VELOCITY SPECTRUM FOR HI AT HIGH LATITUDES

In this paper, we present the results of the statistical analysis of high-latitude Hi turbulence in the Milky Way. We have observed Hi in the 21 cm line, obtained with the Arecibo(3) L-Band Feed Array receiver at the Arecibo radio telescope. For recovering velocity statistics, we have used the velocity coordinate spectrum (VCS) technique. In our analysis, we have used direct fitting of the VCS model, as its asymptotic regimes are questionable for Arecibo's resolution, given the restrictions from thermal smoothing of the turbulent line. We have obtained a velocity spectral index of 3.87 +/- 0.11, an injection scale of 140 +/- 80 pc, and an Hi cold phase temperature of 52 +/- 11 K. The spectral index is steeper than the Kolmogorov index and can be interpreted as being due to shock-dominated turbulence.