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Full-Text Articles in Physical Sciences and Mathematics

Uncover: Jwst Spectroscopy Of Three Cold Brown Dwarfs At Kiloparsec-Scale Distances, Sam E. Cutler, Et. Al. Jan 2024

Uncover: Jwst Spectroscopy Of Three Cold Brown Dwarfs At Kiloparsec-Scale Distances, Sam E. Cutler, Et. Al.

Astronomy Department Faculty Publication Series

We report JWST/NIRSpec spectra of three distant T-type brown dwarfs identified in the Ultradeep NIRSpec and NIRCam ObserVations before the Epoch of Reionization (UNCOVER) survey of the Abell 2744 lensing field. One source was previously reported as a candidate T dwarf on the basis of NIRCam photometry, while two sources were initially identified as candidate active galactic nuclei. Low-resolution 1–5 μm spectra confirm the presence of molecular features consistent with T dwarf atmospheres, and comparison to spectral standards infers classifications of sdT1, T6, and T8–T9. The warmest source, UNCOVER-BD-1, shows evidence of subsolar metallicity, and atmosphere model fits indicate …


X-Ray Detection Of The Most Extreme Star-Forming Galaxies At The Cosmic Noon Via Strong Lensing, Q Daniel Wang, Carlos Garcia Diaz, Min S. Yun, Et. Al. Jan 2024

X-Ray Detection Of The Most Extreme Star-Forming Galaxies At The Cosmic Noon Via Strong Lensing, Q Daniel Wang, Carlos Garcia Diaz, Min S. Yun, Et. Al.

Astronomy Department Faculty Publication Series

Hyperluminous infrared galaxies (HyLIRGs) are the most extreme star-forming systems observed in the early Universe, and their properties still elude comprehensive understanding. We have undertaken a large XMMNewton observing programme to probe the total accreting black hole population in three HyLIRGs at z = 2.12, 3.25, and 3.55, gravitationally lensed by foreground galaxies. Selected from the Planck All-Sky Survey to Analyse Gravitationally lensed Extreme Starbursts (PASSAGES), these HyLIRGs have apparent infrared luminosities >1014 L. Our observations revealed X-ray emission in each of them. PJ1336+49 appears to be dominated by high-mass X-ray binaries (HMXBs). Remarkably, the luminosity …


Alma-Legus. Ii. The Influence Of Subgalactic Environments On Molecular Cloud Properties, Daniela Calzetti, Et. Al. Jan 2024

Alma-Legus. Ii. The Influence Of Subgalactic Environments On Molecular Cloud Properties, Daniela Calzetti, Et. Al.

Astronomy Department Faculty Publication Series

We compare the molecular cloud properties in subgalactic regions of two galaxies, barred spiral NGC 1313, which is forming many massive clusters, and flocculent spiral NGC 7793, which is forming significantly fewer massive clusters despite having a similar star formation rate to NGC 1313. We find that there are larger variations in cloud properties between different regions within each galaxy than there are between the galaxies on a global scale, especially for NGC 1313. There are higher masses, line widths, pressures, and virial parameters in the arms of NGC 1313 and the center of NGC 7793 than in the interarm …


Uncover Spectroscopy Confirms The Surprising Ubiquity Of Active Galactic Nuclei In Red Sources At Z > 5, Sam E. Cutler, John R. Weaver, Katherine E. Whitaker, Et. Al. Jan 2024

Uncover Spectroscopy Confirms The Surprising Ubiquity Of Active Galactic Nuclei In Red Sources At Z > 5, Sam E. Cutler, John R. Weaver, Katherine E. Whitaker, Et. Al.

Astronomy Department Faculty Publication Series

The James Webb Space Telescope is revealing a new population of dust-reddened broad-line active galactic nuclei (AGN) at redshifts z ≳ 5. Here we present deep NIRSpec/Prism spectroscopy from the Cycle 1 Treasury program Ultradeep NIRSpec and NIRCam ObserVations before the Epoch of Reionization (UNCOVER) of 15 AGN candidates selected to be compact, with red continua in the rest-frame optical but with blue slopes in the UV. From NIRCam photometry alone, they could have been dominated by dusty star formation or an AGN. Here we show that the majority of the compact red sources in UNCOVER are dust-reddened AGN: 60% …