Probing Kolmogorov turbulence beyond the Magellanic Clouds: The Power of Southern Hemisphere's largest optical telescope (11m), SALT

D. L. Block; B. G. Elmegreen; D. M. Elmegreen; I. Puerari

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arXiv · astro-ph/0402113

Probing Kolmogorov turbulence beyond the Magellanic Clouds: The Power of Southern Hemisphere's largest optical telescope (11m), SALT

D. L. Block·B. G. Elmegreen·D. M. Elmegreen·I. Puerari

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Abstract

The Hubble classification scheme of galaxies is based on blue-light appearance. Atlases reveal the rich variety of responses of the Population I component (`the mask') of gas and dust to the underlying, older, stellar population. However, the Population I component may only constitute 5 percent of the dynamical mass of the galaxy; furthermore, dusty masks are highly effective in hiding bars. We firstly discuss the rich duality in spiral structure, and highlight a near-infrared classification scheme for spiral galaxies. We next show that images secured with SALTICAM will be ideally suited to probe key questions such as whether the optical light in the gaseous Population I component is the result of Kolmogorov turbulence, cascasding from the largest of scales down to the Nyquist limit. If so, the optical emission in galaxies will be organized in a global fractal pattern with an intrinsic 1D power spectrum having a slope of -5/3, or -8/3 in 2D.

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D. L. Block, B. G. Elmegreen, D. M. Elmegreen, I. Puerari. 2004-02-04. Probing Kolmogorov turbulence beyond the Magellanic Clouds: The Power of Southern Hemisphere's largest optical telescope (11m), SALT. https://arxiv.org/abs/astro-ph/0402113

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