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Grassmannians and form factors with $q^2=0$ in N=4 SYM theory

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 نشر من قبل Leonid Bork Dr
 تاريخ النشر 2016
  مجال البحث
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We consider tree level form factors of operators from stress tensor operator supermultiplet with light-like operator momentum $q^2=0$. We present a conjecture for the Grassmannian integral representation both for these tree level form factors as well as for leading singularities of their loop counterparts. The presented conjecture was successfully checked by reproducing several known answers in $mbox{MHV}$ and $mbox{N}^{k-2}mbox{MHV}$, $kgeq3$ sectors together with appropriate soft limits. We also discuss the cancellation of spurious poles and relations between different BCFW representations for such form factors on simple examples.



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