Search Publications
Empirically Constrained Predictions for Metal-line Emission from the Circumgalactic Medium
Schiminovich, David; Corlies, Lauren
The circumgalactic medium (CGM) is one of the remaining least constrained components of galaxies and as such has significant potential for advancing galaxy formation theories. In this work, we vary the extragalactic ultraviolet background for a high-resolution cosmological simulation of a Milky-Way-like galaxy and examine the effect on the absorpt…
An HST Proper-motion Study of the Large-scale Jet of 3C273
Anderson, Jay; Sparks, William B.; Georganopoulos, Markos +7 more
The radio galaxy 3C 273 hosts one of the nearest and best-studied powerful quasar jets. Having been imaged repeatedly by the Hubble Space Telescope (HST) over the past twenty years, it was chosen for an HST program to measure proper motions in the kiloparsec-scale resolved jets of nearby radio-loud active galaxies. The jet in 3C 273 is highly rela…
Ion Acceleration at the Quasi-parallel Bow Shock: Decoding the Signature of Injection
Burgess, D.; Sundberg, Torbjörn; Haynes, Christopher T. +1 more
Collisionless shocks are efficient particle accelerators. At Earth, ions with energies exceeding 100 keV are seen upstream of the bow shock when the magnetic geometry is quasi-parallel, and large-scale supernova remnant shocks can accelerate ions into cosmic-ray energies. This energization is attributed to diffusive shock acceleration however, for…
Young, Star-forming Galaxies and Their Local Counterparts: The Evolving Relationship of Mass-SFR-Metallicity Since z ∼ 2.1
Trump, Jonathan R.; Schneider, Donald P.; Gronwall, Caryl +5 more
We explore the evolution of the Stellar Mass-Star Formation Rate (SFR)-Metallicity relation using a set of 256 COSMOS and GOODS galaxies in the redshift range 1.90 < z < 2.35. We present the galaxies’ rest-frame optical emission-line fluxes derived from IR-grism spectroscopy with the Hubble Space Telescope and combine these data with SFRs an…
Angular Momentum Loss in the Envelope-Disk Transition Region of the HH 111 Protostellar System: Evidence for Magnetic Braking?
Lee, Chin-Fei; Li, Zhi-Yun; Hwang, Hsiang-Chih
HH 111 is a Class I protostellar system at a distance of ∼400 pc, with the central source VLA 1 associated with a rotating disk deeply embedded in a flattened envelope. Here we present the observations of this system at ∼0.″6 (240 au) resolution in C18O (J = 2 — 1) and a 230 GHz continuum obtained with the Atacama Large Millimeter/Submi…
High-Time Resolution In-situ Investigation of Major Cometary Volatiles around 67P/C-G at 3.1 - 2.3 AU Measured with ROSINA-RTOF
Wurz, P.; Bochsler, P.; Altwegg, K. +32 more
Comets considered to be pristine objects contain key information about the early formation of the solar system. Their volatile components can provide clues about the origin and evolution of gases and ices in the comets. Measurements with ROSINA/RTOF at 67P/Churyumov-Gerasimenko have now allowed, for the first time, a direct in situ high-time resol…
Reflection of Propagating Slow Magneto-acoustic Waves in Hot Coronal Loops: Multi-instrument Observations and Numerical Modeling
Van Doorsselaere, Tom; Pant, Vaibhav; Banerjee, Dipankar +3 more
Slow MHD waves are important tools for understanding coronal structures and dynamics. In this paper, we report a number of observations from the X-Ray Telescope (XRT) on board HINODE and Solar Dynamic Observatory/Atmospheric Imaging Assembly (AIA) of reflecting longitudinal waves in hot coronal loops. To our knowledge, this is the first report of …
Silicate Composition of the Interstellar Medium
Watson, D. M.; Sargent, B. A.; Fogerty, S. +2 more
The composition of silicate dust in the diffuse interstellar medium and in protoplanetary disks around young stars informs our understanding of the processing and evolution of the dust grains leading up to planet formation. An analysis of the well-known 9.7 µm feature indicates that small amorphous silicate grains represent a significant fra…
The Rhythm of Fairall 9. I. Observing the Spectral Variability with XMM-Newton and NuSTAR
Harrison, F. A.; Stern, D.; Zhang, W. W. +13 more
We present a multi-epoch X-ray spectral analysis of the Seyfert 1 galaxy Fairall 9. Our analysis shows that Fairall 9 displays unique spectral variability in that its ratio residuals to a simple absorbed power law in the 0.5-10 keV band remain constant with time in spite of large variations in flux. This behavior implies an unchanging source geome…
Multi-wavelength Study of the Supernova Remnant Kes 79 (G33.6+0.1): On Its Supernova Properties and Expansion into a Molecular Environment
Safi-Harb, Samar; Zhou, Ping; Zhang, Zhi-Yu +4 more
Kes 79 (G33.6+0.1) is an aspherical thermal composite supernova remnant (SNR) observed across the electromagnetic spectrum and showing an unusual highly structured morphology, in addition to harboring a central compact object (CCO). Using the CO J = 1-0, J = 2-1, and J = 3-2 data, we provide the first direct evidence and new morphological evidence…