1.3k citations · 2.8k across the 23 of their papers we have counts for
23 papers
Improving IGM temperature constraints using wavelet analysis on high-redshift quasars
Molly Wolfson, Joseph F. Hennawi, Frederick B. Davies +3
The thermal state of the intergalactic medium (IGM) contains vital information about the epoch of reionization, one of the most transformative yet poorly understood periods in the…
HyPhy: Deep Generative Conditional Posterior Mapping of Hydrodynamical Physics
Benjamin Horowitz, Max Dornfest, Zarija Lukić +1
Generating large volume hydrodynamical simulations for cosmological observables is a computationally demanding task necessary for next generation observations. In this work, we con…
Fast, high-fidelity Lyman forests with convolutional neural networks
Peter Harrington, Mustafa Mustafa, Max Dornfest +2
Full-physics cosmological simulations are powerful tools for studying the formation and evolution of structure in the universe but require extreme computational resources. Here, we…
Estimating Galactic Distances From Images Using Self-supervised Representation Learning
Md Abul Hayat, Peter Harrington, George Stein +2
We use a contrastive self-supervised learning framework to estimate distances to galaxies from their photometric images. We incorporate data augmentations from computer vision as w…
Self-Supervised Representation Learning for Astronomical Images
Md Abul Hayat, George Stein, Peter Harrington +2
Sky surveys are the largest data generators in astronomy, making automated tools for extracting meaningful scientific information an absolute necessity. We show that, without the n…
The Power Spectrum of the Lyman- Forest at z < 0.5
Vikram Khaire, Michael Walther, Joseph F. Hennawi +6
We present new measurements of the flux power-spectrum P(k) of the HI Lyman- forest spanning scales k ~ 0.001-0.1 s/km. These results were derived from 65 far ultraviole…
New Constraints on IGM Thermal Evolution from the Lyα Forest Power Spectrum
Michael Walther, Jose Oñorbe, Joseph F. Hennawi +1
We determine the thermal evolution of the intergalactic medium (IGM) over of cosmic time by comparing measurements of the Lyα forest power spectrum t…
Quantitative Constraints on the Reionization History from the IGM Damping Wing Signature in Two Quasars at z > 7
Frederick B. Davies, Joseph F. Hennawi, Eduardo Bañados +10
During reionization, neutral hydrogen in the intergalactic medium (IGM) imprints a damping wing absorption feature on the spectrum of high-redshift quasars. A detection of this sig…
Modeling the HeII Transverse Proximity Effect: Constraints on Quasar Lifetime and Obscuration
Tobias M. Schmidt, Joseph F. Hennawi, Gábor Worseck +3
The HeII transverse proximity effect - enhanced HeII Lyα transmission in a background sightline caused by the ionizing radiation of a foreground quasar - offers a unique opportunit…
A Detection of ~2.3 Cosmic Voids from 3D Lyman- Forest Tomography in the COSMOS Field
Alex Krolewski, Khee-Gan Lee, Martin White +10
We present the most distant detection of cosmic voids () and the first detection of three-dimensional voids in the Lyman- forest. We used a 3D tomographic map of the…
DESCQA: An Automated Validation Framework for Synthetic Sky Catalogs
Yao-Yuan Mao, Eve Kovacs, Katrin Heitmann +24
The use of high-quality simulated sky catalogs is essential for the success of cosmological surveys. The catalogs have diverse applications, such as investigating signatures of fun…
A Fundamental Test for Galaxy Formation Models: Matching the Lyman- Absorption Profiles of Galactic Halos over Three Decades in Distance
Daniele Sorini, José Oñorbe, Joseph F. Hennawi +1
Galaxy formation depends critically on the physical state of gas in the circumgalactic medium (CGM) and its interface with the intergalactic medium (IGM), determined by the complex…
A New Method to Measure the Post-Reionization Ionizing Background from the Joint Distribution of Lyman- and Lyman- Forest Transmission
Frederick B. Davies, Joseph F. Hennawi, Anna-Christina Eilers +1
The amplitude of the ionizing background that pervades the intergalactic medium (IGM) at the end of the epoch of reionization provides a valuable constraint on the emissivity of th…
Implications of Quasar Proximity Zones for the Epoch of Reionization and Quasar Lifetimes
Anna-Christina Eilers, Frederick B. Davies, Joseph F. Hennawi +3
We study quasar proximity zones in the redshift range by homogeneously analyzing medium resolution spectra, encompassing both archival and newly obtain…
The DESI Experiment Part I: Science,Targeting, and Survey Design
DESI Collaboration, Amir Aghamousa, Jessica Aguilar +290
DESI (Dark Energy Spectroscopic Instrument) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations (BAO) and the growth of structure through…
Self-Consistent Modeling of Reionization in Cosmological Hydrodynamical Simulations
Jose Oñorbe, Joseph F Hennawi, Zarija Lukić
The ultraviolet background (UVB) emitted by quasars and galaxies governs the ionization and thermal state of the intergalactic medium (IGM), regulates the formation of high-redshif…
Modeling the Lyman-alpha Forest in Collisionless Simulations
Daniele Sorini, José Oñorbe, Zarija Lukić +1
Cosmological hydrodynamic simulations can accurately predict the properties of the intergalactic medium (IGM), but only under the condition of retaining high spatial resolution nec…
A new method for imaging nuclear threats using cosmic ray muons
C. L. Morris, Jeffrey Bacon, Konstantin Borozdin +10
Muon tomography is a technique that uses cosmic ray muons to generate three dimensional images of volumes using information contained in the Coulomb scattering of the muons. Advant…
Nyx: A Massively Parallel AMR Code for Computational Cosmology
Ann Almgren, John Bell, Mike Lijewski +2
We present a new N-body and gas dynamics code, called Nyx, for large-scale cosmological simulations. Nyx follows the temporal evolution of a system of discrete dark matter particle…
Obtaining material identification with cosmic ray radiography
Christopher Morris, Konstantin Borozdin, Jeffrey Bacon +14
The passage of muons through matter is mostly affected by their Coulomb interactions with electrons and nuclei. The muon interactions with electrons lead to continuous energy loss…
Mass Function Predictions Beyond LCDM
Suman Bhattacharya, Katrin Heitmann, Martin White +3
The mass distribution of halos, as specified by the halo mass function, is a key input for several cosmological probes. The sizes of -body simulations are now such that, for the…
Galaxy Clusters as a probe of early dark energy
Ujjaini Alam, Zarija Lukić, Suman Bhattacharya
We study a class of early dark energy (EDE) models, in which, unlike in standard dark energy models, a substantial amount of dark energy exists in the matter-dominated era. We self…
The Structure of Halos: Implications for Group and Cluster Cosmology
Zarija Lukić, Darren Reed, Salman Habib +1
The dark matter halo mass function is a key repository of cosmological information over a wide range of mass scales, from individual galaxies to galaxy clusters. N-body simulations…