Search Publications

Spectral Properties and the Influence of Coronal Mass Ejections in 3He-rich Solar Energetic Particle Events
DOI: 10.3847/1538-4357/ad6b99 Bibcode: 2024ApJ...974..220H

Ho, G. C.; Mason, G. M.; Desai, M. I. +5 more

We analyze the spectral properties of 3He and 4He as well as the heavy ions (oxygen, neon, magnesium, silicon, and iron) in 80 3He-rich solar energetic particle (SEP) events observed by the Ultra-Low-Energy Ion Spectrometer on board the Advanced Composition Explorer spacecraft since its launch in 1997 until 2024. W…

2024 The Astrophysical Journal
SOHO SolarOrbiter 2
Doppler signature of a possible termination shock in an off-limb solar flare
DOI: 10.1093/mnras/stae430 Bibcode: 2024MNRAS.528.6836F

Chen, Bin; Yu, Sijie; Matthews, Sarah A. +2 more

We report striking Doppler velocity gradients observed during the well-observed 2017 September 10 solar flare, and argue that they are consistent with the presence of an above-the-looptop termination shock beneath the flare current sheet. Observations from the Hinode Extreme-ultraviolet Imaging Spectrometer measure plasma sheet Doppler shifts up t…

2024 Monthly Notices of the Royal Astronomical Society
Hinode 2
Probing the Dust Grain Alignment Mechanisms in Spiral Galaxies with M51 as the Case Study
DOI: 10.3847/1538-4357/ad7819 Bibcode: 2024ApJ...975..119L

Tram, Le Ngoc; Lopez-Rodriguez, Enrique

Magnetic fields (B fields) in galaxies have recently been traced using far-infrared and submillimeter polarimetric observations with the Stratospheric Observatory for Infrared Astronomy, James Clerk Maxwell Telescope, and Atacama Large Millimeter/submillimeter Array. The main assumption is that dust grains are magnetically aligned with the local B…

2024 The Astrophysical Journal
Herschel 2
A search for intermediate-mass black holes in compact stellar systems through optical emissions from tidal disruption events
DOI: 10.1093/mnras/stae960 Bibcode: 2024MNRAS.530.3043P

Norris, Mark A.; Pomeroy, Richard T.

Intermediate-mass black holes (IMBHs) are expected to exist in globular clusters (GCs) and compact stellar systems (CSSs) in general, but none have been conclusively detected. Tidal disruption events (TDEs), where a star is tidally disrupted by the gravitational field of a black hole, have been observed to occur around the supermassive black holes…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 2
BepiColombo observations of cold oxygen and carbon ions in the flank of the induced magnetosphere of Venus
DOI: 10.1038/s41550-024-02247-2 Bibcode: 2024NatAs...8..716H

André, N.; Fedorov, A.; Krupp, N. +25 more

On 10 August 2021, the Mercury-bound BepiColombo spacecraft performed its second fly-by of Venus and provided a short-lived observation of its induced magnetosphere. Here we report results recorded by the Mass Spectrum Analyzer on board Mio, which reveal the presence of cold O+ and C+ with an average total flux of ~4 ± 1 × 10…

2024 Nature Astronomy
BepiColombo 2
Properties of sunspot light bridges on a geometric height scale
DOI: 10.1051/0004-6361/202348181 Bibcode: 2024A&A...689A.255E

Ruiz Cobo, B.; Asensio Ramos, A.; Esteban Pozuelo, S. +1 more

Context. Investigating light bridges (LBs) helps us comprehend key aspects of sunspots. However, few studies have analyzed the properties of LBs in terms of the geometric height, which is a more realistic perspective given the corrugation of the solar atmosphere. Aims. We aim to shed light on LBs by studying the variation in their physical propert…

2024 Astronomy and Astrophysics
Hinode 2
Three young planets around the K-dwarf K2-198: high-energy environment, evaporation history, and expected future
DOI: 10.1093/mnras/stad3197 Bibcode: 2024MNRAS.527..374K

Baratella, M.; Poppenhaeger, K.; Ilin, E. +1 more

Planets orbiting young stars are thought to experience atmospheric evaporation as a result of the host stars' high-magnetic activity. We study the evaporation history and expected future of the three known transiting exoplanets in the young multiplanet system K2-198. Based on spectroscopic and photometric measurements, we estimate an age of the K-…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 2
Maser Investigation toward Off-Plane Stars (MIOPS): Detection of SiO Masers in the Galactic Thick Disk and Halo
DOI: 10.3847/1538-4357/ad05cb Bibcode: 2024ApJ...961..190Y

Li, Juan; Gong, Yan; Menten, Karl M. +7 more

Studying stars that are located off the Galactic plane is important for understanding the formation history of the Milky Way. We searched for SiO masers toward off-plane O-rich asymptotic giant branch (AGB) stars from the catalog presented by Mauron et al. in order to shed light on the origins of these objects. A total of 102 stars were observed i…

2024 The Astrophysical Journal
Gaia 2
Neglected Silicon Dioxide Polymorphs as Clouds in Substellar Atmospheres
DOI: 10.3847/2041-8213/ad72e7 Bibcode: 2024ApJ...973L...3M

Moran, Sarah E.; Marley, Mark S.; Crossley, Samuel D.

Direct mid-infrared signatures of silicate clouds in substellar atmospheres were first detected in Spitzer observations of brown dwarfs, although their existence was previously inferred from near-infrared spectra. With JWST's Mid-Infrared Instrument, we can now more deeply probe silicate features from 8 to 10 µm, exploring specific particle …

2024 The Astrophysical Journal
JWST 2
Studying the variability of fluorescence emission and the presence of clumpy wind in HMXB GX 301-2 using XMM-Newton
DOI: 10.1093/mnras/stad3395 Bibcode: 2024MNRAS.527.2652R

Paul, Biswajit; Roy, Kinjal; Manikantan, Hemanth

We present the results from an analysis of data from an XMM-Newton observation of the accreting high-mass X-ray binary pulsar GX 301-2. Spectral analysis in the non-flaring segment of the observation revealed that the equivalent width of the iron fluorescence emission is correlated with the observed absorption column density and the ratio of the i…

2024 Monthly Notices of the Royal Astronomical Society
XMM-Newton 2