This paper describes the design and construction of the MicroBooNE liquid argon time projection chamber and associated systems. MicroBooNE is the first phase of the Short Baseline Neutrino program, located at Fermilab, and will utilize the capabilities of liquid argon detectors to examine a rich assortment of physics topics. In this document details of design specifications, assembly procedures, and acceptance tests are reported.

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A new technique sensitive to molecular orientation and geometry, and based on measuring the polarization of x-ray emission, has been applied to the Cl-containing molecules methyl chloride (CH3C1) and the chlorofiuoromethanes (CF3C1, CF,C12, and CFC13) in the gas phase. Upon selective excitation using monochromatic synchrotron radiation in the Cl K-edge (Cl 1s) near-threshold region, polarization-selectivex-ray emission studies reveal highly polarized molecular ualence x-ray Auorescence for all four molecules. The degree and the orientation of the polarized emission are observed to be sensitive to the incident excitation energy near the Cl K edge. In some cases, the polarization direction for x-ray emission reverses for small changes in incident excitation energy (a few eV). It is shown that the polarized x-ray emission technique can be used to infer, directly from experiment, symmetries of occupied and unoccupied valence molecular orbitals, anisotropies in absorption and emission, and orientational and geometrical information. It is suggested that the x-ray polarized-Auorescence phenomenon, reported here for simple molecules, can be used as a new approach to study more complicated systems in a variety of environments.

We present details of the theory and experimental observation of dynamical diffraction of x rays at grazing angle from crystal planes normal to a surface. We are able to associate different features of the specularly reAected and diffracted-reAected beam cruxes with the contributions from the a and P branches of the dispersion surfaces. The theory predicts surface propagation modes to which internal and external beams can couple only through the diffraction process. An experiment is described in which the specularly reAected and rejected-diffracted beams were simultaneously observed for 8-keV x rays incident on germanium. The agreement with first-order theory is good, but we observe systematic deviations. We present calculations that illustrate how eigenstates of thewave fields, which are x-ray standing waves with nodal planes normal to the surface of the crystal, can be used to obtain atomic registration at a surface or interface.