Search Publications
Was There a 3.5 keV Line?
Safdi, Benjamin R.; Foster, Joshua W.; Dessert, Christopher +1 more
The 3.5 keV line is a purported emission line observed in galaxies, galaxy clusters, and the Milky Way whose origin is inconsistent with known atomic transitions and has previously been suggested to arise from dark matter decay. We systematically reexamine the bulk of the evidence for the 3.5 keV line, attempting to reproduce six previous analyses…
A JWST/MIRI and NIRCam Analysis of the Young Stellar Object Population in the Spitzer I Region of NGC 6822
Temim, Tea; Hirschauer, Alec S.; Boyer, Martha L. +8 more
We present an imaging survey of the Spitzer I star-forming region in NGC 6822 conducted with the NIRCam and MIRI instruments on board JWST. Located at a distance of 490 kpc, NGC 6822 is the nearest non-interacting low-metallicity (∼0.2 Z ⊙) dwarf galaxy. It hosts some of the brightest known H II regions in the local universe, including …
[X/Fe] Marks the Spot: Mapping Chemical Azimuthal Variations in the Galactic Disk with APOGEE
Laporte, Chervin F. P.; Price-Whelan, Adrian M.; Horta, Danny +4 more
Chemical cartography of the Galactic disk provides insights into its structure and assembly history over cosmic time. In this work, we use chemical cartography to explore chemical gradients and azimuthal substructure in the Milky Way disk with giant stars from Apache Point Observatory Galactic Evolution Experiment (APOGEE) DR17. We confirm the exi…
Magnetic Fields in the Central Molecular Zone Influenced by Feedback and Weakly Correlated with Star Formation
Hasegawa, Tetsuo; Gu, Qilao; Liu, Tie +12 more
Magnetic fields of molecular clouds in the central molecular zone (CMZ) have been relatively under-observed at sub-parsec resolution. Here, we report JCMT/POL2 observations of polarized dust emission in the CMZ, which reveal magnetic field structures in dense gas at ∼0.5 pc resolution. The 11 molecular clouds in our sample include two in the weste…
A 2.9 hr Periodic Radio Transient with an Optical Counterpart
Strader, Jay; Rea, N.; Chomiuk, Laura +12 more
We present a long-period radio transient (GLEAM-X J0704‑37) discovered to have an optical counterpart, consistent with a cool main-sequence star of spectral type M3. The radio periodicity occurs at the longest period yet found, 2.9 hr, and was discovered in archival low-frequency data from the Murchison Widefield Array. High time resolution observ…
The Heavy Metal Survey: Star Formation Constraints and Dynamical Masses of 21 Massive Quiescent Galaxies at z = 1.3–2.3
Barro, Guillermo; Franx, Marijn; van Dokkum, Pieter +14 more
In this paper, we present the Heavy Metal Survey, which obtained ultradeep medium-resolution spectra of 21 massive quiescent galaxies at 1.3 < z < 2.3 with Keck/LRIS and MOSFIRE. With integration times of up to 16 hr per band per galaxy, we observe numerous Balmer and metal absorption lines in atmospheric windows. We successfully derive spec…
Possible Carbon Dioxide above the Thick Aerosols of GJ 1214 b
Fortney, Jonathan J.; Wheatley, Peter J.; Henry, Gregory W. +14 more
Sub-Neptune planets with radii smaller than Neptune (3.9 R ⊕) are the most common type of planet known to exist in the Milky Way, even though they are absent in the solar system. These planets can potentially have a large diversity of compositions as a result of different mixtures of rocky material, icy material, and gas accreted from a…
Characterizing the Average Interstellar Medium Conditions of Galaxies at z ∼ 5.6–9 with Ultraviolet and Optical Nebular Lines
Papovich, Casey; Cole, Justin W.; Finkelstein, Steven L. +30 more
Ultraviolet (UV; rest-frame ∼1200–2000 Å) spectra provide a wealth of diagnostics to characterize fundamental galaxy properties, such as their chemical enrichment, the nature of their stellar populations, and their amount of Lyman-continuum (LyC) radiation. In this work, we leverage publicly released JWST data to construct the rest-frame UV-to-opt…
The Search for Failed Supernovae with the Large Binocular Telescope: The Mid-infrared Counterpart to N6946-BH1
Kochanek, Christopher S.; Neustadt, Jack M. M.; Stanek, Krzysztof Z.
We present JWST MIRI 5.6, 10, and 21 µm observations of the candidate failed supernova N6946-BH1 along with Hubble Space Telescope (HST) WFPC/IR 1.1 and 1.6 µm data and ongoing optical monitoring data with the Large Binocular Telescope. There is a very red, dusty source at the location of the candidate, which has only ∼10%–15% of the l…
A Census from JWST of Extreme Emission-line Galaxies Spanning the Epoch of Reionization in CEERS
Papovich, Casey; Finkelstein, Steven L.; Barro, Guillermo +30 more
We present a sample of 1165 extreme emission-line galaxies (EELGs) at 4 < z < 9 selected using James Webb Space Telescope (JWST) NIRCam photometry in the Cosmic Evolution Early Release Science (CEERS) program. We use a simple method to photometrically identify EELGs with Hβ + [O III] (combined) or Hα emission of observed-frame equivalent wid…