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We present a Differential Emission Measure (DEM) analysis of the quiet solarcorona on disk using data obtained by the Extreme-ultraviolet ImagingSpectrometer (EIS) on {\it Hinode}. We show that the expected quiet Sun DEMdistribution can be recovered from judiciously selected lines, and that theiraverage intensities can be reproduced to within 30%. We present a subset ofthese selected lines spanning the temperature range $\log$ T = 5.6 to 6.4 Kthat can be used to derive the DEM distribution reliably. The subset can beused without the need for extensive measurements and the observed intensitiescan be reproduced to within the estimated uncertainty in the pre-launchcalibration of EIS. Furthermore, using this subset, we also demonstrate thatthe quiet coronal DEM distribution can be recovered on size scales down to thespatial resolution of the instrument (1$"$ pixels). The subset will thereforebe useful for studies of small-scale spatial inhomogeneities in the coronaltemperature structure, for example, in addition to studies requiring multipleDEM derivations in space or time. We apply the subset to 45 quiet Sun datasetstaken in the period 2007 January to April, and show that although the absolutemagnitude of the coronal DEM may scale with the amount of released energy, theshape of the distribution is very similar up to at least $\log$ T $\sim$ 6.2 Kin all cases. This result is consistent with the view that the {\it shape} ofthe quiet Sun DEM is mainly a function of the radiating and conductingproperties of the plasma and is fairly insensitive to the location and rate ofenergy deposition. This {\it universal} DEM may be sensitive to other factorssuch as loop geometry, flows, and the heating mechanism, but if so they cannotvary significantly from quiet Sun region to region.

Hinode/Extreme-Ultraviolet Imaging Spectrometer Observations of the Temperature Structure of the Quiet Corona