DEFINITION AND EVOLUTION OF TRANSVERSE MOMENTUM DISTRIBUTIONS
2012 ◽
Vol 20
◽
pp. 92-108
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Keyword(s):
We consider the definition of unpolarized transverse-momentum-dependent parton distribution functions while staying on-the-light-cone. By imposing a requirement of identical treatment of two collinear sectors, our approach, compatible with a generic factorization theorem with the soft function included, is valid for all non-ultra-violet regulators (as it should), an issue which causes much confusion in the whole field. We explain how large logarithms can be resummed in a way which can be considered as an alternative to the use of Collins-Soper evolution equation. The evolution properties are also discussed and the gauge-invariance, in both classes of gauges, regular and singular, is emphasized.
2014 ◽
Vol 25
◽
pp. 1460016
2015 ◽
Vol 37
◽
pp. 1560022
2008 ◽
Vol 802
(1-2)
◽
pp. 146-179
◽
2009 ◽
Vol 24
(35n37)
◽
pp. 2913-2923
◽
2017 ◽
Vol 32
(19n20)
◽
pp. 1750121
◽
2013 ◽
Vol 726
(4-5)
◽
pp. 795-801
◽
2010 ◽
Vol 840
(1-2)
◽
pp. 379-404
◽