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First determination of the angular dependence of rise and decay times of solar radio bursts using multi-spacecraft observations
Maksimovic, Milan; Kontar, Eduard P.; Chen, Xingyao +3 more
A large arsenal of space-based and ground-based instruments is dedicated to the observation of radio emissions, whether they originate within our solar system or not. Radio photons interact with anisotropic density fluctuations in the heliosphere which can alter their trajectory and influence the properties that are deduced from observations. This…
The X-ray enhancements of radio-loud quasars at high redshift: new results at z = 4-7
Brandt, W. N.; Garmire, Gordon P.; Xue, Yongquan +4 more
Highly radio-loud quasars (HRLQs; log R > 2.5) at z ≳ 4 show apparent enhanced X-ray emission compared to matched HRLQs at lower redshifts, perhaps due to a redshift-dependent fractional contribution to the X-ray luminosity from inverse-Compton scattering of cosmic microwave background photons (IC/CMB). Using new Chandra observations and archiv…
Vortex Fiber Nulling for Exoplanet Observations: First Direct Detection of M Dwarf Companions around HIP 21543, HIP 94666, and HIP 50319
Monnier, John D.; Schaefer, Gail H.; Lanthermann, Cyprien +35 more
Vortex fiber nulling (VFN) is a technique for detecting and characterizing faint companions at small separations from their host star. A near-infrared (∼2.3 µm) VFN demonstrator mode was deployed on the Keck Planet Imager and Characterizer (KPIC) instrument at the Keck Observatory and presented earlier. In this Letter, we present the first V…
A Radio Counterpart to a Jupiter-mass Binary Object in Orion
Zapata, Luis A.; Rodríguez, Luis F.; Loinard, Laurent
Using James Webb Space Telescope near-infrared data of the inner Orion Nebula, Pearson & McCaughrean detected 40 Jupiter-mass binary objects (JuMBOs). These systems are not associated with stars and their components have masses of giant Jupiter-like planets and separations in the plane of the sky of order ~100 au. The existence of these wide f…
Magnetic Activity of Millions of G-type Stars Based on the LAMOST DR10 Low-resolution Spectral and TESS Light-curve Surveys and the Future CSST Survey
Han, Xianming L.; Misra, Prabhakar; Zhang, Li-yun +5 more
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) data release 10 (DR10) provides over 3 million G-type stellar spectra, which are important for the study of chromospheric activity of solar-like stars. We have used the iSpec program to perform spectral subtraction on the G-type stellar spectra obtained from LAMOST DR10 with a …
Role of Polycyclic Aromatic Hydrocarbons with Edge Defects in Explaining Astronomical Infrared Emission Observations
Boersma, C.; Peeters, E.; Maragkoudakis, A. +2 more
A systematic study was performed on the spectral properties of polycyclic aromatic hydrocarbons (PAHs) with edge defects using harmonic density functional theory calculations. Their potential astronomical relevance was assessed through direct comparison with NIRSpec and MIRI-MRS spectra of the atomic photodissociation region of the Orion Bar from …
The Composition of Saturn's Rings
Nicholson, Philip D.; Johnson, Robert E.; Hedman, Matthew M. +13 more
The origin and evolution of Saturn's rings is critical to understanding the Saturnian system as a whole. Here, we discuss the physical and chemical composition of the rings, as a foundation for evolutionary models described in subsequent chapters. We review the physical characteristics of the main rings, and summarize current constraints on their …
zoomies: A Tool to Infer Stellar Age from Vertical Action in Gaia Data
Hogg, David W.; Angus, Ruth; Price-Whelan, Adrian M. +3 more
Stellar age measurements are fundamental to understanding a wide range of astronomical processes, including Galactic dynamics, stellar evolution, and planetary system formation. However, extracting age information from main-sequence stars is complicated, with techniques often relying on age proxies in the absence of direct measurements. The Gaia d…
A Large Jet Narrow-line Seyfert 1 Galaxy: Observations from Parsec to 100 kpc Scales
Laor, Ari; Behar, Ehud; La Mura, Giovanni +11 more
We present new 1.5–8.5 GHz Very Long Baseline Array (VLBA) observations and 0.32–1.26 GHz Giant Meterwave Radio Telescope (GMRT) observations of J0354‑1340, which is the only known radio-quiet (RQ) or radio-intermediate (RI) narrow-line Seyfert 1 galaxy with a 100 kpc, two-sided radio jet. A parsec-scale, one-sided jet in the southeastern directio…
The Distance to the S147 Supernova Remnant
Kochanek, C. S.; Caldwell, Nelson; Raymond, John C.
In the absence of a parallax distance to a pulsar or a surviving binary in a supernova remnant (SNR), distances to Galactic SNRs are generally very uncertain. However, by combining Gaia data with wide-field, multifiber echelle spectroscopy, it is now possible to obtain accurate distances to many SNRs with limited extinction by searching for the ap…