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Phys. J. C (2014) 74:Web page 77 of 241ture of the J/ polarization in photoproduction emerged. In addition, no photoproduction may very well be observed at HERA. Hence, from the theory side, a new ep collider at a lot higher energies and luminosities than HERA, like possibly an LHeC, could be hugely preferred. However, there is still no NLO calculation for J/ production in deep inelastic scattering offered, as, for example, measured most recently by H1 [1171]. f. Further production observables The LHCb experiment with its specifically rich quarkonium plan has also measured absolutely new observables which nevertheless have to be exploited totally in theory tests: For the initial time in pp collisions the double J/ production cross section was measured [1172], also because 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 current in the Belle evaluation [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 recently by CDF [1176] and LHCb [1177,1178]. Exclusive production had previously been a domain of ep experiments; see [1179] to get a recent update by the H1 collaboration. A different observable for which theory predictions exist may be the J/ production price in scattering. This observable has previously been measured at LEP by DELPHI [1180] with incredibly massive uncertainties and could possibly be remeasured at an ILC. four.5.2 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. Within this section recent functions are going to be reviewed which aim at examining this universality at Next-to-Leading Order (NLO) in s . In the case of c J , these tests include things like just the top [1] order in the NRQCD v expansion, formed by the n = 3 PJ and n = 3 S 1 states. In title= jir.2014.0026 the case of 3 S1 quarkonia, these tests title= srep39151 include the terms up to relative order O(v 4 ) inside the [1] v expansion, namely the n = 3 S1 color singlet state, as [8] [8] [8] effectively as the n = 1 S0 , 3 S1 , and 3 PJ Colour Octet (CO) states; see Table 5. The momelotinib chemical information relativistic corrections involving the [1] [1] P H (three S1 ) and Q H (three S1 ) LDMEs are, nonetheless, not component of those analyses, though they are of order O(v two ) and O(v four ) within the v expansion. You'll find two reasons for that: First, the corresponding NLO calculations are far beyond the attain of existing techniques, and secondly, they're expected to provide 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 might be understood by noting that new topologies of Feynman diagrams open up when performing the transition from [1] the 3 S1 state to the CO states, but not when calculating relativistic corrections: By way of example, at top order in s the slope of your 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 three S1 state.