tokens: by the region of the disk behind the inner rim. Detailed studies have indicated that the picture is somewhat more complicated, with intermediate-temperature components of uncertain origin (e.g., Fischer et al. 2011 ). For the purposes of this study, where we are taking a first look at time variability in the excess, we restrict ourselves to blackbody models of these three basic components, following McClure13 . Each component is defined by a characteristic blackbody temperature and solid angle. We fix the hot component temperature at 7000 K, which is characteristic of accretion shock emission (the exact value is not crucial here because we are seeing only the Rayleigh–Jeans tail). We also fix the cool component to a value of 600 K, which is roughly the equilibrium temperature for dust at the predicted location of the inner edge of the circumbinary disk around DQ Tau (∼2.5 a = 0.35 au). For the warm component, we allow the temperature to vary between 1000 and 1800 K (which spans the range of typical characteristic maximum dust temperatures in TTSs) in increments of 50 K. The solid angles (relative to the stellar value assuming R = 1.5 R ⊙ and d = 196 pc) are varied from 0 to 0.1 for the hot component, 10–50 for the warm component, and 50 to 300 in the cool component. For each set of parameters, the models for all three components are combined and then compared to the observed excess spectra, with the best fit determined via chi-squared minimization. The resulting best fits for each observed spectrum are shown in Figure 20 , with the associated parameters listed in Table 8 . Given the systematic uncertainties in the template matching, these values should be taken as indicative only; however, they provide a useful first look at the gross properties of the material in the inner regions of this system. The best-fit hot component solid angles range from zero at several epochs, where no discernible emission was detected, to 0.06, which is typical for weakly to moderately accreting TTSs. The cool component solid angles range from 90 to 260, roughly as expected for a puffed inner disk rim with a temperature of 600 K. If our assumption of a constant temperature is a reasonable approximation, the variation in solid angle may be indicative of a variable scale height of the inner edge of the putative circumbinary disk. There is a weak correlation with the warm component, but the origin of such a variation is unclear; it could simply be an artifact of our overly simplistic assumptions of the dust temperatures. However, it should be noted that this cooler dust emission is not as well-constrained as the other components because it contributes an appreciable fraction of the total emission only at the long-wavelength end of our spectra. Observations in the 5–10 μ m range are required to test the significance of any variations from this region. Figure 20. DQ Tau excess spectra shown in black, in order of observation time (left to right, top to bottom), with
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