Photoproduction of J/ is considered including the color-octet contributions from the various partial wave states, 2Sϩ1 L J ϭ 1 S 0 , 3 S 1 , and 3 P J . The production cross section depends on three new nonperturbative parameters defined in NRQCD, called the color-octet matrix elements. Using the color-octet matrix elements determined by fitting the J/ production at the Fermilab Tevatron, we find that the color-octet (cc) 8 ( 1 S 0 and 3 P J ) contributions to the J/ photoproduction at the fixed target experiments and at DESY HERA are too large compared to the data on (␥ϩp→J/ϩX) in the forward direction, and the z distribution of J/. The P T 2 distribution of J/ and the total inelastic J/ production rate as a function of ͱs ␥p are predicted including color-octet contributions. We also briefly digress on the B→J/ϩX and observe the similar situation. This may be an indication that the color-octet matrix elements determined from the J/ production at the Tevatron, especially ͗0͉O 8( 1 S 0 )͉0͘ and ͗0͉O 8 ( 3 P J )͉0͘, might have been overestimated by an order of magnitude.These inequalities can provide us with some predictions on various quantities related with inclusive J/ productions in other high energy processes, which enables us to test the idea of color-octet mechanism.Since the color-octet mechanism in heavy quarkonium production is an idea proposed in order to resolve the Ј anomaly at the Tevatron, it is important to test this idea in *Electronic address: pko@phyb.snu.ac.kr † Electronic address: jungil@phyb.snu.ac.kr ‡ Electronic address: hssong@physs.snu.ac.kr PHYSICAL
We investigate the associated production of neutralinos e ϩ e Ϫ → 1 0 2 0 accompanied by the neutralino leptonic decay 2 0 → 1 0 l ϩ l Ϫ , taking into account initial beam polarization and production-decay spin correlations in the minimal supersymmetric standard model with general CP phases but without generational mixing in the slepton sector. The stringent constraints from the electron EDM on the CP phases are also included in the discussion. Initial beam polarizations lead to three CP-even distributions and one CP-odd distribution, which can be studied independently of the details of the neutralino decays. We find that the production cross section and the branching fractions of the leptonic neutralino decays are very sensitive to the CP phases. In addition, the production-decay spin correlations lead to several CP-even observables such as lepton invariant mass distribution, and lepton angular distribution, and one interesting T-odd (CP-odd͒ triple product of the initial electron momentum and two final lepton momenta, the size of which might be large enough to be measured at the high-luminosity future electron-positron collider or can play a complementary role in constraining the CP phases with the EDM constraints.PACS number͑s͒: 14.80.Ly, 12.60.Jv, 13.85.Qk 0 may be, for some time, the only chargino and neutralino PHYSICAL REVIEW D, VOLUME 61, 075004
Polarized heavy quarkonium productions in Z 0 decays are considered. We find that polarizations of the produced quarkonia are independent of that of the parent Z 0 provided that one considers the energy distribution or the total production rate. Produced J/'s via the color-octet and the color-singlet mechanisms are expected to be 19% and 29% longitudinally polarized, respectively. The energy dependence of 1,8 (x) ϵ d⌫ 1,8 L /dx/d⌫ 1,8 /dx is very sensitive to the production mechanism, and, therefore, the measurement of (x) expt will be an independent probe of the color-octet mechanism. ͓S0556-2821͑97͒04511-6͔
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