From hughes@astro.lsa.umich.edu Tue Apr 6 16:47:46 1999 Received: from ra.astro.lsa.umich.edu (ra.astro.lsa.umich.edu [141.211.104.2]) by chandra.bgsu.edu (980427.SGI.8.8.8/970903.SGI.AUTOCF) via ESMTP id QAA27815 for ; Tue, 6 Apr 1999 16:47:45 -0400 (EDT) Received: from mach.astro.lsa.umich.edu (mach.astro.lsa.umich.edu [141.211.105.67]) by ra.astro.lsa.umich.edu (8.9.1/8.9.1) with SMTP id QAA23837 for ; Tue, 6 Apr 1999 16:47:23 -0400 (EDT) From: "Philip A. Hughes" Date: Tue, 6 Apr 1999 16:47:22 -0400 Message-Id: <199904062047.QAA15392@mach.astro.lsa.umich.edu> To: gcd Subject: Re: latest version of html Status: RO Comer, a) Perhaps left justify the abstract text? b) Is it OK to lift the abstract material so directly from the text? I know it is "abstracting" material, but it seems to me to read a bit curiously when on starting the second paragraph of the proposal there is this sense of deja vu. c) Assuming point b) is not an issue, I suggest the following tweaks: Over the last decade the quantity and quality of images of extragalactic relativistic jets have increased to a point where it has become evident that curvature of light-year-scale flows is the norm, not the exception. Some of this curvature may be `apparent', resulting from a more modestly curved flow seen close to the line of sight. Nevertheless, such flows must posses some intrinsic curvature, and thus their 3-D morphology must be addressed. The study of such challenging phenomena demands fully 3D hydrodynamic simulation. The major focus of the present proposal for OSC resources is 3-D relativistic jet simulations using our Adaptive Mesh Refinement code. Over the last two years we have performed numerous tests on the code with the goal of making it as efficient as the underlying algorithms permit. The code is now ready to be used to perform research level simulations on the OSC Cray T94 and the Origin 2000 machines. The computational requirements of such simulations are significant in both memory and wall clock hours, and the 3-D simulations requested herein require facilities of the caliber of those at the OSC, principally due to the memory requirements. The present proposal requests OSC computing and visualization resources to study a number of relativistic jet problems: the nonlinear development of instabilities, the nature of jet internal structure, and the evolution of morphology and dynamics of both deflected and precessing 3-D relativistic jets. With the results of these simulations we can make major strides toward an understanding of the structure evident in bent jets, assess their stability, and through comparison with observational data, probe the internal physical conditions of such flows. d) If b) is an issue, I think we could cut out the preamble; the reader will meet it in the next paragraph anyway! Thus: The major focus of the present proposal for OSC resources is the simulation of relativistic jets using our 3D, Adaptive Mesh Refinement hydrodynamic code. Over the last two years we have performed numerous tests on the code with the goal of making it as efficient as the underlying algorithms permit. The code is now ready to be used to perform research level simulations on the OSC Cray T94 and the Origin 2000 machines. The computational requirements of such simulations are significant in both memory and wall clock hours, and the 3-D simulations requested herein require facilities of the caliber of those at the OSC, principally due to the memory requirements. The present proposal requests OSC computing and visualization resources to study a number of challenging relativistic jet problems: the nonlinear development of instabilities, the nature of jet internal structure, and the evolution of morphology and dynamics of both deflected and precessing 3-D relativistic jets. With the results of these simulations we can make major strides toward an understanding of the structure evident in bent jets, assess their stability, and through comparison with observational data, probe the internal physical conditions of such flows. --P