Light and compressed gluinos at the LHC via string theory

In this article, we show that making global fits of string theory model parameters to data is an interesting mechanism for probing, mapping and forecasting connections of the theory to real world physics. We considered a large volume scenario (LVS) with D3-branes matter fields and supersymmetry breaking. A global fit of the parameters to low energy data shows that the set of LVS models are associated with light gluinos which are quasi-degenerate with the neutralinos and charginos they can promptly decay into and thus possibly hidden to current LHC gluino search strategies.Comment: v2: minor edits, additional references, accepted for publication in the European Physical Journal

Soft SUSY Breaking Terms for Chiral Matter in IIB String Compactifications

This paper develops the computation of soft supersymmetry breaking terms for chiral D7 matter fields in IIB Calabi-Yau flux compactifications with stabilised moduli. We determine explicit expressions for soft terms for the single-modulus KKLT scenario and the multiple-moduli large volume scenario. In particular we use the chiral matter metrics for Calabi-Yau backgrounds recently computed in hep-th/0609180. These differ from the better understood metrics for non-chiral matter and therefore give a different structure of soft terms. The soft terms take a simple form depending explicitly on the modular weights of the corresponding matter fields. For the large-volume case we find that in the simplest D7 brane configuration, scalar masses, gaugino masses and A-terms are very similar to the dilaton-dominated scenario. Although all soft masses are suppressed by ln(M_P/m_{3/2}) compared to the gravitino mass, the anomaly-mediated contributions do not compete, being doubly suppressed and thus subdominant to the gravity-mediated tree-level terms. Soft terms are flavour-universal to leading order in an expansion in inverse Kahler moduli. They also do not introduce extra CP violating phases to the effective action. We argue that soft term flavour universality should be a property of the large-volume compactifications, and more generally IIB flux models, in which flavour is determined by the complex structure moduli while supersymmetry is broken by the Kahler moduli. For the simplest large-volume case we run the soft terms to low energies and present some sample spectra and a basic phenomenological analysis.Comment: 40 pages, 9 figures, JHEP style; v2. sentence rephrase

Logistics education at historically black colleges and universities

A review of research literature on logistics education reveals disparities between demand for and supply of logistics management skills. Racial minorities are relatively underrepresented in logistics education and professional careers. In order to meet the rising demand for college graduates and mitigate racial disparities in the field, a need arises to enhance logistics education at Historically Black Colleges and Universities (HBCU’s). HBCU’s are known to have a high rate of success in retaining and graduating African American students. Yet, only a few of these institutions offer logistics degree programs or concentrations within the business and social science majors. This article makes a case for enhancing logistics education at HBCU’s through program development, recruitment, and retention strategies. It argues that the coordination of activities and partnerships between the institutions offering the programs, high schools/community colleges, and employers of the graduates and government are essential for the success of such strategies

On The Existence of A Unique Solution for Systems of Ordinary Differential Equations of First Order

In this paper, we state and prove a theorem for local existence of a unique solution for a system of nonlinear ordinary differential equations ( NODE ) of first order by proving that the nonlinear operator of this system is contractive in a metric space subset of the Banach space consisting of the bounded differentiable functions on the real numbers and equipped with a Bielescki#39s type norm.nbsp Finally, we give examples to illustrate our result