Search Publications

AGN STORM 2. VI. Mapping Temperature Fluctuations in the Accretion Disk of Mrk 817
DOI: 10.3847/1538-4357/ad1386 Bibcode: 2024ApJ...961..219N

Gorjian, Varoujan; Kaspi, Shai; Hall, Patrick B. +49 more

We fit the UV/optical lightcurves of the Seyfert 1 galaxy Mrk 817 to produce maps of the accretion disk temperature fluctuations δ T resolved in time and radius. The δ T maps are dominated by coherent radial structures that move slowly (v ≪ c) inward and outward, which conflicts with the idea that disk variability is driven only by reverberation. …

2024 The Astrophysical Journal
eHST 9
Revealing the chemical structure of the Magellanic Clouds with APOGEE. I. Calculating individual stellar ages of RGB stars in the Large Magellanic Cloud
DOI: 10.1093/mnras/stae1949 Bibcode: 2024MNRAS.533.3685P

Choi, Yumi; Cunha, Katia; Smith, Verne V. +12 more

Stellar ages are critical for understanding the temporal evolution of a galaxy. We calculate the ages of over 6000 red giant branch stars in the Large Magellanic Cloud (LMC) observed with SDSS-IV / APOGEE-S. Ages are derived using multiband photometry, spectroscopic parameters ($\rm T_{eff}$

2024 Monthly Notices of the Royal Astronomical Society
Gaia 9
The Pristine Inner Galaxy Survey (PIGS): IX. The largest detailed chemical analysis of very metal-poor stars in the Sagittarius dwarf galaxy
DOI: 10.1051/0004-6361/202450553 Bibcode: 2024A&A...689A.201S

Sestito, Federico; Martin, Nicolas F.; Kordopatis, Georges +16 more

The most metal-poor stars provide valuable insights into the early chemical enrichment history of a system, carrying the chemical imprints of the first generations of supernovae. The most metal-poor region of the Sagittarius dwarf galaxy remains inadequately observed and characterised. To date, only ∼4 stars with [Fe/H] < ‑2.0 have been chemica…

2024 Astronomy and Astrophysics
Gaia 9
Probing the Heights and Depths of Y Dwarf Atmospheres: A Retrieval Analysis of the JWST Spectral Energy Distribution of WISE J035934.06–540154.6
DOI: 10.3847/1538-4357/ad583b Bibcode: 2024ApJ...971..121K

Cushing, Michael C.; Kirkpatrick, J. Davy; Marley, Mark S. +5 more

We present an atmospheric retrieval analysis of the Y0 brown dwarf WISE J035934.06‑540154.6 using the low-resolution 0.96–12 µm James Webb Space Telescope (JWST) spectrum presented in Beiler et al. We obtain volume number mixing ratios of the major gas-phase absorbers (H2O, CH4, CO, CO2, PH3, and H…

2024 The Astrophysical Journal
JWST 9
Unveiling the internal structure and formation history of the three planets transiting HIP 29442 (TOI-469) with CHEOPS
DOI: 10.1051/0004-6361/202450472 Bibcode: 2024A&A...688A.223E

Alonso, R.; Deleuil, M.; Erikson, A. +91 more

Multiplanetary systems spanning the radius valley are ideal testing grounds for exploring the different proposed explanations for the observed bimodality in the radius distribution of close-in exoplanets. One such system is HIP 29442 (TOI-469), an evolved K0V star hosting two super-Earths and one sub-Neptune. We observed HIP 29442 with CHEOPS for …

2024 Astronomy and Astrophysics
CHEOPS 9
Serendipitous detection of the dusty Type IIL SN 1980K with JWST/MIRI
DOI: 10.1093/mnras/stae507 Bibcode: 2024MNRAS.529..155Z

Temim, Tea; Van Dyk, Schuyler D.; Filippenko, Alexei V. +39 more

We present mid-infrared (mid-IR) imaging of the Type IIL supernova (SN) 1980K with the JWST more than 40 yr post-explosion. SN 1980K, located in the nearby (D ≈ 7 Mpc) 'SN factory' galaxy NGC 6946, was serendipitously captured in JWST/MIRI images taken of the field of SN 2004et in the same galaxy. SN 1980K serves as a promising candidate for study…

2024 Monthly Notices of the Royal Astronomical Society
eHST JWST 9
WTP 10aaauow: discovery of a new FU Ori outburst towards the RCW 49 star-forming region in NEOWISE data
DOI: 10.1093/mnras/stae953 Bibcode: 2024MNRAS.530.2076T

De, Kishalay; Hillenbrand, Lynne; Tran, Vinh

Large-amplitude accretion outbursts in young stars are expected to play a central role in protostellar assembly. Outburst identification historically has taken place using optical techniques, but recent, systematic infrared searches are enabling their discovery in heavily dust-obscured regions of the Galactic plane. Here, we present the discovery …

2024 Monthly Notices of the Royal Astronomical Society
Gaia 9
Strategies for Obtaining Robust Spectral Energy Distribution Fitting Parameters for Galaxies at z ∼ 1 and z ∼ 2 in the Absence of Infrared Data
DOI: 10.3847/1538-4357/ad17c8 Bibcode: 2024ApJ...962...59O

Salim, Samir; Osborne, Chandler

Robust estimation of star formation rates (SFRs) at higher redshifts (z ≳ 1) using UV–optical–near-infrared (NIR) photometry is contingent on the ability of spectral energy distribution (SED) fitting to constrain the dust attenuation, stellar metallicity, and star formation history (SFH) simultaneously. IR-derived dust luminosities can help break …

2024 The Astrophysical Journal
eHST 9
Discovery of Optically Emitting Circumgalactic Nebulae around the Majority of UV-luminous Quasars at Intermediate Redshift
DOI: 10.3847/1538-4357/ad3911 Bibcode: 2024ApJ...966..218J

Contini, Thierry; Johnson, Sean D.; Petitjean, Patrick +15 more

We report the discovery of large, ionized, [O II]-emitting circumgalactic nebulae around the majority of 30 UV-luminous quasars at z = 0.4–1.4 observed with deep, wide-field integral field spectroscopy with the Multi-Unit Spectroscopy Explorer (MUSE) by the Cosmic Ultraviolet Baryon Survey and MUSE Quasar Blind Emitters Survey. Among the 30 quasar…

2024 The Astrophysical Journal
Gaia 9
PHANGS-ML: Dissecting Multiphase Gas and Dust in Nearby Galaxies Using Machine Learning
DOI: 10.3847/1538-4357/ad39e5 Bibcode: 2024ApJ...968...24B

Sandstrom, Karin M.; Leroy, Adam K.; Rosolowsky, Erik +25 more

The PHANGS survey uses Atacama Large Millimeter/submillimeter Array, Hubble Space Telescope, Very Large Telescope, and JWST to obtain an unprecedented high-resolution view of nearby galaxies, covering millions of spatially independent regions. The high dimensionality of such a diverse multiwavelength data set makes it challenging to identify new t…

2024 The Astrophysical Journal
Gaia eHST JWST 9