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Resummed event-shape variables in DIS

Mrinal Dasgupta·Gavin P. Salam
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Abstract

We complete our study of resummed event-shape distributions in DIS by presenting results for the class of observables that includes the current jet mass, the C-parameter and the thrust with respect to the current-hemisphere thrust axis. We then compare our results to data for all observables for which data exist, fitting for alpha_s and testing the universality of non-perturbative 1/Q effects. A number of technical issues arise, including the extension of the concept of non-globalness to the case of discontinuous globalness; singularities and non-convergence of distributions other than in the Born limit; methods to speed up fixed-order Monte Carlo programs by up to an order of magnitude, relevant when dealing with many x and Q points; and the estimation of uncertainties on the predictions.

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Mrinal Dasgupta, Gavin P. Salam. 2002-08-07. Resummed event-shape variables in DIS. https://doi.org/10.1088/1126-6708%2F2002%2F08%2F032

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