Search Publications
JWST Detects Neon Line Variability in a Protoplanetary Disk
Muzerolle Page, J.; Walter, F. M.; McClure, M. K. +6 more
We report the first detection of variability in the mid-infrared neon line emission of a protoplanetary disk by comparing a JWST Mid-InfraRed Instrument Medium Resolution Spectrometer spectrum of SZ Cha taken in 2023 with a Spitzer Infrared Spectrograph Short-High spectrum of this object from 2008. We measure the [Ne III]-to-[Ne II] line flux rati…
Global Morphology Distortion of the 2021 October 9 Coronal Mass Ejection from an Ellipsoid to a Concave Shape
He, Jiansen; Shen, Fang; Feng, Xueshang +9 more
This paper presents a study of a 2021 October 9 coronal mass ejection (CME) with multipoint imaging and in situ observations. We also simulate this CME from the Sun to Earth with a passive tracer to tag the CME's motion. The coronagraphic images show that the CME is observed as a full halo by SOHO and as a partial halo by STEREO-A. The heliospheri…
Extended 3He-rich Time Periods Observed by Solar Orbiter: Magnetic Connectivity and Sources
Allen, R. C.; Ho, G. C.; Mason, G. M. +4 more
Observations of Solar Energetic Particles (SEPs) using the Suprathermal Ion Spectrograph (SIS), which is part of the Energetic Particle Detector suite on the Solar Orbiter mission, present an unprecedented opportunity to investigate the composition and evolution of SEPs in close proximity to the Sun. By analyzing data from the SIS instrument, we h…
Morphology of Solar Type II Bursts Caused by Shock Propagation through Turbulent and Inhomogeneous Coronal Plasma
Koval, Artem; Stanislavsky, Aleksander; Konovalenko, Aleksander +4 more
Type II solar bursts are radio signatures of shock waves in the solar corona driven by solar flares or coronal mass ejections (CMEs). Therefore, these bursts present complex spectral morphologies in solar dynamic spectra. Here, we report meter-decameter radio observations of a type II burst on 2014 July 25 made with the Ukrainian radio telescopes …
Solar Coronal Density Turbulence and Magnetic Field Strength at the Source Regions of Two Successive Metric Type II Radio Bursts
Kumari, Anshu; Ramesh, R.; Kathiravan, C.
We report spectral and polarimeter observations of two weak, low-frequency (≈85-60 MHz) solar coronal type II radio bursts that occurred on 2020 May 29 within a time interval ≈2 minutes. The bursts had fine structures, and were due to harmonic plasma emission. Our analysis indicates that the magnetohydrodynamic shocks responsible for the first and…
CO Survey of High-z Radio Galaxies, Revisited with the Atacama Large Millimeter/submillimeter Array: Jet-Cloud Alignments and Synchrotron Brightening by Molecular Gas in the Circumgalactic Environment
Carilli, Chris; Lehnert, Matthew D.; De Breuck, Carlos +6 more
Powerful radio sources associated with supermassive black holes are among the most luminous objects in the universe, and are frequently recognized both as cosmological probes and active constituents in the evolution of galaxies. We present alignments between radio jets and cold molecular gas in the environment of distant radio galaxies, and show t…
Constraining the Systematics of (Acoustic) Wave Heating Estimates in the Solar Chromosphere
Kowalski, Adam F.; Cranmer, Steven R.; Reardon, Kevin P. +2 more
Acoustic wave heating is believed to contribute significantly to the missing energy input required to maintain the solar chromosphere in its observed state. We studied the propagation of waves above the acoustic cutoff in the upper photosphere into the chromosphere with ultraviolet and optical spectral observations interpreted through comparison w…
The Disturbed and Globular-cluster-rich Ultradiffuse Galaxy UGC 9050-Dw1
Sand, David J.; Jones, Michael G.; Fielder, Catherine E. +5 more
We investigate the ultradiffuse galaxy (UDG) UGC 9050-Dw1, which was selected because of its disturbed morphology as part of a larger sample of UDGs that display evidence for significant interactions. We use the Hubble Space Telescope's Advanced Camera for Surveys to identify globular clusters (GCs) associated with UGC 9050-Dw1, and the Jansky Ver…
Obscuring Environment and X-Ray Variability of Compact Symmetric Objects Unveiled with XMM-Newton and NuSTAR
Ostorero, Luisa; Guainazzi, Matteo; Stawarz, Łukasz +3 more
Compact symmetric objects (CSOs) show radio features such as jets, lobes, and hot spots, which are contained within their host galaxies, and likely represent a recent radio activity. A subpopulation of CSOs with high intrinsic X-ray column densities has been inferred from shallow, soft X-ray band exposures, and observed to cluster in the linear ra…
M92 (NGC 6341) Is a Metal-complex Globular Cluster with an Atypical Primordial Population
Lee, Jae-Woo
We present a multiple stellar population study of the metal-poor globular cluster (GC) M92 (NGC 6341), which is long known for the substantial metallicity dispersion, using our own photometric system. We find two groups with slightly different mean metallicities, the metal-poor (MP) stars with [Fe/H] hk = -2.412 ± 0.03 and the metal-ri…