Carnegie Mellon University

Department of Physics

Mellon College of Science

Hy Trac

Associate Professor

Astrophysics & Cosmology
Wean Hall 8307

lab website 

Prof. Hy Trac

Education & Professional Experience

PhD: University of Toronto (Canada), Astronomy & Astrophysics (2004)
B.Sc.: University of British Columbia (Canada), Physics and Astronomy (1999)

Curriculum ViTA

Associate Professor, Carnegie Mellon University, 20016–
Assistant Professor, Carnegie Mellon University, 2010–16
Post-doctoral Research: Harvard University, 2007–10
Post-doctoral Research: Princeton University, 2004–07

Research Interests

I am a theoretical and computational cosmologist whose scientific interests include cosmic evolution and structure formation. My work is generally centered on the development and application of numerical simulations to model and interpret the observable Universe. In cosmology, I am especially interested in complex problems involving the gas, stars, galaxies, quasars, and clusters of galaxies that provide information about the underlying dark matter and dark energy. In astrophysics, I would particularly like to work on star and planet formation and the development of planetary atmospheres. I also collaborate with machine learning experts and statisticians to apply modern approaches to improve multi-wavelength data analysis and numerical simulations. I am a member of the Atacama Cosmology Telescope (ACT), Sloan Digital Sky Survey (SDSS), and Large Synoptic Survey Telescope (LSST) collaborations.

Selected Publications

A. D'Aloisio, M. McQuinn, Hy Trac, Large opacity variations in the high-redshift Lyα forest: The signature of relic temperature fluctuations from patchy reionization, Astrophys. J. Lett. 813, L38 (2015)

Hy Trac, Renyue Cen, Philip Mansfield, SCORCH. I. The galaxy–halo connection in the first billion yearsThe Astrophysical Journal 813, 54 (2015) 

M. Ntampaka, H. Trac, D. J. Sutherland, N. Battaglia, B. Póczos, J. Schneider, A machine learning approach for dynamical mass measurements of galaxy clustersThe Astrophysical Journal 803, 50 (2015) 

Aravind Natarajan, Andrew R. Zentner, Nicholas Battaglia, Hy Trac, Systematic errors in the measurement of neutrino masses due to baryonic feedback processes: Prospects for stage IV lensing surveysPhys. Rev. D 90, 63516 (2014) 

P. La Plante, N. Battaglia, A. Natarajan, J. B. Peterson, H. Trac, R. Cen, A. Loeb, Reionization on large scales. IV. Predictions for the 21 cm signal incorporating the light cone effectThe Astrophysical Journal 789, 31 (2014) 

Jonathan L. Sievers et al.,The Atacama Cosmology Telescope: cosmological parameters from three seasons of data, JCAP 10, 060 (2013)

N. Battaglia, A. Natarajan, H. Trac, R. Cen, A. Loeb, Reionization on large scales. III. Predictions for low-ℓ cosmic microwave background polarization and high-ℓ kinetic Sunyaev-Zel’dovich observables,, The Astrophysical Journal 776, 83 (2013)

Xiaoying Xu, Shirley Ho, Hy Trac, Jeff Schneider, Barnabas Poczos, Michelle Ntampaka, A first look at creating mock catalogs with machine learning techniques, The Astrophysical Journal 772, 147 (2013)

Matthew Hasselfield et al., The Atacama Cosmology Telescope: Sunyaev-Zel’dovich selected galaxy clusters at 148 GHz from three seasons of dataJ. Cosmol. Astropart. Phys. 2013, 8 (2013)

Hy Trac, Paul Bode, Jeremiah P. Ostriker, Templates for the Sunyaev-Zel’dovich angular power spectrumThe Astrophysical Journal 727, 94 (2011)

HY Trac, Nickolay Y. Gnedin, Computer Simulations of Cosmic ReionizationAdvanced Science Letters 4, 228 (2011)

Hy Trac, Renyue Cen, Abraham Loeb, Imprint of Inhomogeneous Hydrogen Reionization on the Temperature Distribution of the Intergalactic MediumThe Astrophysical Journal 689, L81 (2008)

Hy Trac, Renyue Cen, Radiative Transfer Simulations of Cosmic Reionization. I. Methodology and Initial ResultsThe Astrophysical Journal 671, 1 (2007)

Hy Trac, Ue-Li Pen, Out-of-core hydrodynamic simulations for cosmological applicationsNew Astronomy 11, 273 (2006)

Hy Trac, A moving frame algorithm for high Mach number hydrodynamicsNew Astronomy 9, 443 (2004)

Hy Trac, Ue‐Li Pen, A Primer on Eulerian Computational Fluid Dynamics for AstrophysicsPubl Astron Soc Pac 115, 303 (2003)

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ORCID  Researcher ID