Search Publications
A Possible Correlation between Metallicity and Near-IR Color for Late-M and L Dwarfs
Liu, Michael C.; Zhang, Zhoujian; Zhang, Ruihan
We examine the relationship between metallicity and J - K color for 64 benchmark late-M and L dwarfs, all of which are wide companions to higher-mass stars, and six of which are new discoveries. We assess the correlation between the Δ(J - K) color anomaly (the difference in an object's J - K color from the median color for field objects of the sam…
On the Heating of the Slow Solar Wind by Imbalanced Alfvén-wave Turbulence from 0.06 to 1 au: Parker Solar Probe and Solar Orbiter Observations
Halekas, Jasper S.; Bourouaine, Sofiane; Perez, Jean C. +3 more
In this work we analyze plasma and magnetic field data provided by the Parker Solar Probe and Solar Orbiter missions to investigate the radial evolution of the heating of Alfvénic slow wind by imbalanced Alfvén-wave (AW) turbulent fluctuations from 0.06 to 1 au. in our analysis we focus on slow solar-wind intervals with highly imbalanced and incom…
Probing Disk Ice Content and Polycyclic Aromatic Hydrocarbon Emission through Multiband MagAO+Clio Images of HD 141569
Weinberger, Alycia J.; Close, Laird M.; Males, Jared R. +4 more
We present resolved images of the inner disk component around HD 141569A using the Magellan adaptive optics system with the Clio2 1-5 µm camera, offering a glimpse of a complex system thought to be in a short evolutionary phase between protoplanetary and debris disk stages. We use a reference star along with the Karhunen-Loéve image projecti…
A Catalog of Pulsar X-Ray Filaments
Romani, Roger W.; Dinsmore, Jack T.
We present the first Chandra X-ray Observatory (CXO) catalog of "pulsar X-ray filaments," or "misaligned outflows." These are linear, synchrotron-radiating features powered by ultrarelativistic electrons and positrons that escape from bow shock pulsars. The filaments are misaligned with the (large) pulsar velocity, distinguishing them from the pul…
3He and Fe Spectral Properties in 3He-rich Solar Energetic Particle Events
Rodríguez-Pacheco, J.; Wimmer-Schweingruber, R. F.; Allen, R. C. +4 more
We have surveyed 3He-rich events on the Solar Orbiter mission from 2020 April to 2024 April, selecting isolated injections whose rollover 3He spectral shape is presumed to represent the initial acceleration state, unprocessed by subsequent activity such as coronal mass ejections or jets. A main goal has been to find relations…
ALMA-LEGUS. I. The Influence of Galaxy Morphology on Molecular Cloud Properties
Grebel, Eva K.; Smith, Linda J.; Aloisi, Alessandra +24 more
We present a comparative study of the molecular gas in two galaxies from the Legacy ExtraGalactic UV Survey (LEGUS) sample: barred spiral NGC 1313 and flocculent spiral NGC 7793. These two galaxies have similar masses, metallicities, and star formation rates, but NGC 1313 is forming significantly more massive star clusters than NGC 7793, especiall…
Circumnuclear Dust in Luminous Early-type Galaxies. I. Sample Properties and Stellar Luminosity Models
Ho, Luis C.; Barth, Aaron J.; Buote, David A. +8 more
Dusty circumnuclear disks (CNDs) in luminous early-type galaxies (ETGs) show regular, dynamically cold molecular gas kinematics. For a growing number of ETGs, Atacama Large Millimeter/sub-millimeter Array (ALMA) CO imaging and detailed gas-dynamical modeling facilitate moderate-to-high precision black hole (BH) mass (M BH) determination…
Dynamical Masses for the Hyades Binary System vB 120
Torres, Guillermo; Latham, David W.; Stefanik, Robert P.
We report spectroscopic observations of vB 120 (HD 30712), a 5.7 yr astrometric-spectroscopic binary system in the Hyades cluster. We combine our radial velocities with others from the literature, and with existing speckle interferometry measurements, to derive an improved 3D orbit for the system. We infer component masses of M 1 = 1.06…
Exploration of Halo Substructures in Integrals-of-motion Space with Gaia Data Release 3
Ye, Dashuang; Du, Cuihua; Deng, Mingji +2 more
Using kinematic data from the Gaia Data Release 3 catalog, along with metallicity estimates robustly derived from Gaia BP/RP spectra, we have explored the Galactic stellar halo in search of both known and potentially new substructures. By applying the Hierarchical Density-Based Spatial Clustering of Applications with Noise clustering algorithm in …
XMM–NuSTAR Observation and Multiwavelength Spectral Energy Distribution Modeling of Blazar 4FGL J1520.8–0348
Ajello, M.; Tramacere, A.; Marcotulli, L. +1 more
Active galactic nuclei (AGNs) can power relativistic jets, which are called blazars when pointed close to our line of sight. Depending on the presence or absence of emission lines in their optical spectra, blazars are categorized into flat spectrum radio quasars (FSRQs) or BL Lacertae (BL Lac) objects. According to the "blazar sequence," as synchr…