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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 [https://www.medchemexpress.com/CUDC-907.html 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 [https://dx.doi.org/10.3389/fpsyg.2017.00209 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 [https://dx.doi.org/10.1080/17470919.2015.1029593 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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S) (n = 1, two, 3) transitions with partial widths of 300 - 400 keV [1116]. Recently Belle
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S) (n = 1, two, three) transitions with partial widths of 300 - 400 keV [1116]. Recently Belle reported preliminary outcomes around the observation of (5S) (1S, 2S) and (5S) + - (1D) with anomalously significant prices [985]. It's proposed that these anomalies are because of rescatterings [1123,1124]. The big branching fraction from the (4S) (1S) decay observed in 2010 by BaBar could have a similar origin [1125]. The mechanism can be regarded as either as a rescatter??ing on the D D or B B mesons, or as a [http://www.tongji.org/members/shadow2pantry/activity/516070/ http://www.tongji.org/members/shadow2pantry/activity/516070/] contribution of the molecular component towards the quarkonium wave function. ?The model in which Y (4260) is really a D1 (2420) D molecule naturally explains the high probability of the intermediate molecular resonance within the Y (4260) + - J/ transitions [1126,1127] and predicts the Y (4260) X (3872) transitions with high prices [1128]. Such transitions have not too long ago been observed by BES III, with [1107] K + - (2S)2981 Page 74 ofEur. Phys. J. C (2014) 74:[e+ e- X (3872)] 11 . [e+ e- + - J/](4.15)Regardless of striking similarities in between the observations in the charmonium and bottomonium sectors, you'll find also clear variations. In the charmonium sector, every of the Y (3915), (4040), (4160), Y (4260), Y (4360) and Y (4660) decays to only one certain final state with charmonium [ J/, J/, + - J/ or + - (2S)]. Inside the bottomonium sector, there is certainly a single state with anomalous properties, the (5S), and it decays to distinctive channels with comparable prices [ + - (nS), + - h b (m P), + - (1D), (nS)]. There is no common model describing these peculiarities. To explain the affinity from the charmonium-like states to some particular channels, the notion of "hadrocharmonium" was proposed in [1084]. It really is a heavy quarkonium embedded into a cloud of light hadron(s), therefore the fallapart decay is dominant. Hadrocharmonium could also deliver an explanation for [https://dx.doi.org/10.1089/jir.2014.0001 title= jir.2014.0001] the charged charmonium-like states Z (4430)+ , Z (4050)+ and Z (4250)+ . four.three.five Summary Quarkonium spectroscopy enjoys an intensive flood of new benefits. The number of spin-singlet bottomonium states has elevated from 1 to 4 more than the final 2 years, including a far more precise measurement of your b (1S) mass, 11 MeV away in the PDG2012 typical. There is evidence for one of the two nonetheless missing narrow charmonium states anticipated ??within the area amongst the D D and D D thresholds. Observations and detailed studies from the charged bottomoniumlike states Z b (10610) and Z b (10650) and initial benefits on the charged charmonium-like states Z c open a rich phenomenological field to study exotic states near open flavor thresholds. There's also considerable progress as well as a extra clear experimental scenario for the highly excited heavy quarkonium states above open flavor thresholds. Current highlights incorporate confirmation in the Y (4140) state by CMS and D0, observation of your decays (4040, 4160) J/ by Belle, measurement on the energy dependence with the e+ e- + - h c cross section by BES III, observation of your Y (4260) X (3872) by BES III and determination on the Z (4430) spin arity from complete amplitude analysis by Belle.

Revision as of 06:04, 3 January 2018

S) (n = 1, two, 3) transitions with partial widths of 300 - 400 keV [1116]. Recently Belle S) (n = 1, two, three) transitions with partial widths of 300 - 400 keV [1116]. Recently Belle reported preliminary outcomes around the observation of (5S) (1S, 2S) and (5S) + - (1D) with anomalously significant prices [985]. It's proposed that these anomalies are because of rescatterings [1123,1124]. The big branching fraction from the (4S) (1S) decay observed in 2010 by BaBar could have a similar origin [1125]. The mechanism can be regarded as either as a rescatter??ing on the D D or B B mesons, or as a http://www.tongji.org/members/shadow2pantry/activity/516070/ contribution of the molecular component towards the quarkonium wave function. ?The model in which Y (4260) is really a D1 (2420) D molecule naturally explains the high probability of the intermediate molecular resonance within the Y (4260) + - J/ transitions [1126,1127] and predicts the Y (4260) X (3872) transitions with high prices [1128]. Such transitions have not too long ago been observed by BES III, with [1107] K + - (2S)2981 Page 74 ofEur. Phys. J. C (2014) 74:[e+ e- X (3872)] 11 . [e+ e- + - J/](4.15)Regardless of striking similarities in between the observations in the charmonium and bottomonium sectors, you'll find also clear variations. In the charmonium sector, every of the Y (3915), (4040), (4160), Y (4260), Y (4360) and Y (4660) decays to only one certain final state with charmonium [ J/, J/, + - J/ or + - (2S)]. Inside the bottomonium sector, there is certainly a single state with anomalous properties, the (5S), and it decays to distinctive channels with comparable prices [ + - (nS), + - h b (m P), + - (1D), (nS)]. There is no common model describing these peculiarities. To explain the affinity from the charmonium-like states to some particular channels, the notion of "hadrocharmonium" was proposed in [1084]. It really is a heavy quarkonium embedded into a cloud of light hadron(s), therefore the fallapart decay is dominant. Hadrocharmonium could also deliver an explanation for title= jir.2014.0001 the charged charmonium-like states Z (4430)+ , Z (4050)+ and Z (4250)+ . four.three.five Summary Quarkonium spectroscopy enjoys an intensive flood of new benefits. The number of spin-singlet bottomonium states has elevated from 1 to 4 more than the final 2 years, including a far more precise measurement of your b (1S) mass, 11 MeV away in the PDG2012 typical. There is evidence for one of the two nonetheless missing narrow charmonium states anticipated ??within the area amongst the D D and D D thresholds. Observations and detailed studies from the charged bottomoniumlike states Z b (10610) and Z b (10650) and initial benefits on the charged charmonium-like states Z c open a rich phenomenological field to study exotic states near open flavor thresholds. There's also considerable progress as well as a extra clear experimental scenario for the highly excited heavy quarkonium states above open flavor thresholds. Current highlights incorporate confirmation in the Y (4140) state by CMS and D0, observation of your decays (4040, 4160) J/ by Belle, measurement on the energy dependence with the e+ e- + - h c cross section by BES III, observation of your Y (4260) X (3872) by BES III and determination on the Z (4430) spin arity from complete amplitude analysis by Belle.

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