Effect of realignment on detachment in DIII-D small angle slot divertor

Analysis using the newly aligned small angle slot (SAS) divertor shows robustness of detachment onset to small divertor misalignments. The toroidal alignment of the SAS divertor in DIII-D was recently improved with respect to the outer strike point (OSP) location, as confirmed by toroidally separated Langmuir probes. Preliminary analysis of matched pre- and post-alignment discharges shows no significant difference in detachment onset for the OSP in the outer divertor corner. Detachment onset is rapid and observed across diagnostics for discharges with ion $\nabla B$ drift into the SAS; detachment onsets at $n_e\approx 6.0\times10^{13}$ cm$^{-3}$ pre-alignment, and $\approx 6.0-6.6\times10^{13}$ cm$^{-3}$ post-alignment. For ion $\nabla B$ drift out of the divertor, target $J_{sat}$ measured in the near scrape off layer rolls over at $n_e\approx 4.7\times 10^{13}$ cm$^{-3}$ in both pre- and post-alignment discharges. Probe-measured $T_e$ drops from $\approx 17$ eV at $\approx 3.7\times 10^{13}$ cm$^{-3}$; pre-alignment $T_e$ drops immediately to $<10$ eV but post-alignment $T_e$ drops more slowly to $<10$ eV near $J_{sat}$ rollover. These observations suggest that local variations in divertor conditions may have little effect on global detachment.