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AMS instrument aboard the International Space Station is a high precision instrument capable of collecting large statistics on cosmic ray intensities and as such has started making highly significant contributions to Astroparticle Physics. In order to fully benefit from these observations, the positron fraction in cosmic rays in their recent publication and other results that will follow, the models to interpret the results have to be equally good. We enlarge on this remark by citing examples from the currently popular model and one of our own fitting the observed spectra of positrons, extending it to higher energies. We also show what one might expect to observe from a mono-energetic source, such as the annihilation of dark matter.

Decoherence effects at finite temperature (T) are examined for two manifestly quantum systems: (i) Casimir forces between parallel plates that conduct along different directions, and (ii) a topological Aharonov-Bohm (AB) type force between fluxons in a superconductor. As we illustrate, standard path integral calculations suggest that thermal effects may remove the angular dependence of the Casimir force in case (i) with a decoherence time set by h/(k_{B} T) where h is Plank's constant and k_{B} is the Boltzmann constant. This prediction may be tested. The effect in case (ii) is due a phase shift picked by unpaired electrons upon encircling an odd number of fluxons. In principle, this effect may lead to small modifications in Abrikosov lattices. While the AB forces exist at extremely low temperatures, we find that thermal decoherence may strongly suppress the topological force at experimentally pertinent finite temperatures. It is suggested that both cases (i) and (ii) (as well as other examples briefly sketched) are related to a quantum version of the fluctuation-dissipation theorem.

Cosmic rays are the highest energy particles available for our study and as such serve as excellent probes of the effects of Lorentz Invariance Violations, which are expected to increase with energy. This general paradigm is investigated in this paper by studying the effects of such violations within the Coleman-Glashow model in which each particle species may have its own maximum attainable velocity, even exceeding that of light \\textit{in vacuo}. The particular focus here is that the muon neutrino may have the maximum speed exceeding that of light. We show that such an assumption leads to the elongation of the decay lifetime of the pion that increases with energy over and above the time dilation effects. We provide a transparent analytical derivation of the spectral intensities of muon neutrinos and muons generated in the Earth's atmosphere by cosmic rays. In this derivation we not only account for elongation of the pion lifetime, but also for the loss of energy by the neutrinos by radiation of the electron-positron pairs through the Cohen-Glashow process, during their propagation. We then compare the theoretical spectra with observations of neutrinos and muons from large instruments like IceCube and BUST to set a limit of \\(\\sim10^{-13}\\) on the fractional excess speed of neutrinos over that of light. We also show that the ratio of the spectral intensities of downward and upward moving neutrinos at various angles constitute a diagnostic exclusively for the Cohen-Glashow process, which may be searched for in the IceCube data set. We conclude the paper with several comments, including those related to improvements of these tests when definite signals of GZK neutrinos will be observed.

First experimental measurements are presented for the kink instability in a linear plasma column which is insulated from an axial boundary by finite sheath resistivity. Instability threshold below the classical Kruskal-Shafranov threshold, axially asymmetric mode structure and rotation are observed. These are accurately reproduced by a recent kink theory, which includes axial plasma flow and one end of the plasma column that is free to move due to a non-line-tied boundary condition.

We have developed a torsion balance with a sensitivity about ten times better than those of previously operating balances for the study of long range forces coupling to baryon and lepton number. We present here the details of the design and expected characteristics of this balance. Operation of this balance for a year will also result in improved bounds on long range interactions of dark matter violating Einstein's equivalence principle.

In this paper we note that the spectral intensities of antiprotons observed in Galactic cosmic rays in the energy range ~ 1-100 GeV by BESS, PAMELA and AMS instruments display nearly the same spectral shape as that generated by primary cosmic rays through their interaction with matter in the interstellar medium, without any significant modifications. More importantly, a constant residence time of ~ 2.5 +/-0.7 million years in the Galactic volume, independent of the energy of cosmic rays, matches the observed intensities. A small additional component of secondary antiprotons in the energy below 10 GeV, generated in cocoon-like regions surrounding the cosmic-ray sources, seems to be present. We discuss this result in the context of observations of other secondary components like positrons and Boron, and conclude with general remarks about the origins and propagation of cosmic rays.

Plasma processing has become an integral part of the fabrication of integrated circuits since it offers advantages in the form of high selectivity, directionality, low processing temperatures, high yields, low hazardous material wastes and anisotropy. However, an ongoing problem with plasma processing is that of damage to the thin oxides in MOS devices. Two dominant mechanisms have been given as the cause of damage and these are plasma non-uniformity [1] in deposition and etching tools, and electron shading damage. Electron shading damage [1], [2] has been proposed to occur because of the large distribution angles of electrons as they leave the plasma sheath and ions having smaller angles which allow them to get into the small trenches and vias during metal etch and deposition. A large positive charge accumulates at the bottom of the trenches and a negative charge on the top. Due to these large charge imbalances, currents begin to tunnel through the thin oxides and damage them. Most of what is known about electron shading has been studied through theory and computer simulations. We have carried out a macroscopic, scaled experiment and computer modeling of the experiment to verify the existence of shading damage and to try and understand the role ions have in plasma damage. The scaling was done based on ratios of Debye lengths and particle collisions. The results of the experiment are compared with simulations that take into account the various plasma processes taking place in the plasma chamber.

We report here the results of operation of a torsion balance with a period of \\(\\sim 1.27 \\times 10^4\\) s. The analysis of data collected over a period of \\(\\sim\\)115 days shows that the difference in the accelerations towards the Galactic Center of test bodies made of aluminum and quartz was \\((0.61 \\pm 1.27) \\times 10^{-15} \\, \\mathrm{ m \\, s}^{-2}\\). This sets a bound on the violation of the equivalence principle by forces exerted by Galactic dark matter which is expressed by the E\"otv\"os parameter \\(\\eta_{DM} = (1.32 \\pm 2.68) \\times 10^{-5}\\), a significant improvement upon earlier bounds.