Search Publications
Vetting the "Lobster" Diagram: Searching for Unseen Companions in Wide Binaries Using NASA Space Exoplanet Missions
Hartman, Zachary D.; Lépine, Sébastien; Medan, Ilija
Over the past decade, the number of known wide-binary systems has expanded exponentially, thanks to the release of data from the Gaia Mission. Some of these wide-binary systems are actually higher-order multiples, where one of the components is an unresolved binary itself. One way to search for these systems is by identifying the overluminous comp…
Evidence for Parametric Decay Instability in the Lower Solar Atmosphere
Hahn, Michael; Fu, Xiangrong; Savin, Daniel Wolf
We find evidence for the first observation of the parametric decay instability (PDI) in the lower solar atmosphere. In particular, we find that the power spectrum of density fluctuations near the solar transition region resembles the power spectrum of the velocity fluctuations but with the frequency axis scaled up by about a factor of 2. These res…
2D and Slab Turbulent Cascade Rates in the Inner Heliosphere
Zank, G. P.; Zhao, L. -L.; Telloni, D. +1 more
We present a theoretical and observational study of 2D and slab turbulence cascade (or heating) rates of transverse total turbulence energies, transverse cross helicity, transverse outward and inward Elsässer energy, transverse fluctuating magnetic energy density, and transverse fluctuating kinetic energy from the perihelion of the first Parker So…
Near-infrared Spectroscopy of a Massive Young Stellar Object in the Direction toward the Galactic Center: XCN and Aromatic C-D Features
Onaka, Takashi; Sakon, Itsuki; Shimonishi, Takashi
We report near-infrared (2.5-5 µm) long-slit (~30″) spectroscopy of a young stellar object in the direction toward the Galactic center with the Infrared Camera on board the AKARI satellite. The present target is suggested to be AFGL 2006 based on its very red color and close location. The spectra show strong absorption features of H2
Circumnuclear Dust in AP Librae and the Source of Its VHE Emission
Georganopoulos, Markos; Breiding, Peter; Meyer, Eileen T. +2 more
The broad high-energy spectral component in blazars is usually attributed to various inverse Compton scattering processes in the relativistic jet, but has not been clearly identified in most cases due to degeneracies in physical models. AP Librae, a low-synchrotron-peaking BL Lac object (LBL) detected in 2015 by H.E.S.S. at very high energies (VHE…
The Role of Filamentary Structures in the Formation of Two Dense Cores, L1544 and L694-2
Caselli, Paola; Chung, Eun Jung; Kim, Shinyoung +5 more
We present mapping results of two prestellar cores, L1544 and L694-2, embedded in filamentary clouds in C18O (3-2), 13CO (3-2), 12CO (3-2), HCO+ (4-3), and H13CO+ (4-3) lines with the James Clerk Maxwell Telescope to examine the role of the filamentary structures in the formation of…
Luminous Optical and X-Ray Flaring of the Putative Redback Millisecond Pulsar 1FGL J0523.5-2529
Perez, Karen I.; Bogdanov, Slavko; Halpern, Jules P.
Several redback and black widow millisecond pulsar binaries have episodes of flaring in X-rays and optical. We initially detected such behavior from the Fermi selected redback candidate 1FGL J0523.5-2529 during optical time-series monitoring. Triggered observations with the Neil Gehrels Swift Observatory over the next ≈100 days showed episodic fla…
The Fast Evolving, Tremendous Blue Superoutburst in ASASSN-21au Reveals a Dichotomy in the Outbursts of Long-period AM CVns
Heinke, C. O.; Cavecchi, Y.; Vanmunster, T. +4 more
ASASSN-21au is an ultracompact accreting white dwarf binary (AM CVn type) with a period of ~58 minutes. Using multiwavelength observations of the system, we discovered a dichotomy in the behavior of outbursts in AM CVns. The binary showed an initial increase in brightness that lasted for at least 82 days, followed by an additional increase that la…
The Properties of Fast Yellow Pulsating Supergiants: FYPS Point the Way to Missing Red Supergiants
Davenport, James R. A.; Dorn-Wallenstein, Trevor Z.; Levesque, Emily M. +3 more
Fast yellow pulsating supergiants (FYPS) are a recently discovered class of evolved massive pulsators. As candidate supergiant objects, and one of the few classes of pulsating evolved massive stars, these objects have incredible potential to change our understanding of the structure and evolution of massive stars. Here we examine the lightcurves o…
Optical and Near-infrared Excesses are Correlated in T Tauri Stars
Kraus, Adam L.; Sullivan, Kendall
Accretion is one of the defining characteristics of classical T Tauri stars, fueled by the presence of a circumstellar disk comprised of dust and gas. Accretion produces a UV and optical excess, while re-radiated emission at the inner edge of the dust component of the disk produces a near-infrared (NIR) excess. The interplay between stars and thei…