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\section{Introduction}  High-velocity clouds (HVCs) provide a unique window into the coolest component of the circumgalactic medium and the processes of Galactic inflow and outflow. HVCs, and the complexes into which they are arranged, are found by their emission in HI or absorption in numerous metal lines, and have radial velocities inconsistent with Galactic rotation \cite{Wakker_1997}. The precise origin for most HVCs is unknown, and some mix of Galactic wind, Galactic fountain, multiphase accretion, and gas stripping from satellites is typically invoked \cite{Putman_2012}. The exception is the Magellanic stream, which was stripped from the large and small Magellenic clouds, and which we will exclude from our discussion in this work. HVCs with negative radial velocities, which are metal enriched in the range of 10\% to 30\% of the solar metallicity, are likely a tracer of the process by which material accretes onto the Galaxy, though the total rate of this accretion is very uncertain. Less explored are the HVCs with positive radial velocities, most of which are in the inner two quadrants of the Galactic sky. These include the Wannier complexs complexes  WA, WB, WD, WE, and the Smith Cloud \cite{1991A&A...250..509W}. The Smith cloud has received significant attention of late, for its strongly cometary appearance which provides enough information to infer past trajectories, and make some inference as to its origin \cite{Lockman_2008, Fox_2015}. Complex WD is the largest area positive velocity HVC Complex, covering 310 square degrees with a total HI flux of 1.2 $\times 10^7$ K km/s arcmin$^2$, and a maximum HI column density of $\sim 1.2 \times 10^{20}$ cm$^{-2}$. It is by far the largest complex that exists in the inner two Galactic quadrants, where a small fraction of HVC flux is detected. With a range of velocities between +90 and +130 km/s, it is consistent with cylindrical rotation on the far side of the inner Galaxy, 20 kpc from the sun with a mass of 6 $\times 10^7 M_\odot$. This would make it very similar in mass, Galactocentric radius, and height to Complex C, the largest area and brightest HVC complex \cite{Thom_2008}. It is still unknown why there is a bias toward the outer disk in the HVC complexes, but determining the distance of this outlier object should significantly improve our understanding of the structure of the Milky Way's HVC system as a whole.  One major issue in gaining a better physical understanding these enigmatic clouds is their unknown distance. Since there are no objects of standard luminosity in HVCs, there are effectively no direct distance constraints. HI emission or optical and UV absorption lines toward extragalactic background sources only the distance-independent column densities. HVC distances would not only give us a masses for these structures, but also a context; the spatial relationship between the cloud and the nearby spatial and kinematic structure of the disk gives us insight as to its origin.  There are a number of indirect methods for measuring the distance to an HVC complex, including H$\alpha$ emission and kinematic structure \cite{Putman_2003, Peek_2007}, but the only proven direct distance measure is stellar absorption. By observing stars with measured distances at high spectral resolution, one can look for absorption lines in Na I, Ca II H & K, Ti II, and numerous ultraviolet absorption lines at the velocity of HI emission from HVCs \cite{1995A&A...302..364S}. By finding detections and non-detections of these absorption lines along lines of sight toward HI emitting HVCs, distances can be robustly measured. A number of clouds have well-measured distances using this method, but complex WD is not among them \cite{Wakker_2001, Wakker_2007, Thom_2008, Wakker_2008}.  In this work we report the first distance upper limit on Complex WD using absorption line spectroscopy toward a blue horizontal branch star. We extend the methods of \cite{Sirko_2004} to find the spectral type of a blue horizontal branch star, and thus put a precise distance limit. We use this to make some inferences as to the possible origin of Complex WD, and how it fits into the structure of Galactic HVCs as a whole.