Signatures of Supersymmetry in B Decays - A Theoretical Perspective

We discuss precision tests of the standard model in radiative and semileptonic rare B-decays and CP-violating asymmetries, and possible signatures of supersymmetry in these processes. Motivated by current data, and with an eye on the forthcoming measurements, we restrict ourselves to the processes in which the bench marks set by the standard model have either been met by ongoing experiments or are expected to be met shortly. This includes the mixing-induced CP asymmetry, measured through $\sin 2 \beta$, and branching ratios for the radiative and semileptonic rare decays $B \to X_s \gamma$, $B \to K^* \gamma$, $B \to X_s \ell^+ \ell^-$ and $B \to (K,K^*) \ell^+ \ell^-$, where $\ell^\pm =e^\pm, \mu^\pm$.Comment: 19 pages, 5 figures (requires sprocl.sty and epsf); invited talk, to be published in the proceedings of the International Conference on Flavor Physics ICFP2001, Zhang-Jia-Jie City, Peoples Republic of China, May 31 - June 6, 200

Inequality and the Dynamics of Poverty and Growth

This paper models the dynamic interactions between growth and distribution in the analysis of the behavior of poverty over time. The model permits formal analysis of the factors that led to the growth collapse as well as the rise in poverty in Africa and other developing regions, except Asia, during 1975-96 period. Using indicators of average country performance during this period-- in terms of the rate of acceleration of growth, changes in poverty and extent of inequality—the model suggests tentative strategies for dealing with poverty. The main policy recommendation of this analysis is that, for the majority of countries—36 out of 47—any serious strategy for poverty reduction must include both policies for accelerating growth as well as measures for effecting more equitable income distribution. Moreover, the latter must be sufficiently deep either to shake-off the "transitional", though lingering, "low equilibrium trap" that characterizes some economies; or to more others from the "bad" equilibrium of stationary, but high, poverty.

Improved η′\eta^\prime-Meson Distribution Amplitudes from Inclusive Υ(1S)→η′X\Upsilon (1S) \to \eta^\prime X Decay

We calculate the $\eta^\prime$-meson energy spectrum in the $\Upsilon (1S) \to \eta^\prime g g g \to \eta^\prime X$ decay in the leading-order perturbative QCD in the static-quark limit for the orthoquarkonium.Our principal result is the extraction of parameters of the $\eta^\prime g^* g$ effective vertex function (EVF) involving a virtual and a real gluon from the available data on the hard part of the $\eta^\prime$-meson energy spectrum. The perturbative-QCD based framework provides a good description of the available CLEO data, allowing one to constrain the lowest Gegenbauer coefficients $B^{(q)}_2$ and $B^{(g)}_2$ of the quark-antiquark and gluonic distribution amplitudes of the $\eta^\prime$-meson. The resulting constraints are combined with the existing ones on these coefficients from an analysis of the $\eta^\prime - \gamma$ transition form factor and the requirement of positivity of the EVF, yielding $B^{(q)}_2 (\mu_0^2) = -0.008 \pm 0.054$ and $B^{(g)}_2 (\mu_0^2) = 4.6 \pm 2.5$ for $\mu_0^2 = 2 GeV^2$. This reduces significantly the current uncertainty on these coefficients.Comment: 4 pages, 4 figures, use svjour.cls and svepj.clo; talk given at the International Europhysics Conference on High-Energy Physics (HEP 2003), 17-23 July 2003, Aachen, Germany. Title change

Branching Ratios for B→K∗γB \to K^* \gamma and B→ργB \to \rho \gamma Decays in Next-to-Leading Order in the Large Eneregy Effective Theory

We calculate the so-called hard spectator corrections in ${\cal O} (\alpha_s)$ in the leading-twist approximation to the decay widths for $B \to K^{*} \gamma$ and $B \to \rho \gamma$ decays and their charge conjugates, using the Large Energy Effective Theory (LEET) techniques. Combined with the hard vertex and annihilation contributions, they are used to compute the branching ratios for these decays in the next-to-leading order (NLO) in the strong coupling $\alpha_s$ and in leading power in $\Lambda_{\rm QCD}/M_B$. These corrections are found to be large, leading to the inference that the theoretical branching ratios for the decays $B \to K^* \gamma$ in the LEET approach can be reconciled with current data only for significantly lower values of the form factors than their estimates in the QCD sum rule and Lattice QCD approaches. However, the form factor related uncertainties mostly cancel in the ratios ${\cal B}(B \to \rho \gamma)/{\cal B}(B \to K^* \gamma)$ and $\Delta = (\Delta^{+0}+ \Delta^{-0})/2$, where $\Delta^{\pm 0} = \Gamma (B^\pm \to \rho^\pm \gamma)/ [2 \Gamma (B^0 (\bar B^0)\to \rho^0 \gamma)] - 1$, and hence their measurements will provide quantitative information on the standard model parameters, in particular the ratio of the CKM matrix elements $| V_{td}/V_{ts}|$ and the inner angle $\alpha$ of the CKM-unitarity triangle. We also calculate direct CP asymmetries for the decays $B^\pm \to \rho^\pm \gamma$ and $B^0/\bar B^0 \to \rho^0 \gamma$ and find, in conformity with the observations made in the existing literature, that the hard spectator contributions significantly reduce the asymmetries arising from the vertex corrections.Comment: 45 pages, 18 figures (requires amssymb and epsf); replaced with the revised versio

Insolvency – Temporary management of an insolvent bank

In this paper the author analyses the arguments put forward by parties in the case of Century National Merchant Bank v Davies before the Judicial Committee of the Privy Council pursuant to an appeal from the Court of Appeal of Jamaica [1998] 2 WLR 779 (PC). Article published in Amicus Curiae - Journal of the Institute of Advanced Legal Studies and its Society for Advanced Legal Studies. The Journal is produced by the Society for Advanced Legal Studies at the Institute of Advanced Legal Studies, University of London