Research

Contour map of a strongly lensed galaxy

Star formation is one of the most important processes to have shaped the visible universe. Winds from massive stars and their supernovae pollute the interstellar and intergalactic medium with the heavy elements responsible for life, affecting the characteristics of future stellar populations and limiting the total number of stars formed. In order to understand the evolution of galaxies, it is therefore important to study how stars form from clouds of molecular gas in a variety of conditions throughout cosmic history, and especially during the epoch of peak star formation ~10 billion years ago (z~2-3).

A photo of a dish at the VLA I observe high-z galaxies' molecular gas using radio telescopes like the Karl G. Jansky Very Large Array (VLA) and the Atacama Large Millimeter/submillimeter Array (ALMA). My molecular gas observations, in conjunction with other multi-wavelength data, address the physical conditions and dynamical states of high-redshift star- forming galaxies, thereby helping determine their connection to local galaxies observed today.

My research addresses whether star formation efficiencies were genuinely higher in the early universe, the mechanisms which drive high star formation rates, the role of AGN in quenching periods of rapid star formation, and observational biases caused by gas and star formation tracers. I study both the statistical properties of galaxy populations and detailed characterizations of individual galaxies. For example, I am involved in the first high-frequency VLA survey to measure the cosmic molecular gas abundance at z~2.

Download Full CV For a complete list of my papers and presentations, see below or check out my CV.

Awards & Press

Publications Submitted or In Preparation

  1. Resolved Molecular Gas and Star Formation Properties of the Strongly Lensed Galaxy SDSS J0901+1814, C. E. Sharon, A. S. Tagore, A.J. Baker, J. Rivera, C. R. Keeton II, L. J. Tacconi, D. Lutz, D. J. Wilner, A. E. Shapley, H. Lin, T. Diehl, S. S. Allam, and D. L. Tucker, In preparation.
  2. The CO Luminosity Density at High-z (COLDz) Survey: A Sensitive Large Area Blind Search for Low-J CO Emission from Cold Gas in the Early Universe with the Karl G. Jansky Very Large Array, R. Pavesi, C. E. Sharon, D. Riechers et al., In preparation.

Refereed Publications

  1. CO-Free Star Formation and Black Hole Activity in 3C368 at z=1.131: Coeval Growth of Stellar and Supermassive Black Hole Masses, C. Lamarche, G. J. Stacey, D. Brisbin, C. Ferkinhoff, S. Hailey-Dunsheath, T. Nikola, D. Riechers, C. E. Sharon, H. Spoon, and A. Vishwas, 2017, ApJ, 836,123.
  2. ALMA Reveals Weak [NII] Emission in "Typical" Galaxies and Intense Starbursts at z=5-6, R. Pavesi, D. Riechers, P. Capak, C. Carilli, C. E. Sharon, G. Stacey, A. Karim, N. Scoville, and V. Smolcic, 2016, ApJ, 832, 151
  3. A Total Molecular Gas Mass Census in z~2-3 Star-forming Galaxies: Low-J CO Excitation Probes of Galaxies' Evolutionary States, C. E. Sharon, D. Riechers, J. Hodge, C. Carilli, F. Walter, A. Weiß, and K. Knudsen, 2016, ApJ, 827, 18.
  4. COLDz: Karl G. Jansky Very Large Array discovery of a gas-rich galaxy in COSMOS, L. Lentati, J. Wagg, C. L. Carilli, D. Riechers, P. Capak, F. Walter, M. Aravena, E. da Cunha, J. A. Hodge, R. J. Ivison, I. Smail, C. E. Sharon, E. Daddi, R. Decarli, M. Dickinson, M. Sargent, N. Scoville, & V. Smolcic, 2015, ApJ, 800, 67L.
  5. Excitation Conditions in the Multi-component Submillimeter Galaxy SMM J00266+1708, C. E. Sharon, A. J. Baker, A. I. Harris, L. J. Tacconi, D. Lutz, and S. N. Longmore, 2015, ApJ, 798, 133.
  6. VLA Mapping of the CO(1-0) Line in SMM J14011+0252, C. E. Sharon, A. J. Baker, A. I. Harris, and A. P. Thomson, 2013, ApJ, 765, 6
  7. JVLA imaging of 12CO J=1-0 and free-free emission in lensed submillimetre galaxies, A. P. Thomson, R. J. Ivison, I. Smail, A. M. Swinbank, A. Weiss, J. P. Kneib, P. P. Papadopoulos, A. J. Baker, C. E. Sharon, and G. A. van Moorsel, 2012, MNRAS, 425, 2203
  8. CO(J->1-0) in z>2 Quasar Host Galaxies: No Evidence for Extended Molecular Gas Reservoirs, D. A. Riechers, C. L. Carilli, R. J. Maddalena, J. Hodge, A. I. Harris, A. J. Baker, F. Walter, J. Wagg, P. A. Vanden Bout, A. Weiss, and C. E. Sharon, 2011, ApJ, 739, L32
  9. CO J=1-0 spectroscopy of four submillimeter galaxies with the Zpectrometer on the Green Bank Telescope, A. I. Harris, A. J. Baker, S. G. Zonak, C. E. Sharon, R. Genzel, K. Rauch, G. Watts, and R. Creager, 2010, ApJ, 723, 1139
  10. F, G, K, M Spectral Standards in the Y Band (0.95-1.11 um), C. E. Sharon, L. Hillenbrand, W. Fischer, and S. Edwards, 2010, AJ, 139: 646
  11. The X-ray luminosity function of AGN at z~3, J. Aird, K. Nandra, A. Georgakakis, E. S. Laird, C. C. Steidel, and C. E. Sharon, 2008, MNRAS, 387, 883

Approved Observing Proposals as PI

Scientific Presentations