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Pic-Eur. Phys. J. C (2014) 74:Page 77 of 241ture in the J/ polarization Pic-Eur. Phys. J. C (2014) 74:Page 77 of 241ture from the J/ polarization in photoproduction emerged. Moreover, no photoproduction may be observed at HERA. Consequently, from the theory side, a brand new ep collider at a lot greater energies and luminosities than HERA, like possibly an LHeC, would be very desired. Alternatively, there is certainly nonetheless no NLO calculation for J/ production in deep inelastic scattering accessible, as, by way of example, http://www.musicpella.com/members/babies66trade/activity/527192/ measured most lately by H1 [1171]. f. Further production observables The LHCb experiment with its specifically wealthy quarkonium plan has also measured totally new observables which still need to be exploited completely in theory tests: For the initial time in pp collisions the double J/ production cross section was measured [1172], as well because the production of J/ in association with charmed mesons [1173]. Like double charmonium production, J/ + cc was previously only measured in the B factories, most recent in the Belle analysis [1174], which was critical 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] for a current update by the H1 collaboration. One more observable for which theory predictions exist is definitely the J/ production price in scattering. This observable has previously been measured at LEP by DELPHI [1180] with pretty significant uncertainties and could possibly be remeasured at an ILC. four.5.2 NLO tests of NRQCD LDME universality The phenomenological relevance in the NRQCD factorization conjecture is closely tied for the query of whether or not the LDMEs might be shown to be universal. Within this section recent operates might be reviewed which aim at examining this universality at Next-to-Leading Order (NLO) in s . In the case of c J , these tests consist of just the leading [1] order with the NRQCD v expansion, formed by the n = three PJ and n = three S 1 states. In title= jir.2014.0026 the case of three 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] well because the n = 1 S0 , three S1 , and three PJ Colour Octet (CO) states; see Table 5. The relativistic corrections involving the [1] [1] P H (three S1 ) and Q H (3 S1 ) LDMEs are, having said that, not portion of those analyses, while they may be of order O(v two ) and O(v four ) in the v expansion. You will discover two causes for that: Very first, the corresponding NLO calculations are far beyond the reach of existing techniques, and secondly, they're anticipated to give considerable 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 could 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: As an example, at major order in s the slope of your 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.