On the massless contributions to the vacuum polarization of heavy quarks
نویسندگان
چکیده
منابع مشابه
On the massless contributions to the vacuum polarization of heavy quarks
In Ref. [1] Groote and Pivovarov have given notice of a possible fault in the use of sum rules involving two–point correlation functions to extract information on heavy quark parameters, due to the presence of massless contributions that invalidate the construction of moments of the spectral densities. Here we show how to circumvent this problem through a new definition of the moments, providin...
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ژورنال
عنوان ژورنال: Journal of Physics G: Nuclear and Particle Physics
سال: 2003
ISSN: 0954-3899
DOI: 10.1088/0954-3899/29/2/311