Search Publications
HST UV Observations of Asteroid (16) Psyche
Roth, Lorenz; Feaga, Lori M.; Becker, Tracy M. +7 more
The Main Belt Asteroid (16) Psyche is the target object of the NASA Discovery Mission Psyche. We observed the asteroid at ultraviolet (UV) wavelengths (170-310 nm) using the Space Telescope Imaging Spectrograph on the Hubble Space Telescope during two separate observations. We report that the spectrum is very red in the UV, with a blue upturn shor…
Extraplanar Gas in Edge-on Galaxies Traced by SOFIA Observations of [C II]
Reach, William T.; Fadda, Dario; Stacey, Gordon J. +1 more
Bursts of localized star formation in galaxies can levitate material from the midplane. Spiral galaxies that are edge-on allow a clear distinction of material that is levitated off the galaxies' midplanes. We used SOFIA to measure the vertical distribution of [C II] 157.7 µm line emission for two nearby, edge-on galaxies, NGC 891 and NGC 590…
Cause and Kinematics of a Jetlike CME
Wang, Yuming; Joshi, Reetika; Chandra, Ramesh +3 more
In this article, we present the multiviewpoint and multiwavelength analysis of an atypical solar jet based on data from Solar Dynamics Observatory, SOlar and Heliospheric Observatory, and Solar TErrestrial RElations Observatory. It is generally believed that coronal mass ejections (CMEs) develop from the large-scale solar eruptions in the lower at…
The cooling-down central star of the planetary nebula SwSt 1: a late thermal pulse in a massive post-AGB star?
Hamann, Wolf-Rainer; Todt, Helge; Zijlstra, Albert A. +3 more
SwSt 1 (PN G001.5-06.7) is a bright and compact planetary nebula containing a late [WC]-type central star. Previous studies suggested that the nebular and stellar lines are slowly changing with time. We studied new and archival optical and ultraviolet spectra of the object. The [O III] 4959 and 5007 Å to H β line flux ratios decreased between abou…
Equilibrium axisymmetric halo model for the Milky Way and its implications for direct and indirect dark matter searches
Petač, Mihael
We for the first time provide self-consistent axisymmetric phase-space distribution models for the Milky Way's dark matter (DM) halo which are carefully matched against the latest kinematic measurements through Bayesian analysis. By using broad priors on the individual galactic components, we derive conservative estimates for the astrophysical fac…
The efficiency of nuclear burning during thermonuclear (Type I) bursts as a function of accretion rate
Cavecchi, Y.; Galloway, D. K.; Heger, A. +2 more
We measured the thermonuclear burning efficiency as a function of accretion rate for the Type I X-ray bursts of five low-mass X-ray binary systems. We chose sources with measured neutron star spins and a substantial population of bursts from a large observational sample. The general trend for the burst rate is qualitatively the same for all source…
Characterization of the umbra-penumbra boundary by the vertical component of the magnetic field. Analysis of ground-based data from the GREGOR Infrared Spectrograph
Bello González, N.; Schlichenmaier, R.; Lindner, P.
Context. The vertical component of the magnetic field was found to reach a constant value at the boundary between penumbra and umbra of stable sunspots in a recent statistical study of Hinode/SP data. This finding has profound implications as it can serve as a criterion to distinguish between fundamentally different magneto-convective modes operat…
Shear Measurement Bias Due to Spatially Varying Spectral Energy Distributions in Galaxies
Burchat, Patricia R.; Meyers, Joshua E.; Kamath, Sowmya +1 more
Galaxy color gradients (CGs)—I.e., spectral energy distributions that vary across the galaxy profile—will impact galaxy shape measurements when the modeled point-spread function (PSF) corresponds to that for a galaxy with spatially uniform color. This paper describes the techniques and results of a study of the expected impact of galaxy CGs on wea…
Mechanochemical synthesis of aromatic infrared band carriers. The top-down chemistry of interstellar carbonaceous dust grain analogues
Engrand, C.; Dartois, E.; Charon, E. +2 more
Context. Interstellar space hosts nanometre- to micron-sized dust grains, which are responsible for the reddening of stars in the visible. The carbonaceous-rich component of these grain populations emits in infrared bands that have been observed remotely for decades with telescopes and satellites. They are a key ingredient of Galactic radiative tr…
High-resolution spectroscopy of the high-velocity hot post-AGB star IRAS 18379-1707 (LS 5112)
Hubrig, S.; Parthasarathy, M.; Ikonnikova, N. P. +2 more
The high-resolution (R∼ 48 000) optical spectrum of the B-type supergiant LS 5112, identified as the optical counterpart of the post-AGB candidate IRAS 18379-1707 is analysed. We report the detailed identifications of the observed absorption and emission features in the wavelength range 3700-9200 Å for the first time. The absorption line spectrum …