The Relativistic Heavy Ion Collider (RHIC), as the world's first and only polarized proton collider, offers a unique environment in which to study the spin structure of the proton. In order to study the proton's transverse spin structure, the PHENIX experiment at RHIC took data with transversely polarized beams in 2001-02 and 2005, and it has plans for further running with transverse polarization in 2006 and beyond. Results from early running as well as prospective measurements for the future will be discussed.

The electron transport through an array of tunnel junctions consisting of an STM tip and a granular film is studied both theoretically and experimentally. When the tunnel resistance between the tip and a granule on the surface is much larger than those between granules, a bottleneck of the tunneling current is created in the array. It is shown that the period of the Coulomb staircase(CS) is given by the capacitance at the bottleneck. Our STM experiments on Co-Al-O granular films show the CS with a single period at room temperature. This provides a new possibility for single-electron-spinelectronic devices at room temperature.Charging effects on single electron tunneling such as Coulomb blockade and Coulomb oscillation have attracted much interest [1]. Recent advances in nanotechnology enable us to fabricate small tunnel junctions where charging effects play an essential role. The I-V characteristics for double tunnel junction systems have been extensively studied, where the step-like structure called Coulomb staircase(CS) is observed when the resistances between the junctions are not equal [1]. For these asymmetric double junction systems, the junction with a large resistance behaves like a bottleneck of the tunneling current and the central island is charged through the other junction up to the maximum charge. The tunneling current jumps when the maximum charge changes. Recently, the CS has been observed by using a tip of scanning tunneling microscope(STM) of nanometer-size in highly resistive granular films [2-5] as well as metaldroplet systems [6,7]. For a granular film, which is considered to be an array of tunnel junctions, the observed CS implies that a bottleneck exists in the conducting paths. However, the physics behind the CS in a granular film is not clear because it contains many granules with different size and the conducting path may form a three-dimensional network in a thick granular film.Bar-Sadeh et al. have studied the STM current through a nonmagnetic granular film, Au-Al 2 O 3 , by using the cryogenic STM [2,3]. They observed the CS at temperatures T = 4.2 and 78 K, and analyzed the experimental data by using a triple barrier model. They assumed that the rate for tunneling between two granules is small and the number of excess electrons in each granule is treated independently. Because of these assumptions, the CS was given by the superposition of two different periods in their model: one was determined by the tunnel process between the STM tip and a granule, the other between another granule and the base electrode. On the contrary, as we will show later, the CS has a single period which is determined by the capacitance at the bottleneck.In this Letter, we study the electron transport through an array of tunnel junctions consisting of an STM tip and a granular film both theoretically and experimentally. In this system, we can vary the tunnel resistance between the tip and a granule on the surface by changing the distance between them. When the tunnel resistance between the tip and a granule ...

The problem of communication in the sea has been considered by many writers. They regarded the sea as a two-layered media, and the bottom of the sea bas not been included. However, the effect of the sea bottom cannot be neglected in some situations, for example in the case of.a'low frequency, a shallow sea, and the access of a transmitter or receiver to the sea bottom. The effect of the sea bottom on radio wave propagation is ascertained theoretically, and it will act as an important part in such cases. Considering a threelayered sea, the multipath reflection and multilateral waves that cannot be generated in a two-layered media are obtained.

We have investigated single electron tunneling in Co–Al–O and Cu–Al–O granular films using scanning tunneling microscopy (STM). Topographic images show well-defined granular structures where nanometer-sized metal granules are embedded in insulating matrix. The Coulomb staircases in the current–voltage (I–V) curves are clearly observed even at room temperature in both films. For the Co–Al–O film, furthermore, negative differential conductance appears in the Coulomb staircase.

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