Search Publications
Challenges in Forecasting the Evolution of a Distorted CME Observed During the First Close Solar Orbiter Perihelion
Telloni, Daniele; Liberatore, Alessandro; Vourlidas, Angelos +11 more
Coronal Mass Ejections (CMEs), drivers of the most severe Space Weather disturbances, are often assumed to evolve self-similarly during their propagation. However, open magnetic field structures in the corona, leading to higher-speed streams in the ambient solar wind, can be source of strong distortions of the CME front. In this paper, we investig…
Parkes Radio and NuSTAR X-Ray Observations of the Composite Supernova Remnant B0453–685 in the Large Magellanic Cloud
Acero, Fabio; Ballet, Jean; Kerr, Matthew +9 more
Gamma-ray emission is observed coincident in position to the evolved, composite supernova remnant (SNR) B0453–685. Prior multiwavelength investigations of the region indicate that the pulsar wind nebula (PWN) within the SNR is the most likely origin for the observed gamma rays, with a possible pulsar contribution that becomes significant at energi…
Kinematic Insights into Luminous Blue Variables and B[e] Supergiants
Oey, M. S.; Deman, Julian A.
Recent work suggests that many luminous blue variables (LBVs) and B[e] supergiants (sgB[e]) are isolated, implying that they may be products of massive binaries, kicked by partner supernovae. However, the evidence is somewhat complex and controversial. To test this scenario, we measure the proper-motion velocities for these objects in the LMC and …
The Kinematic and Chemical Properties of the Close-in Planet Host Star 8 UMi
Wang, Wei; Huang, Yang; Beers, Timothy C. +11 more
A recent study by Hon et al. reported that a close-in planet around the red clump star, 8 UMi, should have been engulfed during the expansion phase of its parent star's evolution. They explained the survival of this exoplanet through a binary-merger channel for 8 UMi. The key to testing this formation scenario is to derive the true age of this sta…
The Calibration of Polycyclic Aromatic Hydrocarbon Dust Emission as a Star Formation Rate Indicator in the AKARI NEP Survey
Goto, Tomotsugu; Kim, Seong Jin; Burgarella, Denis +9 more
Polycyclic aromatic hydrocarbon (PAH) dust emission has been proposed as an effective extinction-independent star formation rate (SFR) indicator in the mid-infrared, but this may depend on conditions in the interstellar medium. The coverage of the AKARI/Infrared Camera (IRC) allows us to study the effects of metallicity, starburst intensity, and a…
A Luminous X-Ray Active Galactic Nucleus in the Dwarf–Dwarf Galaxy Merger RGG 66
Reines, Amy E.; Kimbrell, Seth J.
We present the discovery of a luminous X-ray active galactic nucleus (AGN) in the dwarf galaxy merger RGG 66. The black hole is predicted to have a mass of M BH ∼ 105.4 M ⊙ and to be radiating close to its Eddington limit (L bol/L Edd ∼ 0.75). The AGN in RGG 66 is notable both for its presence…
A Wave-corrected Assessment of the Local Midplane
Hinkel, Austin; Yin, Ziyuan
As the number of known Galactic structures mounts thanks to the Gaia Space Telescope, it is now pertinent to study methods for disentangling structures occupying the same regions of the Milky Way. Indeed, understanding the precise form of each individual structure and the interactions between structures may aid in understanding their origins and c…
Test for Echo: X-Ray Reflection Variability in the Seyfert-2 Active Galactic Nucleus NGC 4388
Brandt, W. N.; Arzoumanian, Zaven; Gendreau, Keith +4 more
We report on a study of the narrow Fe Kα line and reflection spectrum in the well-known Seyfert-2 active galactic nucleus (AGN), NGC 4388. X-ray spectra summed from two extensive NICER monitoring campaigns, separated by years, show strong evidence of variation in the direct continuum and reflected emission, but only small variations in the obscuri…
Revealing the Impact of Critical Stellar Central Density on Galaxy Quenching through Cosmic Time
Xu, Bingxiao; Peng, Yingjie
In a previous work, we investigated the structural and environmental dependence on quenching in the nearby universe. In this work, we extend our investigations to higher redshifts by combining galaxies from the Sloan Digital Sky Survey and The FourStar Galaxy Evolution surveys. In low density, we find a characteristic Σ1 kpc above which…
How Does the Structure of Rarefaction Regions Develop?
Němeček, Zdeněk; Ďurovcová, Tereza; Šafránková, Jana
A rarefaction region (RR) occurs at the trailing edge of the fast solar wind stream. It comes from an area of small longitudinal extent on the solar surface and exhibits a fine and complex structure. In our study, we did a superposed epoch analysis of the proton and α parameters across the RR and observed their gradual evolution. We did not find a…