  Observations of Galactic H I gas for seven targeted regions at intermediate
Galactic latitude are presented at 1' angular resolution using data from the
DRAO Synthesis Telescope (ST) and the Green Bank Telescope (GBT). The DHIGLS
data are the most extensive arcminute resolution measurements of the diffuse
atomic interstellar medium beyond those in the Galactic plane. The acquisition,
reduction, calibration, and mosaicking of the DRAO ST data and the cross
calibration and incorporation of the short-spacing information from the GBT are
described. The high quality of the resulting DHIGLS products enables a variety
of new studies in directions of low Galactic column density. We analyze the
angular power spectra of maps of the integrated H I emission (column density)
from the data cubes for several distinct velocity ranges. Fitting power
spectrum models based on a power law, but including the effects of the
synthesized beam and noise at high spatial frequencies, we find exponents
ranging from -2.5 to -3.0.. Power spectra of maps of the centroid velocity for
these components give similar results. These exponents are interpreted as being
representative of the 3D density and 3D velocity fields of the atomic gas,
respectively. We find evidence for dramatic changes in the H I structures in
channel maps over even small changes in velocity. This narrow line emission has
counterparts in absorption spectra against bright background radio sources,
quantifying that the gas is cold and dense and can be identified as the cold
neutral medium phase. Fully reduced DHIGLS H I data cubes and other data
products are available at www.cita.utoronto.ca/DHIGLS.
