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Zation conjecture has by now received most acceptance, although not but becoming totally established. 4.5.1 Summary of recent experimental progress The past couple of years have seen extraordinary progress in measurements of quarkonium production observables, which was mostly, but not solely, due to the operation of your various LHC experiments. Here we'll give an overview from the most exceptional outcomes of your previous years. The production prices of a heavy quarkonium H are split into direct, prompt, and nonprompt contributions. Direct production refers to the production of H straight at the interaction point from the initial particles, even though prompt production also involves production by way of radiative [http://lisajobarr.com/members/coilinput8/activity/755824/ http://lisajobarr.com/members/coilinput8/activity/755824/] decays of greater quarkonium states, called feed-down contributions. Nonprompt production refers to all other production mechanisms, mostly the production of charmonia from decaying B mesons, which could be 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 of the J/ production cross section [1141] is still among probably the most precise heavy quarkonium production measurements. But since theory errors in all models for heavy quarkonium production are still substantially larger than today's experimental errors, it really is in general not greater precision that is 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 is exactly where the LHC experiments have provided very important input. As for the J/ hadroproduction cross section, they've extended the CDF measurement [1141] into new kinematic regions: Of course, the measurements have already been performed at much greater center-of-mass energies than before, namely at s = two.76, 7, and 8 TeV. But a lot more vital for testing quarkonium production models will be the fact that there are actually measurements which exceed the previously measured pT variety each at higher pT , as by ATLAS [1142] and CMS [1143], and at low pT , as inside the earlier CMS measurement [1144], but in addition within the recent measurement by the PHENIX collaboration at RHIC [1145]. We note that this list just isn't complete, and that there have been numerous far more J/ hadroproduction measurements not too long ago than these cited right here. b. (2S) and c production in pp collisions J/ is the quarkonium that is easiest to be measured as a consequence of thelarge branching ratio of its leptonic decay modes, but in current years, higher precision measurements have already been also performed for the (2S), namely by the CDF [1146], the CMS [1143], as well as the LHCb [1147] collaborations. Also the c production cross sections had been measured by means of their decays into J/ by LHCb [1148], the first time because 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 good significance for the theory side because they let fits of NRQCD LDMEs for these charmonia and figure out direct J/ production data, which can in turn be in comparison with direct production theory predictions. c. production in pp collisions (1S), (2S), and (3S) production cross sections had been measured in 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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