Jonathan Blazek

About

Jonathan Blazek is an Assistant Professor in the Department of Physics at Northeastern University. His research focuses on observational and theoretical cosmology, with a primary emphasis on understanding the Universe through astronomical surveys that cover large areas of the sky. He develops modeling and statistical methods to connect these observations to the underlying cosmological model, with particular attention to applications of galaxy clustering and weak gravitational lensing to map out the structure of the Universe. Blazek utilizes analytic techniques, cosmological simulations, and novel applications of artificial intelligence in his work. He is actively involved in major research collaborations, including the Dark Energy Survey, the Rubin Observatory Dark Energy Science Collaboration, and the Roman Space Telescope. His efforts also include combining data sets from multiple experiments observing at different wavelengths and employing different techniques to produce the most informative tests of cosmological models. Prior to his current position, Blazek was a postdoctoral fellow at EPFL in Switzerland and at Ohio State University. He earned his Ph.D. from the University of California, Berkeley.

Research topics

• Astronomy
• Physics
• Astrophysics
• Chemistry
• Psychology

Selected publications

• Dark Energy Survey Year 3 results: Cosmological constraints from galaxy clustering and weak lensing

  Physical review. D/Physical review. D. · 2022 · 1090 citations

  Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAM

  DOI

• Dark Energy Survey Year 3 results: Cosmology from cosmic shear and robustness to modeling uncertainty

  Physical review. D/Physical review. D. · 2022 · 370 citations

  This work and its companion paper, Amon et al. [Phys. Rev. D 105, 023514 (2022)], present cosmic shear measurements and cosmological constraints from over 100 million source galaxies in the Dark Energy Survey (DES) Year 3 data. We constrain the lensing amplitude parameter ${S}_{8}\ensuremath{\equiv}{\ensuremath{\sigma}}_{8}\sqrt{{\mathrm{\ensuremath{\Omega}}}_{\mathrm{m}}/0.3}$ at the 3% level in $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$: ${S}_{8}=0.75{9}_{\ensuremath{-}0.023}^{+0.025}$ (68% C…

  DOI

• Dark energy survey year 3 results: Cosmological constraints from cluster abundances, weak lensing, and galaxy clustering

  Physical review. D/Physical review. D. · 2025-06-02 · 11 citations

  article

  DES Collaboration: Abbott, T.M.C. et al.

  PublisherDOI

• Superclustering with the Atacama Cosmology Telescope and Dark Energy Survey. II. Anisotropic Large-scale Coherence in Hot Gas, Galaxies, and Dark Matter

  The Astrophysical Journal · 2025-03-28 · 2 citations

  articleOpen access

  Abstract Statistics that capture the directional dependence of the baryon distribution in the cosmic web enable unique tests of cosmology and astrophysical feedback. We use constrained oriented stacking of thermal Sunyaev–Zel’dovich (tSZ) maps to measure the anisotropic distribution of hot gas 2.5–40 Mpc away from galaxy clusters embedded in massive filaments and superclusters. The cluster selection and orientation (at a scale of ∼15 Mpc) use Dark Energy Survey (DES) Year 3 data, while expanded…

  PublisherDOI

• Confronting cosmic shear astrophysical uncertainties: DES Year 3 revisited

  ArXiv.org · 2025-12-03 · 1 citations

  preprintOpen access

  Cosmology from weak gravitational lensing has been limited by astrophysical uncertainties in baryonic feedback and intrinsic alignments. By calibrating these effects using external data, we recover non-linear information, achieving a 2% constraint on the clustering amplitude, $S_8$, resulting in a factor of two improvement on the $Λ$CDM constraints relative to the fiducial Dark Energy Survey Year 3 model. The posterior, $S_8=0.832^{+0.013}_{-0.017}$, shifts by $1.5σ$ to higher values, in closer…

  PublisherOA PDFDOI

Recent grants

• Galaxy intrinsic alignments: A new window into structure in the Universe

  NSF · $401k · 2022–2026

Frequent coauthors

• A. Carnero Rosell

  281 shared

• L. N. da Costa

  Laboratório Interinstitucional de e-Astronomia

  271 shared

• D. Gruen

  266 shared

• E. Bertin

  Orange (France)

  250 shared

• A. Roodman

  SLAC National Accelerator Laboratory

  249 shared

• K. Kuehn

  Netherlands Institute for Radio Astronomy

  217 shared

• M. Carrasco Kind

  Urbana University

  203 shared

• J. Gschwend

  Laboratório Interinstitucional de e-Astronomia

  196 shared

Awards & honors

• NSF CAREER Award

Similar researchers at Northeastern University

• Albert-László Barabásih-234
• Lisa Feldman Barretth-169
• Arun Bansilh-80