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Medium Bands, Mega Science: A JWST/NIRCam Medium-band Imaging Survey of A2744
Maseda, Michael V.; Franx, Marijn; Muzzin, Adam +40 more
In this paper, we describe the "Medium Bands, Mega Science" JWST Cycle 2 survey (JWST-GO-4111) and demonstrate the power of these data to reveal both the spatially integrated and spatially resolved properties of galaxies from the local Universe to the era of cosmic dawn. Executed in 2023 November, MegaScience obtained ∼30 arcmin2 of dee…
Quasi-periodic X-ray eruptions years after a nearby tidal disruption event
Berger, E.; Angus, C. R.; Dhillon, V. S. +61 more
Quasi-periodic eruptions (QPEs) are luminous bursts of soft X-rays from the nuclei of galaxies, repeating on timescales of hours to weeks1–5. The mechanism behind these rare systems is uncertain, but most theories involve accretion disks around supermassive black holes (SMBHs) undergoing instabilities6–8 or interacting with a…
The Discovery of the Faintest Known Milky Way Satellite Using UNIONS
Smith, Simon E. T.; Cerny, William; Hayes, Christian R. +14 more
We present the discovery of Ursa Major III/UNIONS 1, the least luminous known satellite of the Milky Way, which is estimated to have an absolute V-band magnitude of $+{2.2}_{-0.3}^{+0.4}$ mag, equivalent to a total stellar mass of ${16}_{-5}^{+6}$ M ⊙. Ursa Major III/UNIONS 1 was uncovered in the deep, wide-field Ultraviolet Near Infrar…
EIGER. VI. The Correlation Function, Host Halo Mass, and Duty Cycle of Luminous Quasars at z ≳ 6
Hennawi, Joseph F.; Simcoe, Robert A.; Naidu, Rohan P. +13 more
We expect luminous (M 1450 ≲ ‑26.5) high-redshift quasars to trace the highest-density peaks in the early Universe. Here, we present observations of four z ≳ 6 quasar fields using JWST/NIRCam in the imaging and wide-field slitless spectroscopy mode and report a wide range in the number of detected [O III]-emitting galaxies in the quasar…
Widespread Rapid Quenching at Cosmic Noon Revealed by JWST Deep Spectroscopy
Conroy, Charlie; Johnson, Benjamin D.; Belli, Sirio +16 more
Massive quiescent galaxies in the young Universe are expected to be quenched rapidly, but it is unclear whether they all experience starbursts before quenching and what physical mechanism drives rapid quenching. We study 14 massive quiescent galaxies (
JADES - the Rosetta stone of JWST-discovered AGN: deciphering the intriguing nature of early AGN
Pérez-González, Pablo G.; Charlot, Stéphane; Parlanti, Eleonora +23 more
JWST has discovered a large population of active galactic nuclei (AGN) at high redshift, which are weak in the X-rays. Here we present the NIRSpec spectrum of the most extreme of these objects, GN-28074, an AGN at
Characterization of JWST NIRCam PSFs and Implications for AGN+host Image Decomposition
Shen, Yue; Zhuang, Ming-Yang
We present a detailed analysis of the point-spread function (PSF) of JWST NIRCam imaging in eight filters: F070W, F115W, F150W, F200W, F277W, F356W, F444W, and F480M, using publicly available data. Spatial variations in the PSF FWHM generally decrease with wavelength: the maximum and rms fractional variations are ∼20% and 5% in F070W, reduced to ∼…
New AGN diagnostic diagrams based on the [OIII]λ4363 auroral line
Feltre, Anna; Übler, Hannah; D'Eugenio, Francesco +8 more
The James Webb Space Telescope (JWST) is revolutionizing our understanding of black hole formation and growth in the early Universe. However, JWST has also revealed that some of the classical diagnostics, such as the Baldwin, Phillips & Terlevich (BPT) diagrams and X-ray emission, often fail to identify active galactic nuclei (AGN) at high red…
The progenitor star of SN 2023ixf: a massive red supergiant with enhanced, episodic pre-supernova mass loss
Sollerman, Jesper; Perley, Daniel A.; Fremling, Christoffer +10 more
We identify the progenitor star of SN 2023ixf in Messier 101 using Keck/NIRC2 adaptive optics imaging and pre-explosion Hubble Space Telescope (HST)/Advanced Camera for Surveys (ACS) images. The supernova, localized with diffraction spikes and high-precision astrometry, unambiguously coincides with a progenitor candidate of
Negative cosmological constant in the dark energy sector: tests from JWST photometric and spectroscopic observations of high-redshift galaxies
Menci, Nicola; Sen, Anjan A.; Vagnozzi, Sunny +2 more
Early observations with the James Webb Space Telescope (JWST) have revealed the existence of an unexpectedly large abundance of extremely massive galaxies at redshifts z ≳ 5: these are in tension with the predictions not only of the standard ΛCDM cosmology, but also with those of a wide class of dynamical dark energy (DE) models, and are generally…