Mine Environmental Control

IMR Report on mine ventilation

Researching trust in the police and trust in justice: a UK perspective

This paper describes the immediate and more distant origins of a programme of comparative research that is examining cross-national variations in public trust in justice and in the police. The programme is built around a module of the fifth European Social Survey, and evolved from a study funded by the European Commission. The paper describes the conceptual framework within which we are operating – developed in large measure from theories of procedural justice. It reviews some of the methodological issues raised by the use of sample surveys to research issues of public trust in the police, public perceptions of institutional legitimacy and compliance with the law. Finally it gives a flavour of some of the early findings emerging from the programme

Unitary representations of the Galilean line group: Quantum mechanical principle of equivalence

We present a formalism of Galilean quantum mechanics in non-inertial reference frames and discuss its implications for the equivalence principle. This extension of quantum mechanics rests on the Galilean line group, the semidirect product of the real line and the group of analytic functions from the real line to the Euclidean group in three dimensions. This group provides transformations between all inertial and non-inertial reference frames and contains the Galilei group as a subgroup. We construct a certain class of unitary representations of the Galilean line group and show that these representations determine the structure of quantum mechanics in non-inertial reference frames. Our representations of the Galilean line group contain the usual unitary projective representations of the Galilei group, but have a more intricate cocycle structure. The transformation formula for the Hamiltonian under the Galilean line group shows that in a non-inertial reference frame it acquires a fictitious potential energy term that is proportional to the inertial mass, suggesting the equivalence of inertial mass and gravitational mass in quantum mechanics

Valence-quark distributions in the pion

We calculate the pion's valence-quark momentum-fraction probability distribution using a Dyson-Schwinger equation model. Valence-quarks with an active mass of 0.30 GeV carry 71% of the pion's momentum at a resolving scale q_0=0.54 GeV = 1/(0.37 fm). The shape of the calculated distribution is characteristic of a strongly bound system and, evolved from q_0 to q=2 GeV, it yields first, second and third moments in agreement with lattice and phenomenological estimates, and valence-quarks carrying 49% of the pion's momentum. However, pointwise there is a discrepancy between our calculated distribution and that hitherto inferred from parametrisations of extant pion-nucleon Drell-Yan data.Comment: 8 pages, 3 figures, REVTEX, aps.sty, epsfig.sty, minor corrections, version to appear in PR

Depositional environment and apparent age of the Fauske carbonate conglomerate, North Norwegian Caledonides

The Fauske conglomerate represents a rather rare case of a monomict carbonate conglomerate in the Late Neoproterozoic to Silurian, lithostratigraphic successionsof the Norwegian Caledonides. Lithological varieties of this conglomerate unit from the Lovgavlen quarry have a highly decorative quality and are well known in both domestic and international markets under trading names such as 'Norwegian Rose', 'Jaune Rose', 'Norwegian Green', 'Antique Fonce' and 'Hermelin'. The Fauske conglomerate is a 60m-thick unit which rests on either dark grey ('blue') calcite marbles or white dolomite marbles. The latter are jointed and fragmented, and also appear as sedimentary collapse-breccia and debris where they are in direct contact with the conglomerate. Although the Fauske conglomerate has been involved in two main pulses of Caledonian tectonic deformation, which produced an early, syn-metamorphic flattening of the clasts and a later folding or rotation of clasts into a spaced cleavage, the overall sedimentary features are still remarkably well preserved. The Fauske conglomerate unit consists of 25 beds (5 cm to 3 metres thick) comprising landslide, carbonate debris and carbonate breccia-conglomero-breccias-greywacke lithofacies. Blocks, fragments, cobbles, pebbles and smaller clasts are mainly of white dolostone and pink, beige, white and 'blue' calcite marbles. The matrix has a granoblastic texture and similar range in lithology with variable amounts of quartz, fuchsite, sericite, muscovite and chlorite. Within the unit, an upward fining of the clasts is followed by the gradual development of calcareous greywacke layers which show both cross bedding and channelling. The depositional model involves: (i) a locally developed, tectonically unstable carbonate shelf-margin, (ii) a temporary lowering o sea level, (iii) formation of a high-relief, shore-to-basin fault scarp followed by (iv) the development of a channel, with (v) subsequent, long-distance transport of clasts of pink carbonates from the continent-basin margin,w hich were (vi) redeposited together with a carbonate debris (white dolomite and 'blue' calcite marbles) on the tectonically fragmenting edge of a carbonate shelf. Both matrix and pebbles show a similar range in isotopic values: -1.9 to +0.6 per mil (vs. PDB) for 13Ccarb and 0.70896 to 0.70946 for 87Sr/86Sr. The least altered 87Sr/86Sr (0.70896) isotopic value plotted on the calibration curve is consistent with a seawater composition corresponding to ages of 470-475, 505-510 and 520, whereas the least altered 13C carb (-0.6 per mil) value matches only 520 Ma

Optogalvanic Spectroscopy of Metastable States in Yb^{+}

The metastable ^{2}F_{7/2} and ^{2}D_{3/2} states of Yb^{+} are of interest for applications in metrology and quantum information and also act as dark states in laser cooling. These metastable states are commonly repumped to the ground state via the 638.6 nm ^{2}F_{7/2} -- ^{1}D[5/2]_{5/2} and 935.2 nm ^{2}D_{3/2} -- ^{3}D[3/2]_{1/2} transitions. We have performed optogalvanic spectroscopy of these transitions in Yb^{+} ions generated in a discharge. We measure the pressure broadening coefficient for the 638.6 nm transition to be 70 \pm 10 MHz mbar^{-1}. We place an upper bound of 375 MHz/nucleon on the 638.6 nm isotope splitting and show that our observations are consistent with theory for the hyperfine splitting. Our measurements of the 935.2 nm transition extend those made by Sugiyama et al, showing well-resolved isotope and hyperfine splitting. We obtain high signal to noise, sufficient for laser stabilisation applications.Comment: 8 pages, 5 figure

No Dynamics in the Extremal Kerr Throat

Motivated by the Kerr/CFT conjecture, we explore solutions of vacuum general relativity whose asymptotic behavior agrees with that of the extremal Kerr throat, sometimes called the Near-Horizon Extreme Kerr (NHEK) geometry. We argue that all such solutions are diffeomorphic to the NHEK geometry itself. The logic proceeds in two steps. We first argue that certain charges must vanish at all times for any solution with NHEK asymptotics. We then analyze these charges in detail for linearized solutions. Though one can choose the relevant charges to vanish at any initial time, these charges are not conserved. As a result, requiring the charges to vanish at all times is a much stronger condition. We argue that all solutions satisfying this condition are diffeomorphic to the NHEK metric.Comment: 42 pages, 3 figures. v3: minor clarifications and correction

Study of KS KL Coupled Decays and KL -Be Interactions with the CMD-2 Detector at VEPP-2M Collider

The integrated luminosity about 4000 inverse nanobarn of around phi meson mass ( 5 millions of phi mesons) has been collected with the CMD-2 detector at the VEPP-2M collider. A latest analysis of the KS KL coupled decays based on 30 % of available data is presented in this paper. The KS KL pairs from phi meson decays were reconstructed in the drift chamber when both kaons decayed into two charged particles. From a sample of 1423 coupled decays a selection of candidates to the CP violating KL into pi+ pi- decay was performed. CP violating decays were not identified because of the domination of events with a KL regenerating at the Be beam pipe into KS and a background from KL semileptonic decays. The regeneration cross section of 110 MeV/c KL mesons was found to be 53 +- 17 mb in agreement with theoretical expectations. The angular distribution of KS mesons after regeneration and the total cross section of KL for Be have been measured.Comment: 14 pages, 8 figure

Three-body non-additive forces between spin-polarized alkali atoms

Three-body non-additive forces in systems of three spin-polarized alkali atoms (Li, Na, K, Rb and Cs) are investigated using high-level ab initio calculations. The non-additive forces are found to be large, especially near the equilateral equilibrium geometries. For Li, they increase the three-atom potential well depth by a factor of 4 and reduce the equilibrium interatomic distance by 0.9 A. The non-additive forces originate principally from chemical bonding arising from sp mixing effects.Comment: 4 pages, 3 figures (in 5 files

Study of the radiative decay ϕ→ηγ\phi \to \eta \gamma with CMD-2 detector

Using the $1.9 pb^{-1}$ of data collected with the CMD-2 detector at VEPP-2M the decay mode $\phi \to \eta \gamma$, $\eta \to \pi^+\pi^-\pi^0$ has been studied. The obtained branching ratio is B($\phi \to \eta \gamma) = (1.18 \pm 0.03 \pm 0.06)$.Comment: 13 pages, 5 figures, LaTex2e, to be published in Phys. Lett.