Bose-Einstein Correlations from Opaque Sources

Bose-Einstein correlations in relativistic heavy ion collisions are very different for opaque sources than fortransparent ones. The Bose-Einstein radius parameters measured in two-particle correlation functions depend sensitively on the mean free path of the particles. In particular we find that the outward radius for an opaque source is smaller than the sidewards radius for sufficiently short duration of emission. A long duration of emission can compensate the opacity reduction of the longitudinal radius parameter and explain the experimental measurements of very similar side- and outward radius parameters.Comment: additional material included, 8 pages, revtex, epsfig, 2 figure included, manuscript also available at http://www.nbi.dk/~vischer/publications.htm

Fluctuations and HBT Scales in Relativistic Nuclear Collisions

Bose-Einstein correlations in relativistic heavy ion collisions are examined in a general model containing the essential features of hydrodynamical, cascade as well as other models commonly employed for describing the particle freeze-out. In particular the effects of longitudinal and transverse expansion, emission from surfaces moving in time, the thickness of the emitting layer varying from surface to volume emission and other effects are studied. Model dependences of freeze-out sizes and times are discussed and compared to recent $Pb+Pb$ data at 160A$\cdot$GeV.Comment: 9 pages, revtex, epsfig, 2 figure included, manuscript also available at http://www.nbi.dk/~vischer/publications.htm

Dynamical Formation of Disoriented Chiral Condensates

We study the dynamical formation of disoriented chiral condensates in very high energy nucleus-nucleus collisions using Bjorken hydrodynamics and relativistic nucleation theory. It is the dynamics of the first order confinement phase transition which controls the evolution of the system. Every bubble or fluctuation of the new, hadronic, phase obtains its own chiral condensate with a probability determined by the Boltzmann weight of the finite temperature effective potential of the linear sigma model. We evaluate domain size and chiral angle distributions, which can be used as initial conditions for the solution of semiclassical field equations.Comment: 17 pages, latex and 10 ps figures available at http://www.nbi.dk/~vischer/dcc.htm

Properties of exotic matter for heavy ion searches

We examine the properties of both forms of strange matter, small lumps of strange quark matter (strangelets) and of strange hadronic matter (Metastable Exotic Multihypernuclear Objects: MEMOs) and their relevance for present and future heavy ion searches. The strong and weak decays are discussed separately to distinguish between long-lived and short-lived candidates where the former ones are detectable in present heavy ion experiments while the latter ones in future heavy ion experiments, respectively. We find some long-lived strangelet candidates which are highly negatively charged with a mass to charge ratio like a anti deuteron (M/Z 2) but masses of A=10 to 16. We predict also many short-lived candidates, both in quark and in hadronic form, which can be highly charged. Purely hyperonic nuclei like the (2 02 ) are bound and have a negative charge while carrying a positive baryon number. We demonstrate also that multiply charmed exotics (charmlets) might be bound and can be produced at future heavy ion colliders

Children of the black patola stone : origin structures in a domain on Palu'e Island (Eastern Indonesia)

This thesis investigates the social and ceremonial order of one of twelve domains on Palu'e, a small volcanic island in Eastern Indonesia. Domains are identified as individual ceremonial, political and territorial units that are linked with each other in a system of ceremonial and political alliance, and enmity. Each domain is constituted by its ceremonial centre of which a senior member of a first settling group is the guardian. Within the domain first settling groups maintain a position of precedence over subsequently settling groups. Every domain conducts its own ceremonial cycle, at various stages of which narratives of origin are recited at the ceremonial centre. First settling groups hold the knowledge of these narratives. In these narratives the origins of the first settling groups and those of the island are conflated. Through the appropriation and manipulation of such origin structures, the first settling groups of a domain maintain a position of precedence, whereby later settling groups model themselves after the first settlers. This thesis examines the origin structures of the domain and the ideas that the people of the domain hold about those structures. In this process the social and ceremonial order of the domain is exposed

Relativistic field-theoretical transport in condensed matter

We discuss a relativistic transport theory of condensed matter based on a microscopic system containing bosonic and fermionic degrees of freedom interacting via 3 - and 4-point interactions. We use the Dyson hierarchy as a solution to the underlying field theory and truncate this hierarchy by parametrizing the 2-particle-irreducible kernels of the 4- and 5-point vertex functions. We then perform a complete crossing-symmetric reduction of the 2-particle intermediate states of the theory. We obtain a reduction hierarchy and show how to explore the quality of our truncation scheme using this reduction hierarchy. Finally we discuss the problem of regularization of the theory in the case of hadronic matter by either putting form factors directly in the action or by using dispersion relations to introduce causal form factors into singular diagrams

Visualization of SpoVAEa Protein Dynamics in Dormant Spores of <i>Bacillus cereus</i> and Dynamic Changes in Their Germinosomes and SpoVAEa during Germination

Bacillus cereus spores, like most Bacillus spores, can survive for years and germinate when their surroundings become suitable, and germination proteins play an important role in the initiation of germination. Because germinated spores lose the extreme resistance of dormant spores, information on the function of germination proteins could be useful in developing new strategies to control B. cereus spores. Prior work has shown that (i) the channel protein SpoVAEa exhibits high-frequency movement in the outer leaflet of the inner membrane (IM) in dormant B. subtilis spores and (ii) the formation of the foci termed germinosomes between two germination proteins, the germinant receptor GerR and the scaffold protein GerD, in developing B. cereus spores is slower than foci formation by GerR and GerD individually. However, the movement dynamics of SpoVAEa in B. cereus spores, and the behavior of the germinosome upon B. cereus spore germination, are not known. In this study, we found that SpoVAEa fluorescent foci in dormant B. cereus spores move on the IM, but slower than in B. subtilis spores, and they likely co-localize transiently with GerD-mScarlet-I in the germinosome. Our results further indicate that (i) the expression of GerR-SGFP2 and SpoVAEa-SGFP2 with GerD-mScarlet-I from a plasmid leads to more heterogeneity and lower efficiency of spore germination in B. cereus, and (ii) germinosome foci observed by Fluorescence resonance energy transfer (FRET) between GerR-SGFP2 and GerD-mScarlet-I can be lost soon after the spore-phase transition. However, this is not always the case, as some GerR-SGFP2 and GerD-mScarlet-I foci continued to exist, co-localize, and even show a weak FRET signal. These data highlight the heterogeneous behavior of spore germination protein complexes and indicate that some complexes may persist beyond the initiation of germination. IMPORTANCE Bacillus cereus is commonly present in soil and infects humans via contaminated food. In this study, we used B. cereus spores to investigate the movement of the spore-specific inner membrane (IM) channel protein SpoVAEa, the interaction between SpoVAEa and the germinosome scaffold protein GerD, and the dynamics of germinosomes with GerR and GerD in spore germination. Our results expand upon observations of interactions between specific B. cereus spore germination proteins, in particular the GerR germinant receptor A, B, and C subunits and GerD, as well as those between SpoVAEa and GerD. The approaches used in this work could also be used to examine the interactions between GerD and SpoVAEa and other germination proteins in spores of other Bacillus species