Perturbative Odderon in the Dipole Model

Abstract

We show that, in the framework of Mueller's dipole model, the perturbative QCD odderon is described by the dipole model equivalent of the BFKL equation with a $C$-odd initial condition. The eigenfunctions and eigenvalues of the odderon solution are the same as for the dipole BFKL equation and are given by the functions $E^{n,\nu }$ and $\chi (n,\nu )$ correspondingly, where the $C$-odd initial condition allows only for odd values of $n$. The leading high-energy odderon intercept is given by ${\alpha }_{odd}-1=\frac{2\text{as}{N}_c}{\pi }\chi (n=1,\nu =0)=0$ in agreement with the solution found by Bartels, Lipatov and Vacca. We proceed by writing down an evolution equation for the odderon including the effects of parton saturation. We argue that saturation makes the odderon solution a decreasing function of energy.

Comments: 1+16 pages, 6 figures, v2: more calculational details added