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In [770], a global fit of the J/ CO LDMEs to 26 sets of inclusive J/ production yield data from 10 different ppp,   , and e+ e- experiments was done; see the second column of Table 13 for the fit results. This fit describes all data, except perhaps the two-photon scattering at LEP [1180], reasonably well. This fit is overconstrained, and practically independent of possible low- pT cuts (unless such high pT cuts are chosen that all data except hadroproduction drop out of the fit [1199]). Furthermore, the resulting LDMEs are in accordance with the velocity scaling rules predicted by NRQCD; see Table 5. Thus the fit is in itself already a nontrivial test of the NRQCD factorization conjecture, especially since the high-z photoproduction region can now also be well described, which had been plagued by divergent behavior in the earlier Born analyses [1200,1201]. However, in [1197] it was shown that these CO LDME values lead to predictions of a strong transverse J/ polarization in the hadroproduction helicity frame, which is in contrast to the precise CDF [https://dx.doi.org/10.3389/fpsyg.2017.00209 title= fpsyg.2017.00209] Tevatron run II measurement [1159]; see Fig. 33d. On the other hand, in [1183] it was shown that both the measured J/ hadroproduction cross sections and the CDF run II polarization measurement [1159] can, even at the highest measured pT values, be well described when choosing one of the three CO LDME sets listed in columns four through six of Table 13. These LDMEs, however, result in predictions for e+ e- annihilation and photoproduction which are [http://kupon123.com/members/witch93laura/activity/134951/ http://kupon123.com/members/witch93laura/activity/134951/] factors four to six above the data; see Fig. 13e . Third, the calculation [1181] is the first NLO polarization analysis to include feed-down contributions. To this end, the CO LDMEs of J/, (2S) and c J were fitted to CDF [1141,1146] and LHCb [1147,1148,1182] unpolarized production data with pT > 7 GeV; see column three of Table 13. These fit results were then used for the predictions of Fig. 33e , taking the (2S) and c J feed-down con-2981 Page 78 of 241 Table 13 Overview of different NLO fits of the CO LDMEs. Analysis [770] is a global fit to inclusive J/ yield data from 10 different pp,  p, ee, and   experiments. In [1181], fits to pp yields from CDF [1141,1146] and LHCb [1147,1148,1182] were made. In [1183], three values for their combined fit to CDF J/ yield and polarization [1158,1159] data are given: A default set, and two alternative sets. Analysis [1184] is a fit to the c2 /c1 production ratio measured by CDF Butenschoen, Kniehl [770]:O [https://dx.doi.org/10.1080/17470919.2015.1029593 title= 17470919.2015.1029593] J/ (3 S1 ) /GeV[8] O J/ (1 S0 ) /GeV3 [8] O J/ (3 S1 ) /GeV3 [8] O J/ (3 P0 ) /GeV5 [1] O(2S) (3 S1 ) /GeV3 (2S) (1 S [8] ) /GeV3 O 0 [8] O(2S) (3 S1 ) /GeV3 [8] O(2S) (3 P0 ) /GeV5 [1] O0 (3 P0 ) /GeV5 [8] O0 (3 S1 ) /GeV3 [1]Eur. Phys. J. C (2014) 74:2981 [1152]. The analyses [770] and [1183] refer only to direct J/ production, and in the analyses [1181] and [1183] pT
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Phys. J. C (2014) 74:Web page 77 of 241ture on the J/ polarization
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Pic-Eur. Phys. J. C (2014) 74:Page 77 of 241ture in the J/ polarization in photoproduction emerged. In addition, no photoproduction may very well be observed at HERA. Thus, from the theory side, a new ep collider at a lot higher energies and luminosities than HERA, like possibly an LHeC, would be hugely desired. On the other hand, there's still no NLO calculation for J/ production in deep inelastic scattering available, as, for instance, measured most recently by H1 [1171]. f. Further production observables The LHCb experiment with its especially wealthy quarkonium program has also measured fully new observables which nonetheless need to be exploited fully in theory tests: For the very first time in pp collisions the double J/ production cross section was measured [1172], also as the production of J/ in association with charmed mesons [1173]. Like double charmonium production, J/ + cc was previously only measured at the B factories, most recent in the Belle analysis [1174], which was crucial for testing J/ production mechanisms in e+ e- production. J/ production in association with W bosons has for the first time been measured by the ATLAS collaboration [1175]. Exclusive charmonium hadroproduction has been observed lately by CDF [1176] and LHCb [1177,1178]. Exclusive production had previously been a domain of ep experiments; see [1179] for any current update by the H1 collaboration. Yet another observable for which theory predictions exist is [http://www.musicpella.com/members/versebolt6/activity/472206/ http://www.musicpella.com/members/versebolt6/activity/472206/] definitely the J/ production rate in  scattering. This observable has previously been measured at LEP by DELPHI [1180] with pretty big uncertainties and could possibly be remeasured at an ILC. 4.5.2 NLO tests of NRQCD LDME universality The phenomenological relevance of the NRQCD factorization conjecture is closely tied towards the question of irrespective of whether or not the LDMEs might be shown to become universal. Within this section current performs will probably be reviewed which aim at examining this universality at Next-to-Leading Order (NLO) in s . Within the case of c J , these tests include things like just the major [1] order of your NRQCD v expansion, formed by the n = 3 PJ and n = 3 S 1 states. In [https://dx.doi.org/10.1089/jir.2014.0026 title= jir.2014.0026] the case of three S1 quarkonia, these tests [https://dx.doi.org/10.1038/srep39151 title= srep39151] involve the terms as much as relative order O(v four ) in the [1] v expansion, namely the n = 3 S1 colour singlet state, as [8] [8] [8] effectively because the n = 1 S0 , three S1 , and 3 PJ Colour Octet (CO) states; see Table 5. The relativistic corrections involving the [1] [1] P H (3 S1 ) and Q H (3 S1 ) LDMEs are, having said that, not component of these analyses, though they're of order O(v two ) and O(v 4 ) inside the v expansion. You'll find two reasons for that: 1st, the corresponding NLO calculations are far beyond the attain of present approaches, and secondly, they're expected to offer important contributions to hadroproduction only at m c and for photoproduction only at z  1. This behavpT ior is inferred in the behavior at LO in s [1187,1188][8]and might be understood by noting that new topologies of Feynman diagrams open up when performing the transition from [1] the 3 S1 state towards the CO states, but not when calculating relativistic corrections: For example, at leading order in s the slope on the transverse momentum distribution in [1] -8 hadroproduction is d/dpT  pT for the 3 S1 state, com[8] [8] -6 pared to d/dpT  pT for the 1 S0 and three PJ states and [8] -4 d/dpT  pT for the 3 S1 state.

Версия 14:06, 2 января 2018

Phys. J. C (2014) 74:Web page 77 of 241ture on the J/ polarization Pic-Eur. Phys. J. C (2014) 74:Page 77 of 241ture in the J/ polarization in photoproduction emerged. In addition, no photoproduction may very well be observed at HERA. Thus, from the theory side, a new ep collider at a lot higher energies and luminosities than HERA, like possibly an LHeC, would be hugely desired. On the other hand, there's still no NLO calculation for J/ production in deep inelastic scattering available, as, for instance, measured most recently by H1 [1171]. f. Further production observables The LHCb experiment with its especially wealthy quarkonium program has also measured fully new observables which nonetheless need to be exploited fully in theory tests: For the very first time in pp collisions the double J/ production cross section was measured [1172], also as the production of J/ in association with charmed mesons [1173]. Like double charmonium production, J/ + cc was previously only measured at the B factories, most recent in the Belle analysis [1174], which was crucial for testing J/ production mechanisms in e+ e- production. J/ production in association with W bosons has for the first time been measured by the ATLAS collaboration [1175]. Exclusive charmonium hadroproduction has been observed lately by CDF [1176] and LHCb [1177,1178]. Exclusive production had previously been a domain of ep experiments; see [1179] for any current update by the H1 collaboration. Yet another observable for which theory predictions exist is http://www.musicpella.com/members/versebolt6/activity/472206/ definitely the J/ production rate in scattering. This observable has previously been measured at LEP by DELPHI [1180] with pretty big uncertainties and could possibly be remeasured at an ILC. 4.5.2 NLO tests of NRQCD LDME universality The phenomenological relevance of the NRQCD factorization conjecture is closely tied towards the question of irrespective of whether or not the LDMEs might be shown to become universal. Within this section current performs will probably be reviewed which aim at examining this universality at Next-to-Leading Order (NLO) in s . Within the case of c J , these tests include things like just the major [1] order of your NRQCD v expansion, formed by the n = 3 PJ and n = 3 S 1 states. In title= jir.2014.0026 the case of three S1 quarkonia, these tests title= srep39151 involve the terms as much as relative order O(v four ) in the [1] v expansion, namely the n = 3 S1 colour singlet state, as [8] [8] [8] effectively because the n = 1 S0 , three S1 , and 3 PJ Colour Octet (CO) states; see Table 5. The relativistic corrections involving the [1] [1] P H (3 S1 ) and Q H (3 S1 ) LDMEs are, having said that, not component of these analyses, though they're of order O(v two ) and O(v 4 ) inside the v expansion. You'll find two reasons for that: 1st, the corresponding NLO calculations are far beyond the attain of present approaches, and secondly, they're expected to offer important contributions to hadroproduction only at m c and for photoproduction only at z 1. This behavpT ior is inferred in the behavior at LO in s [1187,1188][8]and might be understood by noting that new topologies of Feynman diagrams open up when performing the transition from [1] the 3 S1 state towards the CO states, but not when calculating relativistic corrections: For example, at leading order in s the slope on the transverse momentum distribution in [1] -8 hadroproduction is d/dpT pT for the 3 S1 state, com[8] [8] -6 pared to d/dpT pT for the 1 S0 and three PJ states and [8] -4 d/dpT pT for the 3 S1 state.