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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/ 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.

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