Search Publications
Challenging Some Contemporary Views of Coronal Mass Ejections. II. The Case for Absent Filaments
DeForest, C. E.; Howard, T. A.; Schneck, U. G. +1 more
When a coronal mass ejection (CME) appears in a coronagraph it often exhibits three parts. This “classic” three-part configuration consists of a bright leading edge, a dark circular- or teardrop-shaped cavity, and a bright core within the cavity. It is generally accepted that these are manifestations of coronal plasma pileup, the driving magnetic …
The Grism Lens-amplified Survey from Space (Glass). IX. The Dual Origin of Low-mass Cluster Galaxies as Revealed by New Structural Analyses
Schmidt, Kasper B.; Treu, Tommaso; Bradač, Maruša +10 more
Using deep Hubble Frontier Fields imaging and slitless spectroscopy from the Grism Survey from Space, we study 2200 cluster and 1748 field galaxies at 0.2≤slant z≤slant 0.7 to determine the impact of environment on galaxy size and structure at stellar masses {log}{M}* /{M}⊙ > 7.8, an unprecedented limit at these redshifts.…
Synchrotron Intensity Gradients as Tracers of Interstellar Magnetic Fields
Lee, Hyeseung; Yuen, Ka Ho; Cho, J. +1 more
On the basis of the modern understanding of MHD turbulence, we propose a new way of using synchrotron radiation: using synchrotron intensity gradients (SIGs) for tracing astrophysical magnetic fields. We successfully test the new technique using synthetic data obtained with 3D MHD simulations and provide the demonstration of the practical utility …
Critical Height of the Torus Instability in Two-ribbon Solar Flares
Wang, Yuming; Liu, Rui; Liu, Jiajia +5 more
We studied the background field for 60 two-ribbon flares of M-and-above classes during 2011-2015. These flares are categorized into two groups, I.e., eruptive and confined flares, based on whether a flare is associated with a coronal mass ejection or not. The background field of source active regions is approximated by a potential field extrapolat…
A Chemical Composition Survey of the Iron-complex Globular Cluster NGC 6273 (M19)
Clarkson, William I.; Caldwell, Nelson; Rich, R. Michael +5 more
Recent observations have shown that a growing number of the most massive Galactic globular clusters contain multiple populations of stars with different [Fe/H] and neutron-capture element abundances. NGC 6273 has only recently been recognized as a member of this “iron-complex” cluster class, and we provide here a chemical and kinematic analysis of…
Physical Properties of Sub-galactic Clumps at 0.5 ≤ Z ≤ 1.5 in the UVUDF
Grogin, Norman A.; Koekemoer, Anton M.; Ravindranath, Swara +8 more
We present an investigation of clumpy galaxies in the Hubble Ultra Deep Field at 0.5≤slant z≤slant 1.5 in the rest-frame far-ultraviolet (FUV) using Hubble Space Telescope Wide Field Camera 3 broadband imaging in F225W, F275W, and F336W. An analysis of 1404 galaxies yields 209 galaxies that host 403 kpc scale clumps. These host galaxies appear to …
Haro 11: Where is the Lyman Continuum Source?
Jaskot, Anne E.; James, Bethan L.; Oey, M. S. +1 more
Identifying the mechanism by which high-energy Lyman continuum (LyC) photons escaped from early galaxies is one of the most pressing questions in cosmic evolution. Haro 11 is the best known local LyC-leaking galaxy, providing an important opportunity to test our understanding of LyC escape. The observed LyC emission in this galaxy presumably origi…
Ionized Gas Outflows in Infrared-bright Dust-obscured Galaxies Selected with WISE and SDSS
Toba, Yoshiki; Nagao, Tohru; Wang, Wei-Hao +5 more
We present the ionized gas properties of infrared (IR)-bright dust-obscured galaxies (DOGs) that show an extreme optical/IR color, {(i-[22])}{AB}> 7.0, selected with the Sloan Digital Sky Survey (SDSS) and Wide-field Infrared Survey Explorer (WISE). For 36 IR-bright DOGs that show [O III]λ5007 emission in the SDSS spectra, we perform…
First Results from the KMOS Lens-Amplified Spectroscopic Survey (KLASS): Kinematics of Lensed Galaxies at Cosmic Noon
Fontana, Adriano; Schmidt, Kasper B.; Treu, Tommaso +12 more
We present the first results of the K-band Multi-Object Spectrometer (KMOS) Lens-Amplified Spectroscopic Survey, a new ESO Very Large Telescope large program, doing multi-object integral field spectroscopy of galaxies gravitationally lensed behind seven galaxy clusters selected from the Hubble Space Telescope (HST) Grism Lens-Amplified Survey from…
Spatially Resolved Kinematics in the Central 1 kpc of a Compact Star-forming Galaxy at z ∼2.3 from ALMA CO Observations
Rujopakarn, W.; Faber, S. M.; Dekel, A. +9 more
We present high spatial resolution (FWHM ∼ 0.″14) observations of the CO(8-7) line in GDS-14876, a compact star-forming galaxy at z = 2.3 with a total stellar mass of log(M ⋆/M ⊙) = 10.9. The spatially resolved velocity map of the inner r ≲ 1 kpc reveals a continuous velocity gradient consistent with the kinematics of a rotat…