Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

Random-matrix theories in quantum physics : common concepts

We review the development of random-matrix theory (RMT) during the last decade. We emphasize both the theoretical aspects, and the application of the theory to a number of fields. These comprise chaotic and disordered systems, the localization problem, many-body quantum systems, the Calogero-Sutherland model, chiral symmetry breaking in QCD, and quantum gravity in two dimensions. The review is preceded by a brief historical survey of the developments of RMT and of localization theory since their inception. We emphasize the concepts common to the above-mentioned fields as well as the great diversity of RMT. In view of the universality of RMT, we suggest that the current development signals the emergence of a new "statistical mechanics": Stochasticity and general symmetry requirements lead to universal laws not based on dynamical principles.

Random Matrix Theories in Quantum Physics: Common Concepts

Nuclear forces can be systematically derived using effective chiral Lagrangians consistent with the symmetries of QCD. I review the status of the calculations for two- and three-nucleon forces and their applications in few-nucleon systems. I also address issues like the quark mass dependence of the nuclear forces and resonance saturation for four-nucleon operators.

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Modern theory of nuclear forces

Relativistic mean field theory in finite nuclei

A Meson Exchange Model for the Hyperon Nucleon Interaction

We investigate the structure of the nucleon resonance N^*(1440) (Roper) within a coupled-channel meson exchange model for pion-nucleon scattering. The coupling to pipiN states is realized effectively by the coupling to the sigmaN, piDelta and rhoN channels. The interaction within and between these channels is derived from an effective Lagrangian based on a chirally symmetric Lagrangian, which is supplemented by well known terms for the coupling of the Delta isobar, the omega meson and the 'sigma', which is the name given here to the strong correlation of two pions in the scalar-isoscalar channel. In this model the Roper resonance can be described by meson-baryon dynamics alone; no genuine N^*(1440) (3 quark) resonance is needed in order to fit piN phase shifts and inelasticities.

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What is the structure of the Roper resonance

We investigate the structure of the scalar mesons ${\mathit{f}}_{0}$(980) and ${\mathit{a}}_{0}$(980) within realistic meson-exchange models of the \ensuremath{\pi}\ensuremath{\pi} and \ensuremath{\pi}\ensuremath{\eta} interactions. Starting from a modified version of the J\"ulich model for \ensuremath{\pi}\ensuremath{\pi} scattering we perform an analysis of the pole structure of the resulting scattering amplitude and find, in contrast with existing models, a somewhat large mass for the ${\mathit{f}}_{0}$(980) (${\mathit{m}}_{\mathit{f}0}$=1015 MeV, ${\mathrm{\ensuremath{\Gamma}}}_{\mathit{f}0}$=30 MeV). It is shown that our model provides a description of J/\ensuremath{\psi}\ensuremath{\rightarrow}\ensuremath{\varphi}\ensuremath{\pi}\ensuremath{\pi}/\ensuremath{\varphi}KK data comparable in quality with those of alternative models. Furthermore, the formalism developed for the \ensuremath{\pi}\ensuremath{\pi} system is consistently extended to the \ensuremath{\pi}\ensuremath{\eta} interaction leading to a description of the ${\mathit{a}}_{0}$(980) as a dynamically generated threshold effect (which is therefore neither a conventional qq\ifmmode\bar\else\textasciimacron\fi{} state nor a KK\ifmmode\bar\else\textasciimacron\fi{} bound state). Exploring the corresponding pole position the ${\mathit{a}}_{0}$(980) is found to be rather broad (${\mathit{m}}_{\mathit{a}0}$=991 MeV, ${\mathrm{\ensuremath{\Gamma}}}_{\mathit{a}0}$=202 MeV). The experimentally observed smaller width results from the influence of the nearby KK\ifmmode\bar\else\textasciimacron\fi{} threshold on this pole.

J. Speth

Papers

A Meson Exchange Model for the Hyperon Nucleon Interaction

What is the structure of the Roper resonance

Structure of the scalar mesons f0(980) and a0(980).

Meson-exchange hyperon-nucleon interactions in free scattering and nuclear matter

The nuclear response within extended RPA theories