Search Publications
New Coronae and Stellar Associations Revealed by a Clustering Analysis of the Solar Neighborhood
Faherty, Jacqueline K.; Gagné, Jonathan; Moranta, Leslie +1 more
We present the results of a density-based clustering analysis of the 6D XYZ Galactic positions and UVW-space velocities of nearby (≤200 pc) Gaia Early Data Release 3 stars with radial velocities using HDBSCAN, in opposition to previous studies (Kounkel & Covey 2019; Meingast et al. 2021) that only included positions and tangential velocities. …
The mystery of unidentified infrared emission bands
Kwok, Sun
A family of unidentified infrared emission (UIE) bands has been observed throughout the Universe. The current observed spectral properties of the UIE bands are summarized. These properties are discussed in the frameworks of different models of the chemical carriers of these bands. The UIE carriers represent a large reservoir of carbon in the Unive…
WO-type Wolf-Rayet Stars: The Last Hurrah of Massive Star Evolution
Aadland, Erin; Massey, Philip; Hillier, D. John +3 more
Are WO-type Wolf-Rayet (WR) stars in the final stage of massive star evolution before core-collapse? Although WC- and WO-type WRs have very similar spectra, WOs show a much stronger O VI λλ3811,34 emission-line feature. This has usually been interpreted to mean that WOs are more oxygen rich than WCs, and thus further evolved. However, previous stu…
The TESS-Keck Survey. VIII. Confirmation of a Transiting Giant Planet on an Eccentric 261 Day Orbit with the Automated Planet Finder Telescope
Gagliano, Robert; Kristiansen, Martti H.; LaCourse, Daryll M. +72 more
We report the discovery of TOI-2180 b, a 2.8 M J giant planet orbiting a slightly evolved G5 host star. This planet transited only once in Cycle 2 of the primary Transiting Exoplanet Survey Satellite (TESS) mission. Citizen scientists identified the 24 hr single-transit event shortly after the data were released, allowing a Doppler moni…
Constraining the Physical Properties of Stellar Coronal Mass Ejections with Coronal Dimming: Application to Far-ultraviolet Data of ϵ Eridani
Loyd, R. O. Parke; France, Kevin; Youngblood, Allison +9 more
Coronal mass ejections (CMEs) are a prominent contributor to solar system space weather and might have impacted the Sun's early angular momentum evolution. A signal diagnostic of CMEs on the Sun is coronal dimming: a drop in coronal emission, tied to the mass of the CME, that is the direct result of removing emitting plasma from the corona. We pre…
A New Method for Direct Measurement of Isotopologue Ratios in Protoplanetary Disks: A Case Study of the 12CO/13CO Ratio in the TW Hya Disk
Nomura, Hideko; Tsukagoshi, Takashi; Furuya, Kenji +2 more
Planetary systems are thought to be born in protoplanetary disks. Isotope ratios are a powerful tool for investigating the material origin and evolution from molecular clouds to planetary systems via protoplanetary disks. However, it is challenging to measure the isotope (isotopologue) ratios, especially in protoplanetary disks, because the emissi…
The First Near-infrared Transmission Spectrum of HIP 41378 f, A Low-mass Temperate Jovian World in a Multiplanet System
Kirk, James; López-Morales, Mercedes; Alam, Munazza K. +22 more
We present a near-infrared transmission spectrum of the long-period (P = 542 days), temperate (T eq = 294 K) giant planet HIP 41378 f obtained with the Wide-Field Camera 3 instrument aboard the Hubble Space Telescope (HST). With a measured mass of 12 ± 3 M ⊕ and a radius of 9.2 ± 0.1 R ⊕, HIP 41378 f has an extreme…
CME Evolution in the Structured Heliosphere and Effects at Earth and Mars During Solar Minimum
Nitta, Nariaki V.; Holmström, Mats; Futaana, Yoshifumi +13 more
The activity of the Sun alternates between a solar minimum and a solar maximum, the former corresponding to a period of "quieter" status of the heliosphere. During solar minimum, it is in principle more straightforward to follow eruptive events and solar wind structures from their birth at the Sun throughout their interplanetary journey. In this p…
A Census of Optically Dark Massive Galaxies in the Early Universe from Magnification by Lensing Galaxy Clusters
Kong, Xu; Zheng, Wei; Liu, Daizhong +10 more
We present ALMA 870 µm and JCMT/SCUBA2 850 µm dust continuum observations of a sample of optically dark and strongly lensed galaxies in cluster fields. The ALMA and SCUBA2 observations reach a median rms of ~0.11 mJy and 0.44 mJy, respectively, with the latter close to the confusion limit of the data at 850 µm. This represents on…
Detections of solar-like oscillations in dwarfs and subgiants with Kepler DR25 short-cadence data
García, R. A.; Mosser, B.; Mathur, S. +6 more
During the survey phase of the Kepler mission, several thousand stars were observed in short cadence, allowing for the detection of solar-like oscillations in more than 500 main-sequence and subgiant stars. These detections showed the power of asteroseismology in determining fundamental stellar parameters. However, the Kepler Science Office discov…