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DOE OSTI · 2406100

Power counting to saturation

Stewart, Iain W.·Vaidya, Varun
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Abstract

We present a description of saturation in small 𝑥 deep inelastic scattering from power counting in a top-down effective theory derived from quantum chromodynamics (QCD). A factorization formula isolates the universal physics of the nucleus at leading power in 𝑥. The onset of saturation is then understood as a breakdown in the expansion in an emergent power counting parameter, which is defined by the matrix element of a gauge invariant operator. We identify a new radiation mode, which enables us to extend previous literature by distinguishing the appearance of the saturation scale from the transition to nonlinear evolution.

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Stewart, Iain W., Vaidya, Varun. 2024-07-23. Power counting to saturation. https://doi.org/10.1103/physrevd.110.l011504

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