HBT Shape Analysis with q-Cumulants
نویسندگان
چکیده
Taking up and extending earlier suggestions, we show how twoand three-dimensional shapes of secondorder HBT correlations can be described in a multivariate Edgeworth expansion around Gaussian ellipsoids, with expansion coefficients, identified as the cumulants of pair momentum difference q, acting as shape parameters. Off-diagonal terms dominate both the character and magnitude of shapes. Cumulants can be measured directly and so the shape analysis has no need for fitting.
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