The Gas Consumption History to z ~ 4 (2009)
Bauermeister, Amber, Blitz, Leo, Ma, Chung-Pei
Using the observations of the star formation rate and HI densities to z ~ 4, with measurements of the Molecular Gas Depletion Rate (MGDR) and local density of H_2 at z = 0, we derive the history of...
When Should We Treat Galaxies as Isolated? (2009)
Hopkins, Philip F., Keres, Dusan, Ma, Chung-Pei, Quataert, Eliot
Traditionally, secular evolution is defined as evolution of systems where the internal growth of structure and instabilities dominates the growth via external drivers (e.g. accretion/mergers). Most...
Self-Regulated Black Hole Growth via Momentum Deposition in Galaxy Merger Simulations (2009)
DeBuhr, Jackson, Quataert, Eliot, Ma, Chung-Pei, Hopkins, Philip
We perform hydrodynamical simulations of major galaxy mergers using new methods for calculating the growth of massive black holes (BH) in galactic nuclei and their impact on the surrounding galaxy....
Is the Radial Profile of the Phase-Space Density of Dark Matter Halos a Power-Law? (2009)
Ma, Chung-Pei, Chang, Philip, Zhang, Jun
The latest cosmological N-body simulations find two intriguing properties for dark matter haloes: (1) their radial density profile, rho, is better fit by a form that flattens to a constant at the...
Dark Matter Halo Growth II: Diffuse Accretion and its Environmental Dependence (2009)
Dark matter haloes in Lambda CDM simulations grow by mergers with other haloes as well as accretion of "diffuse" non-halo material. We quantify the mass growth rates via these two processes,...
Compact High-Redshift Galaxies Are the Cores of the Most Massive Present-Day Spheroids (2009)
Hopkins, Philip F., Bundy, Kevin, Murray, Norman, Quataert, Eliot, Lauer, Tod, Ma, Chung-Pei
Observations suggest that effective radii of high-z massive spheroids are as much as a factor ~6 smaller than low-z galaxies of comparable mass. Given the apparent absence of low-z counterparts, this...
Mass Accretion Rates and Histories of Dark Matter Haloes (2009)
McBride, James, Fakhouri, Onsi, Ma, Chung-Pei
We use the extensive catalog of dark matter haloes from the Millennium simulation to investigate the statistics of the mass accretion histories (MAHs) and accretion rates of ~500,000 haloes from...
When Is Secular Evolution Important? (2009)
Hopkins, Philip F., Keres, Dusan, Ma, Chung-Pei, Quataert, Eliot
This abstract has been withdrawn.
Hopkins, Philip F., Somerville, Rachel S., Cox, Thomas J., Hernquist, Lars, Jogee, Shardha, Keres, Dusan, ...
Transformation of disks into spheroids via mergers is a well-accepted element of galaxy formation models. However, recent simulations have shown that bulge formation is suppressed in increasingly...
Environmental Dependence of Dark Matter Halo Growth I: Halo Merger Rates (2008)
In an earlier paper we quantified the mean merger rate of dark matter haloes as a function of redshift z, descendant halo mass M0, and progenitor halo mass ratio xi using the Millennium simulation of...
How to Grow a Healthy Merger Tree (2008)
Zhang, Jun, Fakhouri, Onsi, Ma, Chung-Pei
We investigate seven Monte Carlo algorithms -- four old and three new -- for constructing merger histories of dark matter halos using the extended Press-Schechter (EPS) formalism based on both the...
Zhang, Jun, Ma, Chung-Pei, Fakhouri, Onsi
Analytic models based on spherical and ellipsoidal gravitational collapse have been used to derive the mass functions of dark matter halos and their progenitors (the conditional mass function). The...
Metallicities and Physical Conditions in Star-forming Galaxies at z~1.0-1.5 (2008)
Liu, Xin, Shapley, Alice E., Coil, Alison L., Brinchmann, Jarle, Ma, Chung-Pei
We present a study of the mass-metallicity (M-Z) relation and H II region physical conditions in a sample of 20 star-forming galaxies at 1.0
The Nearly Universal Merger Rate of Dark Matter Haloes in Lambda-CDM Cosmology (2007)
We construct merger trees from the largest database of dark matter haloes to date provided by the Millennium simulation to quantify the merger rates of haloes over a broad range of descendant halo...
Dynamical Friction and Galaxy Merging Timescales (2007)
Boylan-Kolchin, Michael, Ma, Chung-Pei, Quataert, Eliot
The timescale for galaxies within merging dark matter halos to merge with each other is an important ingredient in galaxy formation models. Accurate estimates of merging timescales are required for...
Luminosity Dependence in the Fundamental Plane Projections of Elliptical Galaxies (2006)
Desroches, Louis-Benoit, Quataert, Eliot, Ma, Chung-Pei, West, Andrew A.
We analyze the fundamental plane projections of elliptical galaxies as a function of luminosity, using a sample of approximately 80,000 galaxies drawn from Data Release 4 (DR4) of the Sloan Digital...
Satellite Accretion Onto Massive Galaxies With Central Black Holes (2006)
Boylan-Kolchin, Michael, Ma, Chung-Pei
Minor mergers of galaxies are expected to be common in a hierarchical cosmology such as $\Lambda$CDM and have the potential to significantly affect galactic structure. In this paper we dissect the...
Boylan-Kolchin, Michael, Ma, Chung-Pei, Quataert, Eliot
Several recent observations suggest that gas-poor (dissipationless) mergers of elliptical galaxies contribute significantly to the build-up of the massive end of the red sequence. We perform a series...
Chemical Abundances of DEEP2 Star-forming Galaxies at 1.0 (2005)
Shapley, Alice E., Coil, Alison, Ma, Chung-Pei, Bundy, Kevin
We present the results of near-infrared spectroscopic observations for a sample of 12 star-forming galaxies at 1.0
The DEEP2 Galaxy Redshift Survey: Clustering of Groups and Group Galaxies at z~1 (2005)
Coil, Alison L., Gerke, Brian F., Newman, Jeffrey A., Ma, Chung-Pei, Yan, Renbin, Cooper, Michael C., ...
We study the clustering properties of groups and of galaxies in groups in the DEEP2 Galaxy Redshift Survey dataset at z~1. Four clustering measures are presented: 1) the group correlation function...
Impact of Dark Matter Substructure on the Matter and Weak Lensing Power Spectra (2005)
Hagan, Bradley, Ma, Chung-Pei, Kravtsov, Andrey V.
We explore the effect of substructure in dark matter halos on the power spectrum and bispectrum of matter fluctuations and weak lensing shear. By experimenting with substructure in a cosmological N =...
Dissipationless Mergers of Elliptical Galaxies and the Evolution of the Fundamental Plane (2005)
Boylan-Kolchin, Michael, Ma, Chung-Pei, Quataert, Eliot
We carry out numerical simulations of dissipationless major mergers of elliptical galaxies using initial galaxy models that consist of a dark matter halo and a stellar bulge with properties...
Core Formation in Galactic Nuclei Due to Recoiling Black Holes (2004)
Boylan-Kolchin, Michael, Ma, Chung-Pei, Quataert, Eliot
Anisotropic gravitational radiation from a coalescing black hole binary can impart a recoil velocity of up to several hundred km/s to the remnant black hole. We examine the effects of recoiling...
Effects of Ellipticity and Shear on Gravitational Lens Statistics (2004)
Huterer, Dragan, Keeton, Chuck, Ma, Chung-Pei
We study the effects of ellipticity in lens galaxies and external tidal shear from neighboring objects on the statistics of strong gravitational lenses. For isothermal lens galaxies normalized so...
Coil, Alison L., Newman, Jeffrey A., Kaiser, Nick, Davis, Marc, Ma, Chung-Pei, Kocevski, Dale D., ...
When applied to deep photometric catalogs, the two-point angular correlation function, w(theta), is a sensitive probe of the evolution of galaxy clustering properties. Here we present measurements of...
Are Halos of Collisionless Cold Dark Matter Collisionless? (2004)
Ma, Chung-Pei, Boylan-Kolchin, Michael
Much recent discussion about dark matter has been centered on two seemingly independent problems: the abundance of substructure in dark matter halos, and the cuspiness of the halos' inner density...
Major Mergers of Galaxy Haloes: Cuspy or Cored Inner Density Profile? (2003)
Boylan-Kolchin, Michael, Ma, Chung-Pei
We present the results from a series of collisionless N-body simulations of major mergers of galaxy dark matter haloes with density profiles having either inner cusps or cores. Our simulations range...
Singh, Shwetabh, Ma, Chung-Pei, Arons, Jonathan
We use the two-dimensional Kolmogorov-Smirnov (KS) test to study the correlation between the 60 cosmic ray events above 4x10^19 eV from the AGASA experiment and the positions of infrared luminous...
Huterer, Dragan, Ma, Chung-Pei
Strong gravitational lensing is a useful probe of both the intrinsic properties of the lenses and the cosmological parameters of the universe. The large number of model parameters and small sample of...
Schechter vs. Schechter: Sub-Arcsecond Gravitational Lensing and Inner Halo Profiles (2002)
Sub-arcsecond lensing statistics depend sensitively on the inner mass profiles of low-mass objects and the faint-end slopes of the Schechter luminosity function and the Press-Schechter mass function....
Singh, Shwetabh, Ma, Chung-Pei
We develop a method based on the collisionless Boltzmann equation to calculate the gravitational clustering of relic neutrinos in realistic cosmological models dominated by cold dark matter (CDM) and...
Linear and Second-Order Evolution of Cosmic Baryon Perturbations below 10^6 Solar Masses (2001)
Singh, Shwetabh, Ma, Chung-Pei
Studies of the growth of cosmic perturbations are typically focused on galactic scales and above. In this paper we investigate the evolution of perturbations in baryons, photons, and dark matter for...
Strong Gravitational Lensing and Dark Energy (2001)
Sarbu, Nick, Rusin, David, Ma, Chung-Pei
We investigate the statistics of gravitational lenses in flat, low-density cosmological models with different cosmic equations of state w. We compute the lensing probabilities as a function of image...
Nonlinear Kinetic Sunyaev-Zeldovich Effect (2001)
We derive fully nonlinear expressions for temperature fluctuations from the kinetic Sunyaev-Zeldovich (SZ) effect, the scattering of cosmic microwave background photons off hot electrons in bulk...
AMiBA: Array for Microwave Background Anisotropy (2000)
Lo, K. Y., Chiueh, T. H., Martin, R. N., Ng, Kin-Wang, Liang, H., Pen, Ue-li, ...
As part of a 4-year Cosmology and Particle Astrophysics (CosPA) Research Excellence Initiative in Taiwan, AMiBA $-$ a 19-element dual-channel 85-105 GHz interferometer array is being specifically...
Constraints on the Inner Mass Profiles of Lensing Galaxies from Missing Odd Images (2000)
Most gravitational lens systems consist of two or four observable images. The absence of detectable odd images allows us to place a lower limit on the power-law slope of the inner mass profile of...
What Does It Take to Stabilize Gravitational Clustering? (2000)
An analytical understanding of the strongly nonlinear regime of gravitational collapse has been difficult to achieve. The only insight has been the stable clustering hypothesis, which assumes that...
Narayanan, Vijay K., Spergel, David N., Davé, Romeel, Ma, Chung-Pei
High resolution N-body simulations of cold dark matter (CDM) models predict that galaxies and clusters have cuspy halos with excessive substructure. Observations reveal smooth halos with central...
We present an analytic model for the fully nonlinear power spectrum P and bispectrum Q of the cosmological mass density field. The model is based on physical properties of dark matter halos, with the...
We investigate the nonlinear two- and three-point correlation functions of the cosmological density field in Fourier space and test the popular hierarchical clustering model, that the three-point...
Lensed Arcs and Inner Structure of Abell 697 (1999)
Metzger, Mark R., Ma, Chung-Pei
We present new optical observations of the z=0.282 cluster Abell 697 from the Keck II telescope. Images show an unusual disturbed structure in the cD halo and a previously unknown faint gravitational...
The Mass Power Spectrum in Quintessence Cosmological Models (1999)
Ma, Chung-Pei, Caldwell, R. R., Bode, Paul, Wang, Limin
We present simple analytic approximations for the linear and fully evolved nonlinear mass power spectrum for spatially flat cold dark matter (CDM) cosmological models with quintessence (Q)....
Neutrinos and Dark Matter (1999)
In these lectures I highlight some key features of massive neutrinos in the context of cosmology. I first review the thermal history and the free-streaming kinematics of the uniform cosmic background...
Small, Todd, Ma, Chung-Pei, Sargent, Wallace, Hamilton, Donald
(abridged) We present a study of the nature and evolution of large-scale structure based on two independent redshift surveys of faint field galaxies conducted with the 176-fiber Norris Spectrograph...
Nonlinear Cosmological Structure Formation (1998)
I present a general discussion of the evolution and model-dependence of both the linear and nonlinear power spectrum of density fluctuations. The features of the linear power spectrum in cosmological...
Analytical Approximation to the Nonlinear Power Spectrum of Gravitational Clustering (1998)
This paper presents an analytical formula that closely approximates the fully nonlinear power spectrum of matter fluctuations for redshift $z\approx 5$ to 0 over a wide range of cosmologically...
Redshift Evolution of the Nonlinear Two-Point Correlation Function (1998)
This paper presents a detailed theoretical study of the two-point correlation function $\xi$ for both dark matter halos and the matter density field in five cosmological models with varying matter...
Ma, Chung-Pei, Small, Todd A., Sargent, Wallace L. W.
We present a summary report on a detailed study of the mass and dynamical state of the Corona Borealis supercluster using the largest redshift survey of this object to date. Extensive $N$-body...
Small, Todd A., Ma, Chung-Pei, Sargent, Wallace L. W., Hamilton, Donald
(Abridged) We present a study of the structure and dynamics of the Corona Borealis Supercluster (z ~ 0.07) based on the redshifts for 528 galaxies in the supercluster. The galaxy distribution within...
Cosmological Constraints from High-Redshift Damped Lyman-Alpha Systems (1997)
Ma, Chung-Pei, Bertschinger, Edmund, Hernquist, Lars, Weinberg, David H., Katz, Neal
Any viable cosmological model must produce enough structure at early epochs to explain the amount of gas associated with high-redshift damped Ly$\alpha$ systems. We study the evolution of damped...
This paper presents simple analytic approximations to the linear power spectra, linear growth rates, and rms mass fluctuations for both components in a family of cold+hot dark matter (CDM+HDM) models...
Cosmological Perturbation Theory in the Synchronous and Conformal Newtonian Gauges (1995)
Ma, Chung-Pei, Bertschinger, Edmund
This paper presents a systematic treatment of the linear theory of scalar gravitational perturbations in the synchronous gauge and the conformal Newtonian (or longitudinal) gauge. It differs from...
Massive Neutrinos and Galaxy Formation (1994)
We report the most recent results from high-resolution numerical simulations of structure formation in two flat cold+hot dark matter models with neutrino mass densities $\onu=0.2$ and 0.3. We find...
Do Galactic Systems Form Too Late in Cold+Hot Dark Matter Models? (1994)
Ma, Chung-Pei, Bertschinger, Edmund
The abundance of galactic systems at high redshifts can impose a strong constraint on the cold+hot dark matter (CDM+HDM) models. The hot component reduces the excessive small-scale power in the...
Cosmological Perturbation Theory in the Synchronous vs. Conformal Newtonian Gauge (1994)
Ma, Chung-Pei, Bertschinger, Edmund
We present a systematic treatment of the linear theory of scalar gravitational perturbations in the synchronous gauge and the conformal Newtonian (or longitudinal) gauge. We first derive the...
A Calculation of the Full Neutrino Phase Space in Cold+Hot Dark Matter Models (1993)
Ma, Chung-Pei, Bertschinger, Edmund
This paper presents a general-relativistic N-body technique for evolving the phase space distribution of massive neutrinos in linear perturbation theory. The method provides a much more accurate...
Baryon asymmetry and structure formation in our universe /--by Chung-Pei Ma. (1993)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1993.
SO(10) Cosmic Strings and Baryon Number Violation (1992)
SO(10) cosmic strings formed during the phase transition Spin(10) $\rightarrow$ SU(5) $\times{\cal Z}_2$ are studied. Two types of strings --- one effectively Abelian and one non-Abelian --- are...