Search Publications
A Long Time Ago in a Galaxy Far, Far Away: A Candidate z ∼ 12 Galaxy in Early JWST CEERS Imaging
Papovich, Casey; Cole, Justin W.; Yang, Guang +119 more
We report the discovery of a candidate galaxy with a photo-z of z ~ 12 in the first epoch of the James Webb Space Telescope (JWST) Cosmic Evolution Early Release Science Survey. Following conservative selection criteria, we identify a source with a robust z phot = ${11.8}_{-0.2}^{+0.3}$ (1σ uncertainty) with m F200W = 27.3 an…
Early Results from GLASS-JWST. III. Galaxy Candidates at z 9-15
Santini, Paola; Calabrò, Antonello; Castellano, Marco +27 more
We present the results of a first search for galaxy candidates at z ~ 9-15 on deep seven-band NIRCam imaging acquired as part of the GLASS-James Webb Space Telescope (JWST) Early Release Science Program on a flanking field of the Frontier Fields cluster A2744. Candidates are selected via two different renditions of the Lyman-break technique, isola…
The JWST Early Release Observations
Koekemoer, Anton M.; Ravindranath, Swara; Henry, Alaina +34 more
The James Webb Space Telescope (JWST) Early Release Observations (EROs) is a set of public outreach products created to mark the end of commissioning and the beginning of science operations for JWST. Colloquially known as the "Webb First Images and Spectra," these products were intended to demonstrate to the worldwide public that JWST is ready for…
A Guide to Realistic Uncertainties on the Fundamental Properties of Solar-type Exoplanet Host Stars
van Saders, Jennifer; Huber, Daniel; Claytor, Zachary R. +1 more
Our understanding of the properties and demographics of exoplanets critically relies on our ability to determine the fundamental properties of their host stars. The advent of Gaia and large spectroscopic surveys has now made it possible, in principle, to infer the properties of individual stars, including most exoplanet hosts, to very high precisi…
On the Stellar Populations of Galaxies at z = 9-11: The Growth of Metals and Stellar Mass at Early Times
Papovich, Casey; Finkelstein, Steven L.; Dickinson, Mark +18 more
We present a detailed stellar population analysis of 11 bright (H < 26.6) galaxies at z = 9-11 (three spectroscopically confirmed) to constrain the chemical enrichment and growth of stellar mass of early galaxies. We use the flexible Bayesian spectral energy distribution (SED) fitting code Prospector with a range of star formation histories (SF…
An Isolated Stellar-mass Black Hole Detected through Astrometric Microlensing
Ferguson, Henry C.; Brown, Thomas M.; Casertano, Stefano +91 more
We report the first unambiguous detection and mass measurement of an isolated stellar-mass black hole (BH). We used the Hubble Space Telescope (HST) to carry out precise astrometry of the source star of the long-duration (t E ≃ 270 days), high-magnification microlensing event MOA-2011-BLG-191/OGLE-2011-BLG-0462 (hereafter designated as …
Fast, Slow, Early, Late: Quenching Massive Galaxies at z ∼ 0.8
Barro, Guillermo; van Dokkum, Pieter; Conroy, Charlie +14 more
We investigate the stellar populations for a sample of 161 massive, mainly quiescent galaxies at <z obs> = 0.8 with deep Keck/DEIMOS rest-frame optical spectroscopy (HALO7D survey). With the fully Bayesian framework Prospector, we simultaneously fit the spectroscopic and photometric data with an advanced physical model (including …
The Global Dynamical Atlas of the Milky Way Mergers: Constraints from Gaia EDR3-based Orbits of Globular Clusters, Stellar Streams, and Satellite Galaxies
Sharma, Sanjib; Malhan, Khyati; Ibata, Rodrigo A. +7 more
The Milky Way halo was predominantly formed by the merging of numerous progenitor galaxies. However, our knowledge of this process is still incomplete, especially in regard to the total number of mergers, their global dynamical properties and their contribution to the stellar population of the Galactic halo. Here, we uncover the Milky Way mergers …
The Low-redshift Lyman Continuum Survey. II. New Insights into LyC Diagnostics
Papovich, Casey; Finkelstein, Steven L.; Santini, Paola +43 more
The Lyman continuum (LyC) cannot be observed at the epoch of reionization (z ≳ 6) owing to intergalactic H I absorption. To identify LyC emitters (LCEs) and infer the fraction of escaping LyC, astronomers have developed various indirect diagnostics of LyC escape. Using measurements of the LyC from the Low-redshift Lyman Continuum Survey (LzLCS), w…
An Isolated Mass-gap Black Hole or Neutron Star Detected with Astrometric Microlensing
Lu, Jessica R.; Udalski, Andrzej; Mróz, Przemek +42 more
We present the analysis of five black hole candidates identified from gravitational microlensing surveys. Hubble Space Telescope astrometric data and densely sampled light curves from ground-based microlensing surveys are fit with a single-source, single-lens microlensing model in order to measure the mass and luminosity of each lens and determine…