Search Publications
The UNCOVER Survey: A First-look HST + JWST Catalog of 60,000 Galaxies near A2744 and beyond
Papovich, Casey; Maseda, Michael V.; Franx, Marijn +43 more
In 2022 November, the James Webb Space Telescope (JWST) returned deep near-infrared images of A2744-a powerful lensing cluster capable of magnifying distant, incipient galaxies beyond it. Together with existing Hubble Space Telescope (HST) imaging, this publicly available data set opens a fundamentally new discovery space to understand the remaini…
The Initial Mass Function Based on the Full-sky 20 pc Census of ∼3600 Stars and Brown Dwarfs
Tsai, Chao-Wei; Mamajek, Eric; Gonzales, Eileen C. +83 more
A complete accounting of nearby objects—from the highest-mass white dwarf progenitors down to low-mass brown dwarfs—is now possible, thanks to an almost complete set of trigonometric parallax determinations from Gaia, ground-based surveys, and Spitzer follow-up. We create a census of objects within a Sun-centered sphere of 20 pc radius and check p…
The Chandra Source Catalog Release 2 Series
Azadi, Mojegan; Lauer, Jennifer; Fabbiano, Giuseppina +17 more
The Chandra Source Catalog (CSC) is a virtual X-ray astrophysics facility that enables both detailed individual source studies and statistical studies of large samples of X-ray sources detected in Advanced CCD Imaging Spectrometer and High Resolution Camera-I imaging observations obtained by the Chandra X-ray Observatory. The catalog provides care…
AspGap: Augmented Stellar Parameters and Abundances for 37 Million Red Giant Branch Stars from Gaia XP Low-resolution Spectra
Hogg, David W.; Li, Jiadong; Rix, Hans-Walter +2 more
We present AspGap, a new approach to inferring stellar labels from the low-resolution Gaia XP spectra, including precise [α/M] estimates—the first time these are obtained by such an approach. AspGap is a neural-network-based regression model trained on APOGEE spectra. In the training step, AspGap learns to use not only XP spectra to predict stella…
TREASUREHUNT: Transients and Variability Discovered with HST in the JWST North Ecliptic Pole Time-domain Field
Im, M.; Ryan, R. E.; Grogin, Norman A. +56 more
The James Webb Space Telescope (JWST) North Ecliptic Pole (NEP) Time-domain Field (TDF) is a >14' diameter field optimized for multiwavelength time-domain science with JWST. It has been observed across the electromagnetic spectrum both from the ground and from space, including with the Hubble Space Telescope (HST). As part of HST observations o…
A Comprehensive Correction of the Gaia DR3 XP Spectra
Xiang, Maosheng; Huang, Yang; Niu, Zexi +7 more
By combining spectra from the CALSPEC and NGSL, as well as spectroscopic data from the LAMOST Data Release 7 (DR7), we have analyzed and corrected the systematic errors of the Gaia DR3 BP/RP (XP) spectra. The errors depend on the normalized spectral energy distribution (simplified by two independent "colors") and G magnitude. Our corrections are a…
Setting the Stage for the Search for Life with the Habitable Worlds Observatory: Properties of 164 Promising Planet-survey Targets
Kane, Stephen R.; Dressing, Courtney D.; Harada, Caleb K. +1 more
The Decadal Survey on Astronomy and Astrophysics 2020 has recommended that NASA realize a large IR/optical/UV space telescope optimized for high-contrast imaging and spectroscopy of ∼25 exo-Earths and transformative general astrophysics. The NASA Exoplanet Exploration Program (ExEP) has subsequently released a list of 164 nearby (d < 25 pc) tar…
Ultradiffuse Galaxies—A Distinct Population? Dwarf Galaxies in the Coma Cluster and A262 from Deep u'–g'–r' Wendelstein Imaging Data
Bender, Ralf; Kluge, Matthias; Zöller, Raphael +1 more
In this study, we compare the structural parameters of ultradiffuse galaxies (UDGs) to those of other dwarf galaxies and investigate whether UDGs form a distinct population. We observed deep $u^{\prime} $ -, $g^{\prime} $ -, and $r^{\prime} $ -band images (maximum limiting surface brightness [3σ, 10″ × 10″] $u^{\prime} $ and $g^{\prime} $ : $\appr…
The MeerKAT Absorption Line Survey (MALS) Data Release. I. Stokes I Image Catalogs at 1–1.4 GHz
Momjian, E.; Combes, F.; Petitjean, P. +24 more
The MeerKAT Absorption Line Survey (MALS) has observed 391 telescope pointings at the L band (900–1670 MHz) at δ ≲ +20°. We present radio continuum images and a catalog of 495,325 (240,321) radio sources detected at a signal-to-noise ratio (S/N) > 5 over an area of 2289 deg2 (1132 deg2) at 1006 MHz (1381 MHz). Every MALS p…
Quantifying the Escape of Lyα at z ≈ 5–6: A Census of Lyα Escape Fraction with Hα-emitting Galaxies Spectroscopically Confirmed by JWST and VLT/MUSE
Chevallard, Jacopo; Fan, Xiaohui; Jiang, Linhua +11 more
The James Webb Space Telescope provides an unprecedented opportunity for unbiased surveys of Hα-emitting galaxies at z > 4 with the NIRCam's wide-field slitless spectroscopy (WFSS). In this work, we present a census of Lyα escape fraction (f esc,Lyα ) of 165 star-forming galaxies at z = 4.9–6.3, utilizing their Hα emission directly m…