We present measurements of the spin-orbit alignment angle, λ, for the hot Jupiter systems WASP-32, WASP-38, and HAT-P-27/WASP-40, based on data obtained using the HARPS spectrograph. We analyze the Rossiter-McLaughlin effect for all three systems and also carry out Doppler tomography for WASP-32 and WASP-38. We find that WASP-32 (T eff = 6140+90 – 100 K) is aligned, with an alignment angle of λ = 105 + 6.4 – 6.5 obtained through tomography, and that WASP-38 (T eff = 6180+40 – 60 K) is also aligned, with tomographic analysis yielding λ = 75 + 4.7 – 6.1. The latter result provides an order-of-magnitude improvement in the uncertainty in λ compared to the previous analysis of Simpson et al. We are only able to loosely constrain the angle for HAT-P-27/WASP-40 (T eff = 5190+160 – 170 K) to λ = 242 + 76.0 – 44.5, owing to the poor signal-to-noise ratio of our data. We consider this result a non-detection under a slightly updated version of the alignment test of Brown et al. We place our results in the context of the full sample of spin-orbit alignment measurements, finding that they provide further support for previously established trends.
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