Coded aperture imaging of fusion source in a plasma focus operated with pure D2 and a D2-Kr gas admixture Time-integrated measurements of fusion-produced protons emitted from PF-facilities AIP Conf. Proc. 812, 237 (2006); 10.1063/1.2168831 A_ measurement of S_pin-T_R_ansfer coefficients I_n the fusion reaction D_(d⃗, p⃗)3H (ASTRID) at 55 keV AIP Conf.Abstract. Protons from the fusion reactions D( 3 He,p) 4 He and D(d,p) 3 H have been observed in a small plasma focus device operated with a 3 He-D 2 gas mixture. The partial pressures of the 3 He and D 2 gasses were in the ratio of 2:1, corresponding to an atomic number ratio of 1:1. Two groups of protons with energies of approximately 16MeV and 3MeV arising from the D( 3 He,p) 4 He and D(d,p) 3 H reactions, were recorded simultaneously using a double-layer arrangement of CR-39 polymer nuclear track detectors (each of thickness 1000μm). As a result of the very different ranges of 16MeV and 3MeV protons, and the particle registration properties of CR-39, the D(d,p) 3 H protons were registered on the front-most CR-39 surface and the D( 3 He,p) 4 He protons were registered on the back-most surface of this double-layer configuration. A pinhole camera, containing the CR-39 detectors, was situated on the forward plasma focus axis in order to image the emission zones of protons for both fusion reactions. It was found that the D( 3 He,p) 4 He and D(d,p) 3 H proton yields were of similar magnitude, but their spatial distributions were very different. Results indicate that the D( 3 He,p) 4 He fusion was concentrated close to the plasma focus pinch column, while the D(d,p) 3 H fusion occurred at some distance from the pinch. Moreover, it appears that both the D( 3 He,p) 4 He and D(d,p) 3 H fusion yields are produced by beam-target mechanisms, with no significant thermonuclear contribution. To better understand the shape of the D(d,p) 3 H distribution, comparative experiments were performed with both a 4 He-D 2 gas mixture and pure D 2 gas. The D(d,p) 3 H distributions obtained for the 3 He-D 2 and 4 He-D 2 cases were found to be very similar, but markedly different from that obtained with pure D 2 gas. Possible explanations of these measured distributions are discussed.

We use a double-well optical lattice as an atom interferometer to load and measure atomic number-squeezed states with N = 1 or 2 and Poissonian states with N ≈ 1 into the lattice ground state.The optical beam splitter, with its two input and two output modes, is one of the simplest examples of a twomode quantum system. This system becomes even richer when the particles interact. Several experiments have demonstrated the macroscopic splitting of a trapped Bose-Einstein condensate (BEC) by raising a barrier to separate the condensate into two independent condensates [1,2,3]. In these experiments the number of atoms is large-not in a regime where few-particle quantum interference effects can be seen. We have demonstrated a few-atom quantum beam splitter and used it to create and analyze different classical and nonclassical states. The ability to create and analyze such states provides a platform for studying fundamental few-particle interacting systems, a probe of manybody states in a lattice, and is of paramount importance for quantum computation with neutral atoms.We realize an atomic analog of the two-mode quantum beam splitter with Bose-condensed 87 Rb atoms in the |F = 1, m F = −1 hyperfine state loaded into a double-well optical lattice [4]. This lattice has a unit cell that can be dynamically transformed between a single site configuration (the "λ-lattice") and a double-well configuration (the "λ/2-lattice"). In analogy with optical two-mode systems, the modes in this lattice are either the ground |g and first excited |e state of the single site configuration or the ground state of the left |L and right |R sites of the doublewell configuration. Dynamically switching between these two configurations acts as the "beam splitter."The speed at which the beam splitter is applied to the atomic cloud determines whether interactions will play a role in the beam splitting. If the beam splitter is applied quickly with respect to interaction energies, the interactions do not play a role in the occupation statistics of the output modes. This "non-interacting" (NI) beam splitter is analogous to the linear optics case: atoms in a single input mode (for example, |g ) are divided into the two appropriate output modes (here, |L and |R ) according to binomial statistics. In contrast if the beam splitter is applied slowly with respect to interaction energies, the interactions influence the output states. This "interacting" (I) beam splitter has no simple optical analog.We probe these states by using a method analogous to Mach-Zehnder (MZ) atom interferometry. The first beam splitter in the MZ interferometer is a NI beam splitter which symmetrically and coherently splits a single lattice site into a double-well. Atoms in individual sites of a double-well evolve independently for some time, analogous to the individual arms of an interferometer. In place of the second beam splitter we interfere the two paths by releasing the atoms and allowing them to expand and overlap in time-of-flight (TOF). The interference of the matter wave f...