Factorization breaking in diffractive dijet production

Abstract

We study diffractive hard dijet production, with one or two rapidity gaps, at high energies. We emphasize that both hard and Regge factorization are broken in these processes. We show that a multi-Pomeron-exchange model for screening effects gives a specific pattern for the breakdown of factorization, which is in good agreement with diffractive dijet data collected at the Tevatron.Comment: 6 pages, 1 figur

Summary of the “Diffraction & Vector Mesons” working group at DIS05

“…The screening corrections are accounted for by the introduction of a suppression factor, which is often called the survival probability of rapidity gaps. As shown in [19] and [20], the current CDF diffractive dijet data, with one or two rapidity gaps, are in good quantitative agreement with the multi-Pomeronexchange model.…”

“…A strong breakdown of factorization at the TEVATRON has been known for some time from run-I (1992-1995) results [28]: the single-diffractive to nondiffractive ratios for dijets, W , b-quark and J/ψ production, as well as the ratio of double-diffractive to non-diffractive dijet production are all ∼ 1%, a factor 10 less than at HERA. However, the ratio of double-to single-diffractive dijets is found to be about a factor 5 larger than the ratio of single-to non-diffractive dijets, suggesting that there is only a small extra suppression when going from one to two rapidity gaps in the event, as confirmed by predictions [20]. In this respect the TEVATRON data are being a very powerful tool to shed light on the factorization breaking mechanism.…”

Diffractive dijet production with a leading proton in ep collisions at HERA

“…This "factorisation breaking" may be explained e.g. by soft interactions or multi-pomeron exchanges between the hadrons and/or rescattering phenomena which destroy the diffractive event signature [14][15][16].…”

DiffractiveZboson pair production at the LHC in the large extra dimensions scenario

“…An estimate of S 2 excl for nuclear collisions was calculated in [21] using the Glauber model. Another conservative estimate can be obtained assuming that [22]: S 2 excl A 1 A 2 = S 2 excl pp /(A 1 · A 2 ) (For a discussion about nuclear diffraction see [23]). In what follows we will consider the latter model for S 2 excl A 1 A 2 when considering the central exclusive Z boson pair production.…”