. Croft, David H. Weinberg, Neal Katz +1
Observations from the HUT and the HST have recently detected HeII absorption along the lines of sight to two high redshift quasars. We use cosmological simulations with gas dynamic…
Photoionization, Numerical Resolution, and Galaxy Formation
David H. Weinberg, Lars Hernquist, Neal Katz
Using cosmological simulations that incorporate gas dynamics and gravitational forces, we investigate the influence of photoionization by a UV radiation background on the formation…
The Lyman-alpha Forest as a Cosmological Tool
David H. Weinberg, Romeel Dav'e, Neal Katz +1
We review recent developments in the theory of the Lyman-alpha forest and their implications for the role of the forest as a test of cosmological models. Simulations predict a rela…
The dynamics of satellite disruption in cold dark matter haloes
Jun-Hwan Choi, Martin D. Weinberg, Neal Katz
We investigate the physical mechanisms of tidal heating and satellite disruption in cold dark matter host haloes using N-body simulations based on cosmological initial conditions.…
Testing Cosmological Models Against the Abundance of Damped Lyman-Alpha Absorbers
Jeffrey P. Gardner, Neal Katz, David H. Weinberg +1
We calculate the number of damped Lyman-alpha absorbers expected in various popular cosmological models as a function of redshift and compare our predictions with observed abundanc…
Lyman Break Galaxies and the Lyman-alpha Forest
Juna A. Kollmeier, David H. Weinberg, Romeel Dave' +1
We use hydrodynamic simulations to predict correlations between Lya forest absorption and galaxies at redshift z~3. The probability distribution function (PDF) of Lya flux decremen…
Tracing Inflows and Outflows with Absorption Lines in Circumgalactic Gas
Amanda Brady Ford, Romeel Davé, Benjamin D. Oppenheimer +4
We examine how HI and metal absorption lines within low-redshift galaxy halos trace the dynamical state of circumgalactic gas, using cosmological hydrodynamic simulations that incl…
Morphological Transformation from Galaxy Harassment
Ben Moore, George Lake, Neal Katz
Galaxy morphologies in clusters have undergone a remarkable transition over the past several billion years. Distant clusters at are filled with small spiral galaxies,…
The Lyman-alpha Forest in the Cold Dark Matter Model
Lars Hernquist, Neal Katz, David H. Weinberg +1
Cosmological simulations with gas provide a detailed description of the intergalactic medium, making possible predictions of neutral hydrogen absorption in the spectra of backgroun…
Measuring the Halo Mass of z=3 Damped Ly-alpha Absorbers from the Absorber-Galaxy Cross-correlation
Nicolas Bouche, Jeffrey P. Gardner, David H. Weinberg +3
[Abridged] We test the reliability of a method to measure the mean halo mass of Damped Ly-alpha absorbers (DLAs). The method is based on measuring the ratio of the cross-correlatio…
The Bimodal Absorption System Imaging Campaign (BASIC) I. A Dual Population of Low-metallicity Absorbers at z
Michelle A. Berg, Nicolas Lehner, J. Christopher Howk +17
The bimodal absorption system imaging campaign (BASIC) aims to characterize the galaxy environments of a sample of 36 HI-selected partial Lyman limit systems (pLLSs) and Lyman limi…
Lyman Alpha Flux Power Spectrum and Its Covariance
Hu Zhan, Romeel Dave, Daniel Eisenstein +1
We analyze the flux power spectrum and its covariance using simulated Lyman alpha forests. We find that pseudo-hydro techniques are good approximations of hydrodynamical simulation…
Bayesian inferences of galaxy formation from the K-band luminosity and HI mass functions of galaxies: constraining star formation and feedback
Yu Lu, H. J. Mo, Zhankui Lu +2
We infer mechanisms of galaxy formation for a broad family of semi-analytic models (SAMs) constrained by the K-band luminosity function and HI mass function of local galaxies using…
The Observability of Metal Lines Associated with the Lyman-alpha Forest
Uffe Hellsten, Lars Hernquist, Neal Katz +1
We develop a prescription for characterizing the strengths of metal lines associated with Lyman-alpha forest absorbers (LYFAs) of a given neutral hydrogen column density N_HI and m…
Using Torque to Understand Barred Galaxy Models
Michael S. Petersen, Martin D. Weinberg, Neal Katz
We track the angular momentum transfer in n-body simulations of barred galaxies by measuring torques to understand the dynamical mechanisms responsible for the evolution of the bar…