Correlations in double parton distributions at small x

• Published in: The journal of high energy physics Vol. 2011; no. 6; p. 1
• Main Authors: Flensburg, Christoffer, Gustafson, Gösta, Lönnblad, Leif, Ster, Andras
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.06.2011; Springer Nature B.V
• Subjects: Classical and Quantum Gravitation; Dependence; Dipoles; Elastic scattering; Elementary Particles; Fysik; High energy physics; Jets; Natural Sciences; Naturvetenskap; Parton Model; Partons; Phenomenological Models; Physical Sciences; Physics; Physics and Astronomy; QCD; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Relativity Theory; Scattering cross sections; String Theory; Subatomic Physics; Subatomär fysik; Phenomenological Models; QCD Phenomenology
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP06(2011)066

We present a dynamical study of the double parton distribution in impact parameter space, which enters into the double scattering cross section in hadronic collisions. This distribution is analogous to the generalized parton densities in momentum space. We use the Lund Dipole Cascade model, presented in earlier articles, which is based on BFKL evolution including essential higher order corrections and saturation effects. As result we find large correlation effects, which break the factorization of the double scattering process. At small transverse separation we see the development of “hot spots”, which become stronger with increasing Q 2 . At smaller x -values the distribution widens, consistent with the shrinking of the diffractive peak in elastic scattering. The dependence on Q 2 is, however, significantly stronger than the dependence on x , which has implications for extrapolations to LHC, e.g. for results for underlying events associated with the production of new heavy particles.