Search Publications
A Coronal Mass Ejection and Magnetic Ejecta Observed In Situ by STEREO-A and Wind at 55° Angular Separation
Lugaz, Noé; Zhuang, Bin; Scolini, Camilla +8 more
We present an analysis of in situ and remote-sensing measurements of a coronal mass ejection (CME) that erupted on 2021 February 20 and impacted both the Solar TErrestrial RElations Observatory (STEREO)-A and the Wind spacecraft, which were separated longitudinally by 55°. Measurements on 2021 February 24 at both spacecraft are consistent with the…
A first estimate of the Milky Way dark matter halo spin
Buck, Tobias; Macciò, Andrea V.; Obreja, Aura
The spin, or normalized angular momentum λ, of dark matter halos in cosmological simulations follows a log normal distribution and has little correlation with galaxy observables such as stellar masses or sizes. There is currently no way to infer the λ parameter of individual halos hosting observed galaxies. Here, we present a first attempt to meas…
Toward Improved Understanding of Magnetic Fields Participating in Solar Flares: Statistical Analysis of Magnetic Fields within Flare Ribbons
Savcheva, Antonia; Kazachenko, Maria D.; Lynch, Benjamin J. +2 more
Violent solar flares and coronal mass ejections (CMEs) are magnetic phenomena. However, how magnetic fields reconnecting in the flare differ from nonflaring magnetic fields remains unclear owing to the lack of studies of the flare magnetic properties. Here we present a first statistical study of flaring (highlighted by flare ribbons) vector magnet…
Mapping Milky Way disk perturbations in stellar number density and vertical velocity using Gaia DR3
Widmark, A.; Widrow, L. M.; Naik, A.
We have mapped the number density and mean vertical velocity of the Milky Way's stellar disk out to roughly two kiloparsecs from the Sun using Gaia Data Release 3 (DR3) and complementary photo-astrometric distance information from StarHorse. For the number counts, we carefully masked spatial regions that are compromised by open clusters, great dis…
The origin of close massive binaries in the M17 star-forming region
Sana, H.; Frost, A. J.; Reggiani, M. +5 more
Context. Spectroscopic multiplicity surveys of O stars in young clusters and OB associations have revealed that a large portion (∼70%) of these massive stars (Mi > 15 M⊙) belong to close and short-period binaries (with a physical separation of less than a few astronomical units). Follow-up VLT(I) high-angular-resolution ob…
FEEDBACK from the NGC 7538 H II region
Schneider, N.; Beuther, H.; Tielens, A. G. G. M. +10 more
Context. The interaction of expanding H II regions with their environmental clouds is one of the central questions driving the Stratospheric Observatory for Infrared Astronomy (SOFIA) legacy program FEEDBACK.
Aims: We want to understand the interaction of the prototypical NGC 7538 H II region with the neighboring molecular cloud hosting sever…
Solar Flare Heating with Turbulent Suppression of Thermal Conduction
Gordon Emslie, A.; Kerr, Graham S.; Allred, Joel C.
During solar flares, plasma is typically heated to very high temperatures, and the resulting redistribution of energy via thermal conduction is a primary mechanism transporting energy throughout the flaring solar atmosphere. The thermal flux is usually modeled using Spitzer's theory, which is based on local Coulomb collisions between the electrons…
Atomic and molecular gas from the epoch of reionisation down to redshift 2
Ciardi, Benedetta; Péroux, Céline; Maio, Umberto
Context. Cosmic gas makes up about 90% of the baryonic matter in the Universe and H2 molecule is the most tightly linked to star formation.
Aims: In this work we study cold neutral gas, its H2 component at different epochs, and corresponding depletion times.
Methods: We perform state-of-the-art hydrodynamic simulati…
J-PLUS: Searching for very metal-poor star candidates using the SPEEM pipeline
Sobral, David; Lee, Young Sun; Placco, Vinicius M. +25 more
Context. We explore the stellar content of the Javalambre Photometric Local Universe Survey (J-PLUS) Data Release 2 and show its potential for identifying low-metallicity stars using the Stellar Parameters Estimation based on Ensemble Methods (SPEEM) pipeline.
Aims: SPEEM is a tool used to provide determinations of atmospheric parameters for …
Where outflows meet inflows: gas kinematics in SSA22 Ly α blob 2 decoded by advanced radiative transfer modelling
Steidel, Charles C.; Gronke, Max; Li, Zhihui +2 more
We present new spectroscopic observations of Ly α (Ly α) Blob 2 (z ~ 3.1). We observed extended Ly α emission in three distinct regions, where the highest Ly α surface brightness (SB) centre is far away from the known continuum sources. We searched through the MOSFIRE slits that cover the high Ly α SB regions, but were unable to detect any signifi…