Search Publications

Imaging and spectroscopic observations of a confined solar filament eruption with two-stage evolution
DOI: 10.1093/mnras/stae822 Bibcode: 2024MNRAS.530..473X

Xu, Zhe; Xue, Zhike; Yan, Xiaoli +3 more

Solar filament eruptions are often characterized by stepwise evolution due to the involvement of multiple mechanisms, such as magnetohydrodynamic instabilities and magnetic reconnection. In this article, we investigated a confined filament eruption with a distinct two-stage evolution by using the imaging and spectroscopic observations from the Int…

2024 Monthly Notices of the Royal Astronomical Society
IRIS 1
Identification of A-type supergiants from LAMOST DR5
DOI: 10.1093/mnras/stae558 Bibcode: 2024MNRAS.531.1244H

Liu, Chao; Liu, Zhicun; Cui, Wenyuan +7 more

We present a new method for selecting A-type supergiants (A-SGs hereafter) in the LAMOST DR5 data set using the line indices, and identify 40 spectra of 30 A-SG candidates. Based on the analysis of the absolute magnitude of Gaia DR3, SIMBAD data base, ZTF light variation data, and spectral characteristics of A-SGs, we classified the 30 A-SG candid…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 1
SRG/eROSITA 3D mapping of the interstellar medium using X-ray absorption spectroscopy
DOI: 10.1051/0004-6361/202449374 Bibcode: 2024A&A...688A.207G

Czesla, S.; Kallman, T. R.; Wilms, J. +6 more

We present a detailed study of the hydrogen density distribution in the local interstellar medium (ISM) using the X-ray absorption technique. Hydrogen column densities were precisely measured by fitting X-ray spectra from coronal sources observed during the initial eROSITA all-sky survey (eRASS1). Accurate distance measurements were obtained throu…

2024 Astronomy and Astrophysics
Gaia 1
Using Polar Faculae to Determine the Sun's High-latitude Rotation Rate. I. Techniques and Initial Measurements
DOI: 10.3847/1538-4357/ad85d0 Bibcode: 2024ApJ...976...73S

Sheeley, Neil R.

This paper describes a new way of determining the high-latitude solar rotation rate statistically from simultaneous observations of many polar faculae. In this experiment, I extracted frames from a movie made previously from flat-fielded images obtained in the 6767 Å continuum during 1997–1998 February and used those frames to construct spacetime …

2024 The Astrophysical Journal
SOHO 1
Dynamical Mass of the Ophiuchus Intermediate-mass Stellar System S1 with DYNAMO-VLBA
DOI: 10.3847/1538-3881/ad1bd3 Bibcode: 2024AJ....167..108O

Dupuy, Trent J.; Rodríguez, Luis F.; Loinard, Laurent +8 more

We report dynamical mass measurements of the individual stars in the most luminous and massive stellar member of the nearby Ophiuchus star-forming region, the young tight binary system S1. We combine 28 archival data sets with seven recent proprietary Very Long Baseline Array (VLBA) observations obtained as part of the Dynamical Masses of Young St…

2024 The Astronomical Journal
Gaia 1
Large Eruptive and Confined Flares in Relation to the Solar Active Region Evolution
DOI: 10.3847/2041-8213/ad8c37 Bibcode: 2024ApJ...976L...2L

Liu, Yu; Wang, Huaning; Rao, Changhui +5 more

Solar active regions (ARs) provide the required magnetic energy and the topology configuration for flares. Apart from conventional static magnetic parameters, the evolution of AR magnetic flux systems should have nonnegligible effects on magnetic energy store and the trigger mechanism of eruptions, which would promote the prediction for the flare …

2024 The Astrophysical Journal
SOHO 1
Coupling between magnetic reconnection, energy release, and particle acceleration in the X17.2 2003 October 28 solar flare
DOI: 10.1051/0004-6361/202349130 Bibcode: 2024A&A...686A.195K

Veronig, Astrid M.; Hinterreiter, Jürgen; Fleishman, Gregory D. +3 more

Context. The 2003 October 28 (X17.2) eruptive flare was a unique event. The coronal electric field and the π-decay γ-ray emission flux displayed the highest values ever inferred for solar flares.
Aims: Our aim is to reveal physical links between the magnetic reconnection process, energy release, and acceleration of electrons and ions to high …

2024 Astronomy and Astrophysics
INTEGRAL SOHO 1
Spectral analysis of three hot subdwarf stars: EC 11481-2303, Feige 110, and PG 0909+276. A critical oscillator-strength evaluation for iron-group elements
DOI: 10.1051/0004-6361/202450695 Bibcode: 2024A&A...688A.101L

Rauch, T.; Werner, K.; Landstorfer, A.

Context. For the precise spectral analysis of hot stars, advanced stellar-atmosphere models that consider deviations from the local thermodynamic equilibrium are mandatory. This requires accurate atomic data to calculate all transition rates and occupation numbers for atomic levels in the considered model atoms, not only for a few prominent lines …

2024 Astronomy and Astrophysics
Gaia eHST 1
The double low-mass white dwarf eclipsing binary system J2102-4145 and its possible evolution
DOI: 10.1051/0004-6361/202348564 Bibcode: 2024A&A...685A...9A

Dhillon, V. S.; Marsh, T. R.; Littlefair, S. P. +7 more

In recent years, about 150 low-mass white dwarfs (WDs), typically with masses below 0.4 M, have been discovered. The majority of these low-mass WDs are observed in binary systems as they cannot be formed through single-star evolution within Hubble time. In this work, we present a comprehensive analysis of the double low-mass WD eclipsi…

2024 Astronomy and Astrophysics
Gaia 1
The Plasma β in Quiet Sun Regions: Multi-instrument View
DOI: 10.3847/1538-4357/ad1f64 Bibcode: 2024ApJ...964...27R

Veronig, Astrid; Podladchikova, Tatiana; Gömöry, Peter +4 more

A joint campaign of several spaceborne and ground-based observatories, such as the GREGOR solar telescope, the Extreme-ultraviolet Imaging Spectrometer (EIS), and the Interface Region Imaging Spectrograph (Hinode Observing Plan 381, 2019 October 11–22) was conducted to investigate the plasma β in quiet Sun regions. In this work, we focus on 2019 O…

2024 The Astrophysical Journal
Hinode IRIS 1