Velocity and density spectra of the Small Magellanic Cloud

被引:144
作者
Stanimirovic, S
Lazarian, A
机构
[1] Cornell Univ, Nat Astron & Ionosphere Ctr, Arecibo Observ, Arecibo, PR 00612 USA
[2] Univ Wisconsin, Madison, WI 53706 USA
关键词
galaxies : individual (Small Magellanic Cloud); ISM : general; ISM : kinematics and dynamics; ISM : structure; turbulence;
D O I
10.1086/319837
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
This Letter reports results on the statistical analysis of H I turbulence in the Small Magellanic Cloud (SMC). We use 21 cm channel maps, obtained with the Australia Telescope Compact Array and the Parkes telescope, and analyze the spectrum of observed intensity fluctuations as a function of the velocity slice thickness. We confirm recent predictions by Lazarian & Pogosyan on the change of the power-law index and establish the spectra of three-dimensional density and velocity. The obtained spectral indices, -3.3 and -3.4, are slightly more shallow than the predictions for the Kolmogorov spectrum. This contrasts with the predictions for the shock-type spectra that are steeper than the Kolmogorov one. The nature of the energy injection in the SMC is unclear, as no distinct energy injection scales are observed up to the entire scale of the SMC.
引用
收藏
页码:L53 / L56
页数:4
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