Search Publications
Ulysses Observations of Magnetic Waves Due to Newborn Interstellar Pickup Ions. II. Application of Turbulence Concepts to Limiting Wave Energy and Observability
Isenberg, Philip A.; Murphy, Neil; Cannon, Bradford E. +4 more
The low-frequency magnetic waves that arise from the isotropization of newborn interstellar pickup ions (PUIs) are reasonably well described by linear and quasi-linear kinetic theory in so far as those theories predict the wave frequency and polarization in the spacecraft frame. Those theories fail to describe the scarce observability of the waves…
Preliminary Analysis of SOHO/STEREO Observations of Sungrazing Comet ISON (C/2012 S1) around Perihelion
Knight, Matthew M.; Battams, Karl
We present photometric and morphological analysis of the behavior of sungrazing comet C/2012 S1 ISON in Solar and Heliospheric Observatory (SOHO) and Solar TErrestrial RElations Observatory (STEREO) images around its perihelion on 2013 November 28.779 UT. ISON brightened gradually November 20-26 with a superimposed outburst on November 21.3-23.5. …
Universal profiles of the intracluster medium from Suzaku X-ray and Subaru weak-lensing observations*
Sato, Kosuke; Fukazawa, Yasushi; Nakazawa, Kazuhiro +16 more
We conduct a joint X-ray and weak-lensing study of four relaxed galaxy clusters (Hydra A, A 478, A 1689, and A 1835) observed by both Suzaku and Subaru out to virial radii, with the aim of understanding recently discovered unexpected features of the intracluster medium (ICM) in cluster outskirts. We show that the average hydrostatic-to-lensing tot…
Electron Dynamics in the Diffusion Region of an Asymmetric Magnetic Reconnection
Fazakerley, A. N.; André, M.; Vaivads, A. +2 more
During a magnetopause crossing near the subsolar point Cluster observes the ion diffusion region of antiparallel magnetic reconnection. The reconnecting plasmas are asymmetric, differing in magnetic field strength, density, and temperature. Spatial changes in the electron distributions in the diffusion region are resolved and investigated in detai…
Magnetic field topology for northward IMF reconnection: Ion observations
Lavraud, B.; Fuselier, S. A.; Trattner, K. J. +1 more
Ion observations from the Cluster spacecraft are used to investigate magnetopause reconnection for northward Interplanetary Magnetic Field (IMF) conditions. When the spacecraft cross the magnetopause and enter the magnetosphere at low latitudes, equatorward of the magnetospheric cusps, multiple ion populations of magnetosheath origin are almost al…
Untangling the Nature of Spatial Variations of Cold Dust Properties in Star Forming Galaxies
Kirkpatrick, Allison; Calzetti, Daniela; Dale, Daniel +7 more
We investigate the far-infrared (IR) dust emission for 20 local star forming galaxies from the Key Insights on Nearby Galaxies: A Far-IR Survey with Herschel (KINGFISH) sample. We model the far-IR/submillimeter spectral energy distribution (SED) using images from Spitzer Space Telescope and Herschel Space Observatory. We calculate the cold dust te…
A Spectroscopic Survey of WISE-selected Obscured Quasars with the Southern African Large Telescope
Myers, Adam D.; Hainline, Kevin N.; Hickox, Ryan C. +3 more
We present the results of an optical spectroscopic survey of a sample of 40 candidate obscured quasars identified on the basis of their mid-infrared emission detected by the Wide-Field Infrared Survey Explorer (WISE). Optical spectra for this survey were obtained using the Robert Stobie Spectrograph on the Southern African Large Telescope. Our sam…
Evidence of Very Low Metallicity and High Ionization State in a Strongly Lensed, Star-forming Dwarf Galaxy at z= 3.417
Castellano, M.; Pentericci, L.; Merlin, E. +6 more
We investigate the gas-phase metallicity and Lyman continuum (LyC) escape fraction of a strongly gravitationally lensed, extreme emission-line galaxy at z = 3.417, J1000+0221S, recently discovered by the CANDELS team. We derive ionization- and metallicity-sensitive emission-line ratios from H+K band Large Binocular Telescope (LBT)/LUCI medium reso…
A variable P v broad absorption line and quasar outflow energetics
Hamann, F.; Capellupo, D. M.; Barlow, T. A.
Broad absorption lines (BALs) in quasar spectra identify high-velocity outflows that might exist in all quasars and could play a major role in feedback to galaxy evolution. The viability of BAL outflows as a feedback mechanism depends on their kinetic energies, as derived from the outflow velocities, column densities, and distances from the centra…
Comparison of Extreme Ultraviolet Imaging Spectrometer Observations of Solar Coronal Loops with Alfvén Wave Turbulence Models
van Ballegooijen, A. A.; Imada, S.; Asgari-Targhi, M.
The observed non-thermal widths of coronal emission lines could be due to Alfvén wave turbulence. To test this idea, we examine and analyze the dynamics of an active region observed on 2012 September 7. We use spectral line profiles of Fe XII, Fe XIII, Fe XV, and Fe XVI obtained by the Extreme-ultraviolet Imaging Spectrometer on the it Hinode spac…