75,299 research outputs found
Charm semileptonic decays at LHCb
In these proceedings, we explore the possible reach of the LHCb dataset in
the area of charm semileptonic decays. Specifically, we give prospects for the
measurement of using with Run I data.
Preliminary projections show that the LHCb Run I dataset would give a relative
statistical uncertainty of on this ratio. We also motivate the
search for lepton non-universality in the charm sector.Comment: Proceedings of the 9th International Workshop on the CKM Unitarity
Triangle, 28 November - 3 December 2016, Tata Institute for Fundamental
Research (TIFR), Mumbai, India. 6 pages, 3 figure
Cosmic Strings, Zero Modes and SUSY breaking in Nonabelian N=1 Gauge Theories
We investigate the microphysics of cosmic strings in Nonabelian gauge
theories with N=1 supersymmetry. We give the vortex solutions in a specific
example and demonstrate that fermionic superconductivity arises because of the
couplings and interactions dictated by supersymmetry. We then use supersymmetry
transformations to obtain the relevant fermionic zero modes and investigate the
role of soft supersymmetry breaking on the existence and properties of the
superconducting strings.Comment: 12 pages, RevTex, submitted to Phys. Rev.
Configurations of Handles and the Classification of Divergences in the String Partition Function
The divergences that arise in the regularized partition function for closed
bosonic string theory in flat space lead to three types of perturbation series
expansions, distinguished by their genus dependence. This classification of
infinities can be traced to geometrical characteristics of the string
worldsheet. Some categories of divergences may be eliminated in string theories
formulated on compact manifolds.Comment: 24 pages, DAMTP-R/94/1
User's manual for MacPASCO
A user's manual is presented for MacPASCO, which is an interactive, graphic, preprocessor for panel design. MacPASCO creates input for PASCO, an existing computer code for structural analysis and sizing of longitudinally stiffened composite panels. MacPASCO provides a graphical user interface which simplifies the specification of panel geometry and reduces user input errors. The user draws the initial structural geometry and reduces user input errors. The user draws the initial structural geometry on the computer screen, then uses a combination of graphic and text inputs to: refine the structural geometry; specify information required for analysis such as panel load and boundary conditions; and define design variables and constraints for minimum mass optimization. Only the use of MacPASCO is described, since the use of PASCO has been documented elsewhere
Incorporating general race and housing flexibility and deadband in rolling element bearing analysis
Methods for including the effects of general race and housing compliance and outer race-to-housing deadband (clearance) in rolling element bearing mechanics analysis is presented. It is shown that these effects can cause significant changes in bearing stiffness characteristics, which are of major importance in rotordynamic response of turbomachinery and other rotating systems. Preloading analysis is demonstrated with the finite element/contact mechanics hybrid method applied to a 45 mm angular contact ball bearing
Preservation of flavor in freeze dried green beans
Before freeze drying, green beans are heated to point at which their cell structure is altered. Beans freeze dried with altered cell structure have improved rehydration properties and retain color, flavor, and texture
Varying Constants in Brane World Scenarios
Higher-dimensional theories imply that some constants, such as the
gravitational constant and the strength of the gauge-couplings, are not
fundamental constants. Instead they are related to the sizes of the
extra--dimensional space, which are moduli fields in the four--dimensional
effective theory. We study the cosmological evolution of the moduli fields
appearing in brane world scenarios and discuss the implications for varying
constants.Comment: 5 pages, LaTeX, 5 figures; based on a talk given by C. van de Bruck
at JENAM 2002, Porto; typos correcte
Chiral Vortons and Cosmological Constraints on Particle Physics
We investigate the cosmological consequences of particle physics theories
that admit stable loops of current-carrying string - vortons. In particular, we
consider chiral theories where a single fermion zero mode is excited in the
string core, such as those arising in supersymmetric theories with a D-term.
The resulting vortons formed in such theories are expected to be more stable
than their non-chiral cousins. General symmetry breaking schemes are considered
in which strings formed at one symmetry breaking scale become current-carrying
at a subsequent phase transition. The vorton abundance is estimated and
constraints placed on the underlying particle physics theories from
cosmological observations. Our constraints on the chiral theory are
considerably more stringent than the previous estimates for more general
theories.Comment: minor corrections made. This version will appear in PR
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