John Blondin is a Professor of Physics at the North Carolina State University. He is carrying out research in the field of Circumstellar Gas-Dynamics using the time-dependent hydrodynamics code VH-1. His work covers a vast array of objects observed by astronomers both from ground-based observatories and from orbiting satellites. The two primary subjects under investigation are interacting binary stars including normal stars like the Algol binary, and compact object systems like the high mass X-ray binary SMC X-1 and supernova remnants from very young, like SNR 1987a, to older remnants like the Cygnus Loop. Other astrophysical processes of current interest include radiatively driven winds from hot stars, the interaction of stellar winds with the interstellar medium, the stability of radiative shockwaves, the propagation of jets from young stellar objects, and the formation of globular clusters.

Professor Blondin participated in the Terascale Supernova Initiative, an effort sponsored by the DOE SciDAC program to understand the mechanism behind core-collapse supernovae. Visualization of time-dependent datasets generated by large, threenism for creating the rapid spins of observed radio pulsars [1]. The new model he is developing includes substantially more physics in 3D and will generate hundreds of terabytes to several petabytes of dimensional simulations is a key component of this hunt to discover the mechanism behind core-collapse supernovae, the violent death of short-lived massive stars. As examples, visualization played a key role in understanding the origin of a dynamical instability of the supernova shock wave at an age of less than one second. This spherical accretion shock instability, or SASI, shown in Figure 1, is driven by the response of an initially spherical shock wave to global acoustic modes trapped in the interior. This instability, discovered in the early stages of TSI, provides a natural explanation for the asymmetry observed in most core-collapse supernovae. Following these 3D supernova models to later time, visualization of a spiral flow generated by the SASI led to the discovery of a new mechanism for creating the rapid spins of observed radio pulsars [1]. The new model he is developing includes substantially more physics in 3D and will generate hundreds of terabytes to several petabytes of data from one simulation. His approach is to create complex models involving all relevant physical processes and a wide range of time and length scales, using the largest computing platforms available. This process is one of discovery, where he is hunting for new clues generated in a virtual laboratory within a supercomputer. As such, this work demands interactive visualization, where one can quickly visualize different combinations of variables (scalars and vectors) or isolate features by manipulating the transparency of the rendered data. The dynamical nature of this problem also demands the ability to quickly produce animations from a time-series of 3D data. But whatever visualization technique is employed, it is clearthat the key to scientific discovery is interactive visualization of the data.

Volume visualization of angular momentum

Time step 1306

Time step 1345

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If you publish your work using this data set, please make acknowledgment of VisFiles: The data set is made available by Dr. John Blondin at the North Carolina State University through US Department of Energy's SciDAC Institute for Ultrascale Visuaization.

[Supernova Data]

 
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