20,387 research outputs found
Jet substructure and probes of CP violation in Vh production
We analyse the hVV (V = W, Z) vertex in a model independent way using Vh
production. To that end, we consider possible corrections to the Standard Model
Higgs Lagrangian, in the form of higher dimensional operators which parametrise
the effects of new physics. In our analysis, we pay special attention to linear
observables that can be used to probe CP violation in the same. By considering
the associated production of a Higgs boson with a vector boson (W or Z), we use
jet substructure methods to define angular observables which are sensitive to
new physics effects, including an asymmetry which is linearly sensitive to the
presence of CP odd effects. We demonstrate how to use these observables to
place bounds on the presence of higher dimensional operators, and quantify
these statements using a log likelihood analysis. Our approach allows one to
probe separately the hZZ and hWW vertices, involving arbitrary combinations of
BSM operators, at the Large Hadron Collider.Comment: 37 pages, 17 figures; v3 matches published versio
User oriented access to secure biomedical resources through the grid
The life science domain is typified by heterogeneous data sets that are evolving at an exponential rate. Numerous post-genomic databases and areas of post-genomic life science research have been established and are being actively explored. Whilst many of these databases are public and freely accessible, it is often the case that researchers have data that is not so freely available and access to this data needs to be strictly controlled when distributed collaborative research is undertaken. Grid technologies provide one mechanism by which access to and integration of federated data sets is possible. Combining such data access and integration technologies with fine grained security infrastructures facilitates the establishment of virtual organisations (VO). However experience has shown that the general research (non-Grid) community are not comfortable with the Grid and its associated security models based upon public key infrastructures (PKIs). The Internet2 Shibboleth technology helps to overcome this through users only having to log in to their home site to gain access to resources across a VO – or in Shibboleth terminology a federation. In this paper we outline how we have applied the combination of Grid technologies, advanced security infrastructures and the Internet2 Shibboleth technology in several biomedical projects to provide a user-oriented model for secure access to and usage of Grid resources. We believe that this model may well become the de facto mechanism for undertaking e-Research on the Grid across numerous domains including the life sciences
Mutual Trust and Cooperation in the Evolutionary Hawks-Doves Game
Using a new dynamical network model of society in which pairwise interactions
are weighted according to mutual satisfaction, we show that cooperation is the
norm in the Hawks-Doves game when individuals are allowed to break ties with
undesirable neighbors and to make new acquaintances in their extended
neighborhood. Moreover, cooperation is robust with respect to rather strong
strategy perturbations. We also discuss the empirical structure of the emerging
networks, and the reasons that allow cooperators to thrive in the population.
Given the metaphorical importance of this game for social interaction, this is
an encouraging positive result as standard theory for large mixing populations
prescribes that a certain fraction of defectors must always exist at
equilibrium.Comment: 23 pages 12 images, to appea
TCG based approach for secure management of virtualized platforms: state-of-the-art
There is a strong trend shift in the favor of adopting virtualization to get business benefits. The provisioning of virtualized enterprise resources is one kind of many possible scenarios. Where virtualization promises clear advantages it also poses new security challenges which need to be addressed to gain stakeholders confidence in the dynamics of new environment. One important facet of these challenges is establishing 'Trust' which is a basic primitive for any viable business model. The Trusted computing group (TCG) offers technologies and mechanisms required to establish this trust in the target platforms. Moreover, TCG technologies enable protecting of sensitive data in rest and transit. This report explores the applicability of relevant TCG concepts to virtualize enterprise resources securely for provisioning, establish trust in the target platforms and securely manage these virtualized Trusted Platforms
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