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Pic-Eur. Phys. J. C (2014) 74:Web page 77 of 241ture in the J/ polarization Pic-Eur. Phys. J. C (2014) 74:Web page 77 of 241ture of the J/ polarization in photoproduction emerged. Moreover, no photoproduction may very well be observed at HERA. Consequently, from the theory side, a new ep collider at considerably greater energies and luminosities than HERA, like possibly an LHeC, would be highly preferred. However, there is certainly nonetheless no NLO calculation for J/ production in deep inelastic scattering readily available, as, one example is, measured most not too long ago by H1 [1171]. f. Further production observables The LHCb experiment with its especially rich quarkonium system has also measured absolutely new observables which still need to be http://nevawipe.com/members/eight1author/activity/236016/ exploited fully in theory tests: For the initial time in pp collisions the double J/ production cross section was measured [1172], as well as the production of J/ in association with charmed mesons [1173]. Like double charmonium production, J/ + cc was previously only measured in the B factories, latest in the Belle evaluation [1174], which was vital for testing J/ production mechanisms in e+ e- production. J/ production in association with W bosons has for the very 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] to get a current update by the H1 collaboration. Yet another observable for which theory predictions exist will be 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.five.two NLO tests of NRQCD LDME universality The phenomenological relevance on the NRQCD factorization conjecture is closely tied towards the query of whether or not or not the LDMEs can be shown to become universal. In this section current performs will likely 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 leading [1] order in the NRQCD v expansion, formed by the n = three PJ and n = 3 S 1 states. In title= jir.2014.0026 the case of 3 S1 quarkonia, these tests title= srep39151 include things like the terms up to relative order O(v 4 ) within the [1] v expansion, namely the n = 3 S1 colour singlet state, as [8] [8] [8] nicely as the n = 1 S0 , three S1 , and 3 PJ Colour Octet (CO) states; see Table five. The relativistic corrections involving the [1] [1] P H (three S1 ) and Q H (three S1 ) LDMEs are, nevertheless, not portion of these analyses, while they may be of order O(v 2 ) and O(v 4 ) inside the v expansion. You will find two motives for that: First, the corresponding NLO calculations are far beyond the attain of present techniques, and secondly, they are anticipated to give significant contributions to hadroproduction only at m c and for photoproduction only at z 1. This behavpT ior is inferred from the behavior at LO in s [1187,1188][8]and can be understood by noting that new topologies of Feynman diagrams open up when undertaking the transition from [1] the three S1 state for the CO states, but not when calculating relativistic corrections: One example is, at major order in s the slope in the transverse momentum distribution in [1] -8 hadroproduction is d/dpT pT for the three 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.