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The solar wind in time - II. 3D stellar wind structure and radio emission
DOI: 10.1093/mnras/sty3132 Bibcode: 2019MNRAS.483..873O

Petit, P.; Vidotto, A. A.; Jeffers, S. V. +6 more

In this work, we simulate the evolution of the solar wind along its main-sequence lifetime and compute its thermal radio emission. To study the evolution of the solar wind, we use a sample of solar mass stars at different ages. All these stars have observationally reconstructed magnetic maps, which are incorporated in our 3D magnetohydrodynamic si…

2019 Monthly Notices of the Royal Astronomical Society
Gaia 32
Mass discrepancy analysis for a select sample of Type II-Plateau supernovae
DOI: 10.1051/0004-6361/201834818 Bibcode: 2019A&A...629A.124M

Bersten, Melina C.; Martinez, Laureano

The detailed study of supernovae (SNe) and their progenitors allows a better understanding of the evolution of massive stars and how these end their lives. Despite its importance, the range of physical parameters for the most common type of explosion, the type II supernovae (SNe II), is still unknown. In particular, previous studies of type II-Pla…

2019 Astronomy and Astrophysics
eHST 32
Spitzer Microlensing Parallax for OGLE-2017-BLG-0896 Reveals a Counter-rotating Low-mass Brown Dwarf
DOI: 10.3847/1538-3881/aafe12 Bibcode: 2019AJ....157..106S

Helling, Christiane; Maoz, Dan; Tan, Thiam-Guan +69 more

The kinematics of isolated brown dwarfs in the Galaxy, beyond the solar neighborhood, is virtually unknown. Microlensing has the potential to probe this hidden population, as it can measure both the mass and five of the six phase-space coordinates (all except the radial velocity) even of a dark isolated lens. However, the measurements of both the …

2019 The Astronomical Journal
Gaia 32
Spectroscopy and Differential Emission Measure Diagnostics of a Coronal Dimming Associated with a Fast Halo CME
DOI: 10.3847/1538-4357/ab2712 Bibcode: 2019ApJ...879...85V

Veronig, Astrid M.; Temmer, Manuela; Dissauer, Karin +2 more

We study the coronal dimming caused by the fast halo CME (deprojected speed v = 1250 km s-1) associated with the C3.7 two-ribbon flare on 2012 September 27, using Hinode/EIS spectroscopy and Solar Dynamics Observatory (SDO)/AIA Differential Emission Measure (DEM) analysis. The event reveals bipolar core dimmings encompassed by hook-shap…

2019 The Astrophysical Journal
Hinode SOHO 32
Revealing the Complicated Story of the Cetus Stream with StarGO
DOI: 10.3847/1538-4357/ab2e09 Bibcode: 2019ApJ...881..164Y

Chang, Jiang; Smith, M. C.; Liu, Chao +5 more

We use a novel cluster identification tool, STARGO, to explore the metal-poor ([Fe/H] < -1.5) outer stellar halo (d > 15 kpc) of the Milky Way using data from Gaia, LAMOST, and SDSS. Our method is built using an unsupervised learning algorithm, a self-organizing map, which trains a 2D neural network to learn the topological structures of a d…

2019 The Astrophysical Journal
Gaia 32
Simultaneous X-Ray and Infrared Observations of Sagittarius A*'s Variability
DOI: 10.3847/1538-4357/aaf71f Bibcode: 2019ApJ...871..161B

Ponti, G.; Fazio, G. G.; Morris, M. R. +11 more

Emission from Sagitarius A* is highly variable at both X-ray and infrared (IR) wavelengths. Observations over the last ∼20 yr have revealed X-ray flares that rise above a quiescent thermal background about once per day, while faint X-ray flares from Sgr A* are undetectable below the constant thermal emission. In contrast, the IR emission of Sgr A*…

2019 The Astrophysical Journal
eHST 32
A Wide and Deep Exploration of Radio Galaxies with Subaru HSC (WERGS). II. Physical Properties Derived from the SED Fitting with Optical, Infrared, and Radio Data
DOI: 10.3847/1538-4365/ab238d Bibcode: 2019ApJS..243...15T

Lee, Chien-Hsiu; Schramm, Malte; Ueda, Yoshihiro +14 more

We present physical properties of radio galaxies (RGs) with f 1.4 GHz > 1 mJy discovered by Subaru Hyper Suprime-Cam (HSC) and Very Large Array Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) survey. For 1056 FIRST RGs at 0 < z ≤ 1.7 with HSC counterparts in about 100 deg2, we compiled multi-wavelength data …

2019 The Astrophysical Journal Supplement Series
Herschel 32
Analysis of Small-scale Magnetic Flux Ropes Covering the Whole Ulysses Mission
DOI: 10.3847/1538-4357/ab2ccf Bibcode: 2019ApJ...881...58C

Hu, Qiang; Chen, Yu; le Roux, Jakobus A.

Small-scale magnetic flux ropes in the solar wind have been studied for decades via both simulation and observation. Statistical analysis utilizing various in situ spacecraft measurements is the main observational approach, which helps investigate the generation and evolution of these small-scale structures. In this study, we extend the automated …

2019 The Astrophysical Journal
Ulysses 32
The redshift evolution of X-ray and Sunyaev-Zel'dovich scaling relations in the FABLE simulations
DOI: 10.1093/mnras/stz2301 Bibcode: 2019MNRAS.489.2439H

Sijacki, Debora; Puchwein, Ewald; Henden, Nicholas A.

We study the redshift evolution of the X-ray and Sunyaev-Zel'dovich (SZ) scaling relations for galaxy groups and clusters in the FABLE suite of cosmological hydrodynamical simulations. Using an expanded sample of 27 high-resolution zoom-in simulations, together with a uniformly sampled cosmological volume to sample low-mass systems, we find very g…

2019 Monthly Notices of the Royal Astronomical Society
eHST 32
CME Arrival Time Prediction Using Convolutional Neural Network
DOI: 10.3847/1538-4357/ab2b3e Bibcode: 2019ApJ...881...15W

Liu, Jiajia; Erdélyi, Robert; Wang, Yimin +1 more

Fast and accurate prediction of the arrival time of coronal mass ejections (CMEs) at Earth is vital to minimize hazards caused by CMEs. In this paper, we use a deep-learning framework, i.e., a convolutional neural network (CNN) regression model, to analyze transit times from the Sun to Earth of 223 geoeffective CME events observed in the past 30 y…

2019 The Astrophysical Journal
SOHO 32