for example, Refs. [@Bj]–[@a17]). They correspond to the diagrams of Fig. \[fig:2\], and can be calculated using the Reggeon diagram technique [@a10].

![Unitarity or rescattering corrections to the exclusive diffractive process $pp\to p + h + p$. \[fig:2\]](fig2.eps){height="5cm"}

It will be shown in Section \[sec:4\] that the inclusion of these diagrams leads not only to a decrease of the cross sections of the double-Pomeron processes, but also to significant modifications of the angular correlations between the outgoing (forward) protons. Moreover, the magnitude of these absorptive corrections depends on the quantum numbers of the produced state $h$.

In Section \[sec:4\] we illustrate the results using the important topical example of the double-Pomeron production of heavy bosons. In particular we compare the production of a Standard Model Higgs boson with spin-parity $J^P=0^+$, with that for a $0^-$ Higgs[^1] which appears in various extensions of the Standard Model, in particular in a supersymmetric extension. In Section \[sec:5\], we consider the consequences of this approach to investigations of the Higgs sector at the LHC. For illustration we evaluate the exclusive cross sections using the minimal supersymmetric model[^2] (MSSM) with large $\tan\beta$; a domain in which, for $m(0^-)\lesim 200~\GeV$, the conventional searches at the LHC 