“…This approach has been shown not only to describe a wide range of HERA data, but also the double diffractive dijet production data from the CDF Collaboration [13,18], if a 'gap survival factor' is included to account for the fact that multi-parton interactions in proton-antiproton collisions will reduce the observed rate of double pomeron collisions. This factor can be extracted from data, by scaling the absolute predictions derived using the H1 diffractive structure functions [19], or calculated using phenomenological approaches of varying degrees of sophistication, but in general based on eikonal methods and total cross section measurements [20,21,22,23,24,25]. It is the latter calculational approach that Khoze et al use to estimate the gap survival probability in their central exclusive predictions.…”