Speaker
Prof.
Yuri Kovchegov
(The Ohio State University)
Description
We derive and solve small-x evolution equations determining the small-x asymptotics of quark and gluon helicity PDFs and TMDs and orbital angular momentum (OAM) distributions. Our evolution equations resum powers of $\alpha_s \ln^2 (1/x)$. At large $N_c$, solving our equations, we obtain the following small-x asymptotics for helicity PDFs and OAM:
$\Delta \Sigma (x, Q^2) = - L_{q + \bar{q}} (x, Q^2) \sim
\left(\frac{1}{x}\right)^{\frac{4}{\sqrt{3}} \, \sqrt{\frac{\alpha_s
\, N_c}{2 \pi}} }$ ,
$\Delta G (x, Q^2) \sim L_G (x, Q^2) \sim
\left(\frac{1}{x}\right)^{\frac{13}{4 \sqrt{3}} \, \sqrt{\frac{\alpha_s
\, N_c}{2 \pi}}}$.
Author
Prof.
Yuri Kovchegov
(The Ohio State University)
