Search Publications
The Geochemical Potential for Metabolic Processes on the Sub-Neptune Exoplanet K2-18b
Glein, Christopher R.
Quantifying disequilibria is important to understand whether an environment could be habitable. It has been proposed that the exoplanet K2-18b has a hydrogen-rich atmosphere and a water ocean, making it a "hycean world." The James Webb Space Telescope recently made measurements of methane, CO2, and possibly dimethyl sulfide (DMS) in the…
Atmospheric Retrievals Suggest the Presence of a Secondary Atmosphere and Possible Sulfur Species on L98-59 d from JWST Nirspec G395H Transmission Spectroscopy
Sing, David K.; Espinoza, Néstor; Crouzet, Nicolas +10 more
L 98-59 d is a Super-Earth planet orbiting an M-type star. We performed retrievals on the transmission spectrum of L 98-59 d obtained using NIRSpec G395H during a single transit, from JWST Cycle 1 GTO 1224. The wavelength range of this spectrum allows us to detect the presence of several atmospheric species. We found that the spectrum is consisten…
PROJECT-J: JWST Observations of HH46 IRS and Its Outflow. Overview and First Results
Hartigan, Patrick; Codella, Claudio; Alcalá, Juan M. +23 more
We present the first results of the JWST program PROJECT-J (PROtostellar JEts Cradle Tested with JWST), designed to study the Class I source HH46 IRS and its outflow through NIRSpec and MIRI spectroscopy (1.66–28 µm). The data provide line images (∼6.″6 in length with NIRSpec, and up to ∼20″ with MIRI) revealing unprecedented details within …
Dissecting the Crab Nebula with JWST: Pulsar Wind, Dusty Filaments, and Ni/Fe Abundance Constraints on the Explosion Mechanism
Temim, Tea; Drissen, Laurent; Rest, Armin +19 more
We present JWST observations of the Crab Nebula, the iconic remnant of the historical SN 1054. The observations include NIRCam and MIRI imaging mosaics plus MIRI/MRS spectra that probe two select locations within the ejecta filaments. We derive a high-resolution map of dust emission and show that the grains are concentrated in the innermost, high-…
What Are the Pillars of Reionization? Revising the AGN Luminosity Function at z ∼ 5
Bisigello, Laura; Grazian, Andrea; Boutsia, Konstantina +22 more
In the past, high-z active galactic nuclei (AGNs) were given a minor role as possible drivers of reionization, despite initial evidence in favor of their large space densities at low luminosities by Chandra and the Hubble Space Telescope. Recent observations from JWST are finding relatively large numbers of faint AGNs at z > 4, convincingly con…
JWST MIRI/Medium Resolution Spectrograph (MRS) Observations and Spectral Models of the Underluminous Type Ia Supernova 2022xkq
Suntzeff, N. B.; Wang, L.; Galbany, L. +44 more
We present a JWST mid-infrared (MIR) spectrum of the underluminous Type Ia Supernova (SN Ia) 2022xkq, obtained with the medium-resolution spectrometer on the Mid-Infrared Instrument (MIRI) ∼130 days post-explosion. We identify the first MIR lines beyond 14 µm in SN Ia observations. We find features unique to underluminous SNe Ia, including t…
The Web Epoch of Reionization Lyα Survey (WERLS). I. MOSFIRE Spectroscopy of z ∼ 7–8 Lyα Emitters
Papovich, Casey; Finkelstein, Steven L.; Casey, Caitlin M. +34 more
We present the first results from the Web Epoch of Reionization Lyα Survey (WERLS), a spectroscopic survey of Lyα emission using Keck I/MOSFIRE and LRIS. WERLS targets bright (J < 26) galaxy candidates with photometric redshifts of 5.5 ≲ z ≲ 8 selected from pre-JWST imaging embedded in the Epoch of Reionization (EoR) within three JWST deep fiel…
CANUCS: An Updated Mass and Magnification Model of A370 with JWST
Willott, Chris J.; Rihtaršič, Gregor; Bradač, Maruša +9 more
We present an updated mass and magnification model of galaxy cluster A370 using new NIRCam, NIRISS, and NIRSpec data from the Canadian NIRISS Unbiased Cluster Survey (CANUCS). Using Lenstool and a combination of archival Hubble Space Telescope (HST) and MUSE data with new JWST data as constraints, we derive an improved gravitational lensing model …
A Tale of Two Molecules: The Underprediction of CO2 and Overprediction of PH3 in Late T and Y Dwarf Atmospheric Models
Cushing, Michael C.; Kirkpatrick, J. Davy; Marley, Mark S. +5 more
The sensitivity and spectral coverage of JWST are enabling us to test our assumptions of ultracool dwarf atmospheric chemistry, especially with regards to the abundances of phosphine (PH3) and carbon dioxide (CO2). In this paper, we use Near Infrared Spectrograph PRISM spectra (∼0.8‑5.5 µm, R ∼ 100) of four late T and Y…
Orbital Torus Imaging: Acceleration, Density, and Dark Matter in the Galactic Disk Measured with Element Abundance Gradients
Hogg, David W.; Price-Whelan, Adrian M.; Ness, Melissa K. +5 more
Under the assumption of a simple and time-invariant gravitational potential, many Galactic dynamics techniques infer the milky Way's mass and dark matter distributions from stellar kinematic observations. These methods typically rely on parameterized potential models of the Galaxy and must take into account nontrivial survey selection effects, bec…