Bibliography: pages 141-143. / The direct reactions of pions with nuclei in the energy region of the πN(3,3) resonance are examined in the eikonal formalism. In particular, the angular and energy dependence of the elastic scattering of πsup(+-) from the calcium isotopes 40Ca, 48Ca is studied, using a detailed phenomenological approach. Excellent agreement is obtained with experimental data. A closely related investigation is also made of the inelastic excitation of low-lying collective states of 40Ca, 48Ca by pions. The resulting one-parameter fits yield deformation lengths which are compared with simple collective model predictions. The total cross-sections for neutral pion scattering from 40Ca, 48Ca in the resonance region are investigated as well, and predictions are made

Typical energy loss calcuations in AdS/CFT simulations use an initial condition of off-shell pairs of quarks placed back-to-back in the QGP, but a precise and theoretically motivated description of configuration does not exist. Quark virtuality can have noticeable effects on the rate of energy loss so a first principles calculation is needed for the early time behaviour of virtual particles soon after production. We use the Schwinger Keldysh formalism to calculate a perturbative expression for the Energy Momentum Tensor of hard partons created before the formation of the Quark Gluon Plasma. We propose this as a foundational model to use as an initial condition in jet energy loss calculations.

The colour glass condensate captures quantum chromodynamics in its application to high-energy collider experiments in the spirit of an effective field theory. In deeply inelastic lepton-hadron scattering experiments, as well as in hadron-hadron collisions, the internal degrees of freedom of in-state hadrons are dominated by a dense medium of gluonic matter called the colour glass condensate. Interactions with this medium by some (dilute) probe are most naturally described in terms of Wilson-lines and their correlators. The energy-dependence of these correlators is given by the JIMWLK (Jalilian-Marian+Iancu+McLerran+Weigert+Leonidov+Kovner) equa- tion which, when applied to a correlator, generates an infinite tower of coupled Dyson-Schwinger- like equations referred to as a Balitsky Hierarchy. In this thesis, I present a novel method for truncating, in a gauge-invariant and symmetry- preserving manner, the Balitsky hierarchy associated with matrices of Wilson-line correlators. This truncation is realized by parameterizing the energy-dependence of the symmetric and anti- symmetric parts of these matrices independently via energy-evolution operators which evolve ini- tial conditions in a manner akin to the time-evolution of Hermitian operators in the Heisenberg picture of quantum mechanics. These energy-evolution operators are path-ordered exponentials whose exponents are expanded in terms of energy-dependent "colour structure functions". I show how the properties of contributions to the expansion of these exponents (at each order in the expansion) are constrained by the group theory of SU(Nc).

We study the multiple radiative gluon emission off a massless and highly energetic quark in the pQCD picture. We introduce the Maximally Helicity Violating (MHV) techniques to cope with the complexities in computing cross sections in multi-jet QCD. The multiphoton emission in QED is reviewed to emphasize the efficiency of the MHV approach. We show that the computation of the multiple photon emission current provides insight into the understanding of the multiple radiative gluon emission in QCD. We then compute the momentum distribution for one, two and three soft and collinear radiative gluons from a hard struck quark. Our MHV results exhibit non-Abelian information about the correlation of gluons. As a phenomenological analysis, we study the energy spectrum for emitting radiative gluons using our MHV results. By comparing the MHV and the standard Poisson approximation of uncorrelated multiple emission results, we see that there is significant difference between the two methods.

No description available.

This thesis presents a series of results relating to conserved charges in general relativity. In particular, we give a general expression for a gravitational charge corresponding to a boost Killing vector. Further, we use Hamiltonian perturbative techniques to obtain generalizations of the first law of black hole mechanics pertaining to accelerated black holes, stationary Kaluza-Klein black holes and static Kaluza-Klein bubble spacetimes. Finally, we present a generalized Hamiltonian formulation of gravity adapted to a higher dimension splitting of spacetime, motivated by the physics of branes.

No description available.

No description available.

<p> [Co/Pd]<i>_n</i> multilayers with different number of repetitions n were deposited on Si substrates in order to study the magnetic properties and Hall resistivity in this system. The magnetic moment dependence on applied field was studied in parallel (in-plane) and perpendicular (out-of-plane) configurations. The [Co/Pd]<i>_n</i> multilayers with 2 and 3 repetitions, with thickness of the Co sublayer of 0.8 and 1.0 nm and thickness of the Pd sublayer of 1.3 and 2.0 nm, were found to have perpendicular magnetic anisotropy. The Hall resistivity dependence on applied field was measured at different temperatures. The Hall hysteresis loops confirm the perpendicular anisotropy of the multilayers, and indicate that the origin of the anomalous Hall effect (AHE) in this system, with low number of repetitions, is dominated by surface scattering.</p>

The CPLEAR experiment is a high precision experiment aiming to measure several CP violating parameters in the neutral kaon system. In order to decouple the errors on the phase angles of these parameters with the error on the KL- Ks mass difference (~m), the experiment will also make a measurement of ~m from semileptonic neutral kaon decays. This thesis describes a preliminary determination of ~m from a time dependent asymmetry in the semileptonic decays of tagged KOs and KOs. In order to select a sample of semileptonic decays it was necessary to develop a method of separating electron and pion tracks. The electromagnetic calorimeter can only separate electrons and pions at momenta above 200 MeVIc. In this thesis the development of a method of separating the two types of particle at momenta below 250 MeV[c is also described. From data collected between September 1990 and October 1991, a sample of 45000 semileptonic decays has been isolated and a value of the mass difference determined to be ~mhs = 0.477 ± 0.016(stat.) +-00..000014 } (syst.)