Joel E. Tohline

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As publishers establish a greater online presence as well as infrastructure to support the distribution of more varied information, the idea of an executable paper that enables greater interaction has developed. An executable paper provides more information for computational experiments and results than the text, tables, and figures of standard papers.(More)
Fourier-based approaches to calculate the Fresnel diffraction of light provide one of the most efficient algorithms for holographic computations because this permits the use of the fast Fourier transform (FFT). This research overcomes the limitations on sampling imposed by Fourier-based algorithms by the development of a fast shifted Fresnel transform. This(More)
Let's face it: The printed journal format that has served the scientific research community satisfactorily for more than 200 years doesn't serve the computational sciences community well at all. The community should, instead, communicate and archive the results of its research endeavors through a venue that lets students and colleagues fully examine(More)
R ecord keeping has always been an essential component of science and engineering, but it has become even more so recently. As computers get faster, we perform increasingly complex computa-tions—and as storage gets cheaper, we accumulate larger volumes of data. The complete process, from data acquisition through analysis, is inherently exploratory: users(More)
We model two mergers of orbiting binary neutron stars, the first forming a black hole and the second a differentially rotating neutron star. We extract gravitational waveforms in the wave zone. Comparisons to a post-Newtonian analysis allow us to compute the orbital kinematics, including trajectories and orbital eccentricities. We verify our code by(More)
We show that an exact expression for the GreenÏs function in cylindrical coordinates is 1 o x [ x@ o \ 1 nJRR@ ; m/~= = eim(Õ~Õ {)Q m~1@2 (s), where and is the half-integer degree Legendre function of the s 4 [R2]R@ 2 ](z[z@)2]/(2RR@), Q m~1@2 second kind. This expression is signiÐcantly more compact and easier to evaluate numerically than the more familiar(More)
We investigate the influence of magnetic fields upon the dynamics of, and resulting gravitational waves from, a binary neutron-star merger in full general relativity coupled to ideal magnetohydrodynamics. We consider two merger scenarios: one where the stars have aligned poloidal magnetic fields and one without. Both mergers result in a strongly(More)
The evolution of a neutron-star r-mode driven unstable by gravitational radiation is studied here using numerical solutions of the full nonlinear fluid equations. The dimensionless amplitude of the mode grows to order unity before strong shocks develop which quickly damp the mode. In this simulation the star loses about 40% of its initial angular momentum(More)