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Shold, enhancing our understanding in the dynamics of these systems and
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On the uPDFs in the usual gluon PDFs working with varying prescriptions. The latest analyses [1221,1222] show incredibly great agreement with J/ photoproduction information at HERA [1169?171,1185] and hadroproduction at the LHC [1142,1144,1182]. On leading of that, the J/ is predicted to be largely unpolarized, in line with all recent polarization measurements; see paragraph d in Sect. four.five.1. As for hadroproduction, the conclusions are however contrary to the author's earlier findings [1223], which show longitudinal J/ polarization and cross sections an order of magnitude beneath the CDF production information. In addition they disagree using the recent operate [1224], where J/ hadroproduction at the LHC was studied within the exact same way, comparing for the similar information [1142,1144,1182], even when the exact same uPDFs [1225,1226]2981 Web page 80 of 241 Table 14 Colour singlet model predictions for (e+ e- J/ + c ) when compared with B-factory information [1204?206]. As for the theoretical predictions for the leading-order cross section also because the corrections of order O(s ), O(v two ), and O(s v 2 ), we examine the outcomes obtained [https://dx.doi.org/10.1098/rstb.2015.0074 title= rstb.2015.0074] in [1207?209]. These calculations [https://www.medchemexpress.com/CY5-SE.html Cy5 NHS Ester site] mostly differ by various procedures of color singlet LDME determinations. As for the values of [1208], the leading-order outcomes include pure QED contributions, the O(s ) He, Fan, Chao [1207] s (2m c ) L O  (s )  (v two )  (s v 2 ) sum Belle [1204] Belle [1205] BaBar [1206] 20.0 fb 9.0 fb eight.eight fb 2.2 fbEur. Phys. J. C (2014) 74:2981 benefits involve interference terms with all the QED contributions, along with the O(v 2 ) outcomes incorporate in part a resummation of relativistic corrections, the O(s v two ) results do, even so, involve the interference terms from the O(s ) and O(v two ) amplitudes only. The short-distance coefficients of your O(s ) contribution applied in [1207] and [1208] were taken over from [1210]. The experimental cross sections refer to information samples in which at [https://dx.doi.org/10.1089/jir.2014.0001 title= jir.2014.0001] least 2, respectively 4, charged tracks had been identified Li, Wang [1209] s ( s/2) 4.381 fb five.196 fb 1.714 fb 0.731 fb 12.022 fb (4 charged tracks) s (2m c ) 7.0145 fb 7.367 fb 2.745 fb 0.245 fb 17.372 fbBodwin, Lee,Yu [1208] s ( s/2) 6.4 fb six.9 fb 2.9 fb 1.four fb 17.6+8.1 fb -6.7 33+7 ?9 fb -25.6 ?two.8 ?3.four fb (two charged tracks) 17.six ?2.8+1.5 fb (2 charged tracks) -2.were utilized. Right here, the colour singlet predictions lie once again clearly beneath the data, plus the difference was even utilized to fit the CO LDMEs of NRQCD in a kT factorization method. We note that calculations in the kT factorization scheme is often performed for any intermediate Fock state in the NRQCD v expansion. On the other hand, even a fully worked out framework of kT factorization at NLO in s couldn't cure the problem of uncanceled infrared singularities in color singlet model calculations for P wave quarkonia.tigated, as might be seen from contradicting kT factorization outcomes.
Shold, enhancing our understanding on the dynamics of those systems and offering, amongst other individuals, precision determinations of the strong coupling continual at low energies as well as the heavy quark masses. For states at and above threshold, they might at some point have the ability to ascertain the nature of your X Y Z exotic states, which includes in distinct the function that mixing among tetraquark and multihadron states plays. A probable way to address these issues that relies on lattice simulations has been pretty recently proposed in [1230,1231]. Lattice simulations are also expected for determining non-perturbative type things required in extracting the CKM matrix components |Vcb |, |Vub |, |Vcs | and |Vcd | from B D /l and D K /l decays, respectively. Present gaps involving lattice determinations and experimental fits of those form things are expected to be removed by further progress in lattice simulations. The4.5.five Existing trends in theory The most prominent candidate theory for heavy quarkonium production is NRQCD, and lots of effort is going on to prove its factorization [https://dx.doi.org/10.1098/rstb.2015.0074 title= rstb.2015.0074] theorem around the 1 hand, and to show the universality of the LDMEs by comparison to data around the other. Since at the moment you can find hints that a minimum of for the orders at the moment thought of in perturbation theory, not all information could be simultaneously described by single LDME sets, additional work might be going on to refine NRQCD calculations for [https://dx.doi.org/10.3389/fpsyg.2017.00209 title= fpsyg.2017.00209] particular observables or distinct kinematic regimes, for example the low and higher pT limits of your hadroproduction cross sections. For low pT resummation of significant logarithms, the current function [1227] followed the concept of [1228] to apply the Collins oper terman influence parameter resummation formalism [90]. For high pT resummation, the factorization theorem of [781,783] in terms of single and double parton fragmentation functions, along with the soft-collinear efficient theory approach [785,786] is often [http://besocietal.com/members/budget11velvet/activity/424084/ http://besocietal.com/members/budget11velvet/activity/424084/] applied. Other paths may be to apply transverse momentum-dependent PDFs in quarkonium production calculations, but the uncertainties inherent to these calculations will nevertheless must be completely inves-Eur. Phys. J. C (2014) 74:Page 81 of 241emergence of ensembles incorporating the effects of dynamical charm quarks in lattice calculations will assistance to establish regardless of whether charm sea contributions to charmonium spectra and to flavor observables are relevant. In the similar time, the trend to finer lattice spacings (even when at the moment somewhat displaced by a trend to carry out simulations in the physical pion mass) is likely to continue inside the extended run and can eventually enable the usage of completely relativistic b-quarks, which will give an essential cross-check on productive field theories, and sooner or later for some observables replace them. Rapid progress on the side of successful field theories is at present taking place for any technique involving heavy quarks. Numerous quantities, like spectra, decays, transitions and production cross sections, are computed within this framework with unprecedented precision inside the velocity and s expansions. Noteworthy progress is happening, in distinct, within the field of quarkonium production. Here, the recent Snowmass White Paper on "Quarkonium at the Frontiers of High Energy Physics" [1013] offers a fantastic summary.
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