Search Publications
Modeling the Thermodynamic Evolution of Coronal Mass Ejections Using Their Kinematics
Wang, Yuming; Mishra, Wageesh
Earlier studies on coronal mass ejections (CMEs), using remote sensing and in situ observations, have attempted to determine some internal properties of CMEs, which were limited to a certain position or a certain time. To understand the evolution of the internal thermodynamic state of CMEs during their heliospheric propagation, we improve the self…
Texas Spectroscopic Search for Lyα Emission at the End of Reionization I. Constraining the Lyα Equivalent-width Distribution at 6.0 < z < 7.0
Papovich, Casey; Finkelstein, Steven L.; Dickinson, Mark +6 more
The distribution of Lyα emission is a presently accessible method for studying the state of the intergalactic medium (IGM) into the reionization era. We carried out deep spectroscopic observations in order to search for Lyα emission from galaxies with photometric redshifts z = 5.5-8.3 selected from the Cosmic Assembly Near-infrared Deep Extragalac…
Chandra and XMM-Newton Observations of the Abell 3395/Abell 3391 Intercluster Filament
Jones, Christine; Randall, Scott W.; Bourdin, Hervé +2 more
We present Chandra and XMM-Newton X-ray observations of the Abell 3391/Abell 3395 intercluster filament. It has been suggested that the galaxy clusters Abell 3395, Abell 3391, and the galaxy group ESO-161 -IG 006 located between the two clusters, are in alignment along a large-scale intercluster filament. We find that the filament is aligned close…
Constraints on the Mass, Concentration, and Nonthermal Pressure Support of Six CLASH Clusters from a Joint Analysis of X-Ray, SZ, and Lensing Data
Koekemoer, Anton M.; Donahue, Megan; Koch, Patrick M. +17 more
We present a joint analysis of Chandra X-ray observations, Bolocam thermal Sunyaev-Zel’dovich (SZ) effect observations, Hubble Space Telescope (HST) strong-lensing data, and HST and Subaru Suprime-Cam weak-lensing data. The multiwavelength data set is used to constrain parametric models for the distribution of dark and baryonic matter in a sample …
The Hot, Accreted Halo of NGC 891
Bregman, Joel N.; Hodges-Kluck, Edmund J.; Li, Jiang-tao
Galaxies are surrounded by halos of hot gas whose mass and origin remain unknown. One of the most challenging properties to measure is the metallicity, which constrains both of these. We present a measurement of the metallicity around NGC 891, a nearby, edge-on, Milky Way analog. We find that the hot gas is dominated by low-metallicity gas near th…
Plasma Diagnostics of Coronal Dimming Events
Veronig, Astrid M.; Temmer, Manuela; Dissauer, Karin +1 more
Coronal mass ejections are often associated with coronal dimmings, i.e., transient dark regions that are most distinctly observed in Extreme Ultra-violet wavelengths. Using Atmospheric Imaging Assembly (AIA) data, we apply Differential Emission Measure diagnostics to study the plasma characteristics of six coronal dimming events. In the core dimmi…
X-Ray and Optical Studies of the Redback System PSR J2129-0429
Ray, Paul S.; Kerr, Matthew; Hessels, Jason W. T. +6 more
PSR J2129-0429 is a 7.62 ms eclipsing millisecond pulsar (MSP) with a non-degenerate binary companion star that is likely in an early stage of the recycling process. It has one of the largest companion masses of a so-called “redback” (0.4 M ⊙) and has an unusually high surface magnetic field (1.6 × 109 G) for an MSP. We prese…
3D Anisotropy of Solar Wind Turbulence, Tubes, or Ribbons?
Grappin, Roland; Alexandrova, Olga; Verdini, Andrea +1 more
We study the anisotropy with respect to the local magnetic field of turbulent magnetic fluctuations at magnetofluid scales in the solar wind. Previous measurements in the fast solar wind obtained axisymmetric anisotropy, despite that the analysis method allows nonaxisymmetric structures. These results are probably contaminated by the wind expansio…
ZFOURGE: Using Composite Spectral Energy Distributions to Characterize Galaxy Populations at 1 < z < 4
Papovich, Casey; Kacprzak, Glenn G.; Glazebrook, Karl +12 more
We investigate the properties of galaxies as they shut off star formation over the 4 billion years surrounding peak cosmic star formation. To do this, we categorize ∼7000 galaxies from 1 < z < 4 into 90 groups based on the shape of their spectral energy distributions (SEDs) and build composite SEDs with R ∼ 50 resolution. These composite SED…
Y Dwarf Trigonometric Parallaxes from the Spitzer Space Telescope
Cushing, Michael C.; Kirkpatrick, J. Davy; Gelino, Christopher R. +12 more
Y dwarfs provide a unique opportunity to study free-floating objects with masses <30 M Jup and atmospheric temperatures approaching those of known Jupiter-like exoplanets. Obtaining distances to these objects is an essential step toward characterizing their absolute physical properties. Using Spitzer’s Infrared Array Camera (IRAC) [4…