We present a power spectrum analysis of interferometric 21 cm observations of the Ursa Major high-latitude cirrus , obtained with the Dominion Radio Astrophysical Observatory ( DRAO ) of Penticton ( Canada ) .
These high-resolution data reveal the intricate structure of the diffuse Galactic Hi , at angular scales from 1 arcminute to 3 degrees .
A filtering method based on a wavelet decomposition was used to enhance the signal-to-noise ratio of the data .
The power spectra of the integrated emission and of the centroid velocity fields were used to deduce the three-dimensional ( 3D ) spectral index of the density and velocity fields of the Hi cirrus .
The spectral index is similar for the 3D density and velocity fields with a value of -3.6 \pm 0.2 .
Using the Leiden/Dwingeloo observations , this analysis was extended to the whole North Celestial Loop ( which includes the Ursa Major cirrus ) , showing that the scaling laws prevail from 0.1 to 25 pc .
The centroid velocity and integrated emission fields show moderate correlation , with a maximum cross-correlation value of 0.44 .