Search Publications
Observational Constraints on the Physical Properties of Interstellar Dust in the Post-Planck Era
Draine, B. T.; Hensley, Brandon S.
We present a synthesis of the astronomical observations constraining the wavelength-dependent extinction, emission, and polarization from interstellar dust from UV to microwave wavelengths on diffuse Galactic sight lines. Representative solid-phase abundances for those sight lines are also derived. Given the sensitive new observations of polarized…
The Detection of a Hot Molecular Core in the Extreme Outer Galaxy
Shimonishi, Takashi; Furuya, Kenji; Izumi, Natsuko +1 more
Interstellar chemistry in low-metallicity environments is crucial to understand chemical processes in the past metal-poor universe. Recent studies of interstellar molecules in nearby low-metallicity galaxies have suggested that metallicity has a significant effect on the chemistry of star-forming cores. Here we report the first detection of a hot …
A New Sample of Warm Extreme Debris Disks from the ALLWISE Catalog
Henning, Thomas; Pál, András; Kinemuchi, Karen +12 more
Extreme debris disks (EDDs) are rare systems with peculiarly large amounts of warm dust that may stem from recent giant impacts between planetary embryos during the final phases of terrestrial planet growth. Here we report on the identification and characterization of six new EDDs. These disks surround F5-G9 type main-sequence stars with ages >…
Tracing PAH Size in Prominent Nearby Mid-Infrared Environments
Tielens, A. G. G. M.; Peeters, E.; Vacca, W. D. +2 more
We present observations from the First Light Infrared TEst CAMera (FLITECAM) on board the Stratospheric Observatory for Infrared Astronomy, the Spitzer Infrared Array Camera (IRAC), and the Spitzer Infrared Spectrograph SH mode in three well-known photodissociation regions, the reflection nebulae (RNe) NGC 7023 and NGC 2023 and to the southeast of…
The Dusty Heart of NGC 4151 Revealed by λ ∼ 1-40 µm Reverberation Mapping and Variability: A Challenge to Current Clumpy Torus Models
Lyu, Jianwei; Rieke, George H.
We probe the dusty environment of the archetypical Type 1 active galactic nucleus (AGN) in NGC 4151 with comprehensive IR reverberation mapping over several decades, in the J (∼1.22 µm), H (∼1.63 µm), K (∼2.19 µm), L (∼3.45 µm), and N bands (∼10.6 µm), plus multiple measurements at 20-40 µm. At 1-4 µm, the…
The Be Star 66 Ophiuchi: 60 Years of Disk Evolution
Carciofi, A. C.; Mota, B. C.; Jones, C. E. +5 more
We use a time-dependent hydrodynamic code and a non-LTE Monte Carlo code to model disk dissipation for the Be star 66 Ophiuchi. We compiled 63 years of observations from 1957 to 2020 to encompass the complete history of the growth and subsequent dissipation of the star's disk. Our models are constrained by new and archival photometry, spectroscopy…
The Atacama Cosmology Telescope: A Search for Planet 9
Hasselfield, Matthew; Sifón, Cristóbal; Aiola, Simone +37 more
We use Atacama Cosmology Telescope (ACT) observations at 98 GHz (2015-2019), 150 GHz (2013-2019), and 229 GHz (2017-2019) to perform a blind shift-and-stack search for Planet 9. The search explores distances from 300 au to 2000 au and velocities up to 6.'3 per year, depending on the distance (r). For a 5 Earth-mass Planet 9 the detection limit var…
The Thermal Sunyaev-Zel'dovich Effect from Massive, Quiescent 0.5 ≤ z ≤ 1.5 Galaxies
Cohen, Seth; Scannapieco, Evan; Mauskopf, Philip +5 more
We use combined South Pole Telescope (SPT)+Planck temperature maps to analyze the circumgalactic medium (CGM) encompassing 138,235 massive, quiescent 0.5 ≤ z ≤ 1.5 galaxies selected from data from the Dark Energy Survey (DES) and Wide-Field Infrared Survey Explorer (WISE). Images centered on these galaxies were cut from the 1.85 arcmin resolution …
Regulating Star Formation in Nearby Dusty Galaxies: Low Photoelectric Efficiencies in the Most Compact Systems
Inami, H.; Pope, A.; Armus, L. +5 more
Star formation in galaxies is regulated by heating and cooling in the interstellar medium (ISM). In particular, the processing of molecular gas into stars will depend strongly on the ratio of gas heating to gas cooling in the neutral gas around sites of recent star formation. In this work, we combine mid-infrared (mid-IR) observations of polycycli…
Discovery of an Edge-on Circumstellar Debris Disk around BD+45° 598: A Newly Identified Member of the β Pictoris Moving Group
Mamajek, Eric; Hinkley, Sasha; Matthews, Brenda +25 more
We report the discovery of a circumstellar debris disk viewed nearly edge-on and associated with the young, K1 star BD+45° 598 using high-contrast imaging at 2.2 µm obtained at the W.M. Keck Observatory. We detect the disk in scattered light with a peak significance of ∼5σ over three epochs, and our best-fit model of the disk is an almost ed…