289 citations · 4.5k across the 121 of their papers we have counts for
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Fast dynamos in weakly ionized gases
Ellen G. Zweibel Fabian Heitsch
The turnover of interstellar gas on yr timescales argues for the continuous operation of a galactic dynamo. The conductivity of interstellar gas is so high that the dyna…
Evolution of Unmagnetized and Magnetized Shear Layers
M. L. Palotti, F. Heitsch, E. G. Zweibel +1
We present numerical simulations of the growth and saturation of the Kelvin-Helmholtz instability in a compressible fluid layer with and without a weak magnetic field. In the absen…
The Milky Way's Kiloparsec Scale Wind: A Hybrid Cosmic-Ray and Thermally Driven Outflow
John E. Everett, Ellen G. Zweibel, Robert A. Benjamin +4
We apply a wind model, driven by combined cosmic-ray and thermal-gas pressure, to the Milky Way, and show that the observed Galactic diffuse soft X-ray emission can be better expla…
Magnetic Fields in Irregular Galaxies
Amanda A. Kepley, Stefanie Muehle, Eric M. Wilcots +4
Magnetic fields are an important component of the interstellar medium, especially in low-mass galaxies like irregulars where the magnetic pressure may be significant. However, few…
Ideal Internal Kink Modes in a Line-tied Screw Pinch
Yi-Min Huang, Ellen G. Zweibel, Carl R. Sovinec
It is well known that the radial displacement of the internal kink mode in a periodic screw pinch has a steep jump at the resonant surface where …
The Weak Field Limit of the Magnetorotational Instability
Julian H. Krolik, Ellen G. Zweibel
We investigate the behavior of the magneto-rotational instability in the limit of extremely weak magnetic field, i.e., as the ratio of ion cyclotron frequency to orbital frequency…
Dust heating by the interstellar radiation field in models of turbulent molecular clouds
Thomas Bethell, Ellen Zweibel, Fabian Heitsch +1
We have calculated the radiation field, dust grain temperatures, and far infrared emissivity of numerical models of turbulent molecular clouds. When compared to a uniform cloud of…
Magnetoelliptic Instabilities
Norman R. Lebovitz, Ellen G. Zweibel
We consider the stability of a configuration consisting of a vertical magnetic field in a planar flow on elliptical streamlines in ideal hydromagnetics. In the absence of a magneti…
Magnetic Field Evolution in Neutron Star Crusts due to the Hall Effect and Ohmic Decay
Andrew Cumming, Phil Arras, Ellen G. Zweibel
We present calculations of magnetic field evolution by the Hall effect and Ohmic decay in neutron star crusts. We first discuss when and for which neutron stars the Hall effect is…
Kelvin-Helmholtz Instability in a Weakly Ionized Medium
C. Watson, E. G. Zweibel, F. Heitsch +1
Ambient interstellar material may become entrained in outflows from massive stars as a result of shear flow instabilities. We study the linear theory of the Kelvin - Helmholtz inst…
Turbulence in the Star-forming Interstellar Medium: Steps toward Constraining Theories with Observations
Mark Heyer, Ellen Zweibel
Increasingly sophisticated observational tools and techniques are now being developed for probing the nature of interstellar turbulence. At the same time, theoretical advances in u…
Turbulent Ambipolar Diffusion: Numerical Studies in 2D
F. Heitsch, E. G. Zweibel, A. D. Slyz +1
Under ideal MHD conditions the magnetic field strength should be correlated with density in the interstellar medium (ISM). However, observations indicate that this correlation is w…
Cosmic Ray History and its Implications for Galactic Magnetic Fields
Ellen G. Zweibel
There is evidence that cosmic rays were present in galaxies at moderately high redshift. This suggests that magnetic fields were also present. If cosmic rays and magnetic fields mu…
Fast Reconnection in a Two-Stage Process
Fabian Heitsch, Ellen G. Zweibel
Magnetic reconnection plays an essential role in the generation and evolution of astrophysical magnetic fields. The best tested and most robust reconnection theory is that of Parke…
Numerical Simulations of Magnetic Fields in Astrophysical Turbulence
Ellen G. Zweibel, Fabian Heitsch, Yuhong Fan
The generation and evolution of astrophysical magnetic fields occurs largely through the action of turbulence. In many situations, the magnetic field is strong enough to influence…
Ambipolar Drift in a Turbulent Medium
Ellen G. Zweibel
The interstellar magnetic field strength and gas density are observed to be correlated, but there is a large dispersion in this relation. In particular, the magnetic field is often…
Magnetic Field Diagnostics Based on Far-Infrared Polarimetry: Tests Using Numerical Simulations
F. Heitsch, E. G. Zweibel, M. -M. Mac Low +2
The dynamical state of star-forming molecular clouds cannot be understood without determining the structure and strength of their magnetic fields. Measurements of polarized far-inf…
Magnetic Screening in Accreting Neutron Stars
Andrew Cumming, Ellen G. Zweibel, Lars Bildsten
We investigate whether the magnetic field of an accreting neutron star may be diamagnetically screened by the accreted matter. We assume the freshly accumulated material is unmagne…
Fragmentation Instability of Molecular Clouds: Numerical Simulations
R. Indebetouw, E. G. Zweibel
We simulate fragmentation and gravitational collapse of cold, magnetized molecular clouds. We explore the nonlinear development of an instability mediated by ambipolar diffusion, i…
Generation of the Primordial Magnetic Fields during Cosmological Reionization
Nickolay Y. Gnedin, Andrea Ferrara, Ellen G. Zweibel
We investigate the generation of magnetic field by the Biermann battery in cosmological ionization fronts, using new simulations of the reionization of the universe by stars in pro…
Ambipolar Drift Heating in Turbulent Molecular Clouds
Paolo Padoan, ; Ellen Zweibel, ; AAke Nordlund
Although thermal pressure is unimportant dynamically in most molecular gas, the temperature is an important diagnostic of dynamical processes and physical conditions. This is the f…
Effects of Large-Scale Convection on p-mode Frequencies
M. Swisdak, E. Zweibel
We describe an approach for finding the eigenfrequencies of solar acoustic modes (p modes) in a convective envelope in the WKB limit. This approximation restricts us to examining t…