Nine-propagator master integrals for massless three-loop form factors
نویسندگان
چکیده
منابع مشابه
Nine-Propagator Master Integrals for Massless Three-Loop Form Factors
We complete the calculation of master integrals for massless three-loop form factors by computing the previously-unknown three diagrams with nine propagators in dimensional regularisation. Each of the integrals yields a six-fold Mellin-Barnes representation which we use to compute the coefficients of the Laurent expansion in ǫ. Using Riemann ζ functions of up to weight six, we give fully analyt...
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The three-loop form factors in massless QCD can be expressed as a linear combination of master integrals. Besides a number of master integrals which factorise into products of one-loop and two-loop integrals, one finds 16 genuine three-loop integrals. Of these, six have the form of a bubble insertion inside a one-loop or two-loop vertex integral. We compute all master integrals with these inser...
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In this letter we continue the calculation of master integrals for massless three-loop form factors by giving analytical results for those integrals which are relevant for the fermionic contributions proportional toN F , NF ·N , andNF /N . Working in dimensional regularisation, we express one of the integrals in a closed form which is exact to all orders in ǫ, containing Γ-functions and hyperge...
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ژورنال
عنوان ژورنال: Physics Letters B
سال: 2009
ISSN: 0370-2693
DOI: 10.1016/j.physletb.2009.06.038