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We present contemporaneous XMM-Newton X-ray and ground-based optical/near-IRspectroscopic observations of the nearby ($D \approx 42$ pc), low-mass (mid-M)binary system TWA 30A and 30B. The components of this wide (separation$\sim$3400 AU) binary are notable for their nearly edge-on disk viewinggeometries, high levels of variability, and evidence for collimated stellaroutflows. We obtained XMM-Newton X-ray observations of TWA 30A and 30B in 2011June and July, accompanied (respectively) by IRTF SpeX (near-IR) and VLTXSHOOTER (visible/near-IR) spectroscopy obtained within $\sim$20 hours of theX-ray observations. TWA 30A was detected in both XMM-Newton observations atrelatively faint intrinsic X-ray luminosities ($L_{X}$$\sim$$8\times10^{27}$$erg$ $s^{-1}$) compared to stars of similar mass and age . The intrinsic(0.15-2.0 keV) X-ray luminosities measured in 2011 had decreased by a factor20-100 relative to a 1990 (ROSAT) X-ray detection. TWA 30B was not detected,and we infer an upper limit of ($L_{X}$ $\lesssim$ 3.0 $\times$ $10^{27}$ ergs$^{-1}$). We measured a large change in visual extinction toward TWA 30A (from$A_V \approx 14.9$ to $A_V \approx 4.7$) between the two 2011 observing epochs,and we find evidence for a corresponding significant decrease in X-rayabsorbing column ($N_H$). The apparent correlated change in $A_V$ and $N_H$ issuggestive of variable obscuration of the stellar photosphere by disk materialcomposed of both gas and dust. However, in both observations, the inferred$N_{H}$ to $A_{V}$ ratio is lower than that typical of the ISM, suggesting thatthe disk is either depleted of gas or is deficient in metals in the gas phase.

Evidence for Variable, Correlated X-ray and Optical/IR Extinction toward the Nearby, Pre-main Sequence Binary TWA 30