منابع مشابه
Hadronic B decays from SCET
The standard model (SM) of particle physics has proven to hold up against any experimental tests it has been subjected to so far. The SM has several striking features for which no underlying principle has been experimentally confirmed to this date. First, the SM requires the scale of electro-weak symmetry breaking to be of order a few hundred GeV, which is many orders of magnitude below the onl...
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We discuss the kinematics of the particles that make up a Reggeon in field theory, using the terminology of the soft collinear effective theory (SCET). Reggeization sums a series of strongly ordered collinear emissions resulting in an overall Reggeon exchange that falls in the Glauber or Coulomb kinematic region. This is an extremely multiscale problem and appears to fall outside of the usual o...
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We show, for previously uncalculated examples containing a uniform mass in the loop, that it is possible to obtain complete massive one-loop gauge theory amplitudes solely from unitarity and known ultraviolet or infrared mass singularities. In particular, we calculate four-gluon scattering via massive quark loops in QCD. The contribution of a heavy quark to five-gluon scattering with identical ...
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We identify a hidden GL(n,C) symmetry of the tree level n-point MHV gravity amplitude. Representations of this symmetry reside in an auxiliary n-space whose indices are external particle labels. Spinor helicity variables transform non-linearly under GL(n,C), but linearly under its notable subgroups, the little group and the permutation group Sn. Using GL(n,C) covariant variables, we present a n...
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ژورنال
عنوان ژورنال: Physics Letters B
سال: 2004
ISSN: 0370-2693
DOI: 10.1016/j.physletb.2004.10.047