The HETG observation was done in CC mode, with the zero order offset so as to be barely on the CCD. As a result, the MEG -1 and HEG +1 orders are largely off the ACIS-S array, and there is little data there. The HEG-1 and MEG+1 orders seem to be OK, though -- note that these are rows 3 and 10 in the standard pha2 file. They also seem to have data that agree with each other, unlike adding in the semi-data in the other orders. So I'm going to focus on these two.
Fitting them with a tbabs*diskbb model gives a decent, if not great, fit (chi^2 ~ 1.8) between 1.5-6 keV:
nH 10^22 cm^-2 3.17742 +/- 3.18579E-03
Tin keV 2.12996 +/- 3.11115E-03
norm 114.390 +/- 0.645348
flux(0.3-10 keV) = 2.705e-08 ergs/cm^2/s
However, as the spectrum shows, the fit is pretty bad below 1.5 keV and above 6 keV. There isn't that much flux above 6 keV, and it won't make for much of a halo, so that can be ignored. However, the soft flux below 1.5 keV should be better fit. I don't know if it's even real, though - definitely a question for Norbert.
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