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Zation conjecture has by now received most acceptance, despite the fact that not yet becoming completely established. four.five.1 Summary of recent experimental progress The previous couple of years have observed incredible progress in measurements of quarkonium production observables, which was mostly, but not solely, due to the operation of the different LHC experiments. Here we'll give an overview on the most remarkable results from the previous years. The production rates of a heavy quarkonium H are split into direct, prompt, and nonprompt contributions. Direct production refers for the production of H directly in the interaction point of your initial particles, whilst prompt production also contains production by way of radiative decays of larger quarkonium states, named CUDC-907 web feed-down contributions. Nonprompt production refers to all other production mechanisms, mostly the production of charmonia from decaying B mesons, which is often identified by a second decay vertex displaced in the interaction point. a. J/ production in pp collisions The 2004 CDF transverse momentum pT distribution measurement on the J/ production cross section [1141] is still amongst the most precise heavy quarkonium production measurements. But due to the fact theory errors in all models for heavy quarkonium production are nonetheless substantially bigger than today's experimental errors, it is actually normally not higher precision which can be needed from the theory side, but rather new and much more title= fpsyg.2017.00209 diverse production observables. And this can be where the LHC experiments have offered crucial input. As for the J/ hadroproduction cross section, they have extended the CDF measurement [1141] into new kinematic regions: Clearly, the measurements have already been performed at a great deal greater center-of-mass energies than prior to, namely at s = two.76, 7, and 8 TeV. But far more significant for testing quarkonium production models may be the truth that you can find measurements which exceed the previously measured pT variety both at higher pT , as by ATLAS [1142] and CMS [1143], and at low pT , as inside the earlier CMS measurement [1144], but in addition in the recent measurement by the PHENIX collaboration at RHIC [1145]. We note that this list just isn't comprehensive, and that there happen to be several a lot more J/ hadroproduction measurements lately than these cited right here. b. (2S) and c production in pp collisions J/ may be the quarkonium that is easiest to become measured resulting from thelarge branching ratio of its leptonic decay modes, but in current years, high precision measurements happen to be also performed for the (2S), namely by the CDF [1146], the CMS [1143], plus the LHCb [1147] collaborations. Also the c production cross sections were measured through their decays into J/ by LHCb [1148], the very first time since the CDF measurement [1149] in 2001. The c2 to c1 production ratio was measured at LHCb [1150], CMS [1151] and previously by title= 17470919.2015.1029593 CDF [1152]. These measurements are of terrific importance for the theory side since they allow fits of NRQCD LDMEs for these charmonia and figure out direct J/ production information, which can in turn be when compared with direct production theory predictions. c. production in pp collisions (1S), (2S), and (3S) production cross sections have been measured at the LHC by ATLAS [1153] and LHCb [1154,1155].

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