Hadronic Diffraction: Where Do We Stand? *
نویسنده
چکیده
Experimental results on hadronic soft and hard diffractive processes are reviewed with emphasis on aspects of the data that point to the underlying QCD mechanism for diffraction. Diffractive differential cross sections are shown to be factorized into two terms, one representing the total cross section at the reduced energy, corresponding to the rapidity region(s) in which there is particle production, and another interpreted as the probability of formation of the rapidity gap(s) characterizing diffraction. By (re)normalizing the term of gap formation probability to unity, cross sections for single, central, and multiple rapidity gap soft diffraction, as well as structure functions for hard diffraction processes, are obtained from the underlying inclusive parton distribution functions. A unified partonic picture emerges, in which diffraction appears to be mediated by the exchange of low-x partons subject to color constraints. To appear in: Proc. Les Rencontres de Physique de la Vallé d’Aoste, La Thuile, Aosta Valley, Italy, February 29 March 6, 2004.
منابع مشابه
Adhesive small bowel obstruction: where do we stand now?
Adhesive small bowel obstruction (ASBO) is one of the most frequently encountered disorders in Emergency Surgery Departments worldwide without negligible hospital admission rates and social costs (1,2). Notwithstanding significant improvements in techniques and materials, intra-abdominal adhesions following abdominal surgery still represent a major unsolved and debated issue harbouring challeng...
متن کاملThe Hadronic Light-by-Light Contribution to the Muon Anomalous Magnetic Moment: Where Do We Stand?
We review the status of the hadronic light-by-light contribution to the muon anomalous magnetic moment and critically compare recent calculations. We also study in detail which momentum regions the π 0 exchange main contribution originates. We also argue that a light−by−light µ
متن کاملEvidence - based CAM: Where does it stand?
In the past 10 years evidence - based medicine (EBM) has developed well in all aspects of allopathic medicine giving a new dimension to patient care including cost reduction and attention to medical ethics. With the public and medical community return to complementary and alternative medicine (CAM) in the last two decades there has been a call for evidence - based CAM … in the same way that all...
متن کاملMULTIHADRON PRODUCTION FOR e e FOR FROM 50 TO 61 GeV, C. M. ENERGIES AND COMPARISON WITH MULTIHADRON PRODUCTION IN HADRONIC INTERACTIONS
Average values of< 1- T >where T is the thrust are presented for e: e: AMY data and are compared with their values in hadronic interactions. As far as possible, similar analysis techniques have been employed in the two different interactions. Similar variation with E is observed for this average in both data. The values of < PT> and < PL > relative to the thrust axis in e e are simila...
متن کامل