Search Publications
An Inward-moving and Asymmetric Velocity Wave Detected in LAMOST-Gaia
Zhao, Gang; Chen, Yuqin; Wu, Wenbo +3 more
The phase space, as coded by kinematic parameters and chemical abundances, is crucial for understanding the formation of the Galactic disk. Using red giant stars from the Galactic thin disk with [Fe/H] > - 0.8 and low-α ratios identified in LAMOST-Gaia, we detect numerous ridges and undulations in the R-V ϕ diagram coded by median …
A Multiwavelength Portrait of the 3C 220.3 Lensed System
Azadi, Mojegan; Wilkes, Belinda J.; Worrall, D. M. +10 more
The 3C 220.3 system is a rare case of a foreground narrow-line radio galaxy ("galaxy A," z A = 0.6850) lensing a background submillimeter galaxy (z SMG = 2.221). New spectra from MMT/Binospec confirm that the companion galaxy ("galaxy B") is part of the lensing system with z B = 0.6835. New three-color Hubble S…
Expansion Properties of the Young Supernova Type Iax Remnant Pa 30 Revealed
Kulkarni, S. R.; Raymond, John C.; Caiazzo, Ilaria +14 more
The recently discovered Pa 30 nebula, the putative type Iax supernova remnant associated with the historical supernova of 1181 AD, shows puzzling characteristics that make it unique among known supernova remnants. In particular, Pa 30 exhibits a complex morphology, with a unique radial and filamentary structure, and it hosts a hot stellar remnant …
Properties of Galactic B[e] Supergiants. X. Refined Orbit and Fundamental Parameters of the HD 327083 Binary System
Miroshnichenko, A. S.; Manset, N.; Zharikov, S. V. +5 more
HD 327083 is a binary system that consists of two supergiant components and exhibits the B[e] phenomenon. In this paper, we report the determination of a new set of the system's fundamental parameters using a combination of photometric and spectroscopic data as well as the Gaia EDR3 distance. We found that the orbital period of the system is 107.6…
Visual Orbits of Wolf–Rayet Stars. II. The Orbit of the Nitrogen-rich Wolf–Rayet Binary WR 138 Measured with the CHARA Array
Moffat, Anthony F. J.; Monnier, John D.; Schaefer, Gail H. +19 more
Classical Wolf–Rayet (WR) stars are descendants of massive OB-type stars that have lost their hydrogen-rich envelopes and are in the final stages of stellar evolution, possibly exploding as Type Ib/c supernovae. It is understood that the mechanisms driving this mass loss are either strong stellar winds and or binary interactions, so intense studie…
Exploration of a Dissolving Association Made Up of IC 2602, Tucana–Horologium, and Other Young Comoving Groups
Kiman, Rocio; Faherty, Jacqueline K.; Gagné, Jonathan +11 more
Recently Gagné et al. suggested that young moving groups with similar kinematic properties could be part of larger dissolving structures. One example was IC 2602 as the core of a group of associations, including its corona (CIC 2602), Tucana-Horologium (THA), and parts of Theia 92. We explore this hypothesis by measuring the rotation periods of 95…
The Diffusion Tensor of Protons at 1 au: Comparing Simulation, Observation, and Theory
Engelbrecht, N. E.; Strauss, R. D.; Lang, J. T. +1 more
The natural variation in plasma parameters observed at 1 au can lead to a variation in transport parameters, such as diffusion and drift coefficients, for energetic charged particles of solar and galactic origin. Given the importance of these parameters to particle transport studies, this variation is investigated through test particle simulations…
Helioseismic Properties of Dynamo Waves in the Variation of Solar Differential Rotation
Kosovichev, Alexander G.; Mandal, Krishnendu; Pipin, Valery V.
Solar differential rotation exhibits a prominent feature: its cyclic variations over the solar cycle, referred to as zonal flows or torsional oscillations, are observed throughout the convection zone. Given the challenge of measuring magnetic fields in subsurface layers, understanding deep torsional oscillations becomes pivotal in deciphering the …
On the Possible Mechanisms of the SEP Event and Electron Enhancement over the SEP Decay Phase on 2023 August 5
Gan, W. Q.; Li, Y. P.; Firoz, Kazi A.
We carry out this study on the solar energetic particle (SEP) event that occurred on 2023 August 5 over the ascending phase of the current solar cycle 25. It is found that the SEP event might have been initiated by the M1.6 flare, while the SEP peak was caused by the coronal shock manifested in DH-type II radio burst over the propagation phase of …
An In-depth Analysis of Quiet-Sun IRIS Brightenings
Morgan, Huw; Humphries, Llŷr Dafydd; Kuridze, David
Small-scale brightenings are ubiquitous, dynamic, and energetic phenomena found in the chromosphere. An advanced filter-detection algorithm applied to high-resolution observations from the Interface Region Imaging Spectrograph enables the detection of these brightenings close to the noise level. This algorithm also tracks the movement of these bri…