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We examine the properties of a scalar glueball in a simple effective-Lagrangian model which satisfies both the axial-vector and trace anomaly equations of quantum chromodynamics. The scalar-glueball decay pattern can be predicted if its mass is specified and may present some unusual features. In this approach a characteristic mass scale is directly related to the vacuum energy density which automatically comes out to be of a nonperturbative type.

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A constant Yang-Mills field can be derived from either a linear Abelian gauge potential or a constant non-Abelian potential. Instabilities are known to occur for the Abelian case. In this comment, simllar effects are shown to occur for the non-Abelian case.Since the work by Mandula,' there has been considerable interest in the stability of various types of solutions of the Yang-Mills equations of motion. Mandula showed that the Coulomb solution in the presence of a static source developed instabilities when the product of the gauge coupling and the external charge exceeded some constant.' A similar criterion for instability was found by Chang and Weiss and by Sikivie3 for the case of a constant electric o r magnetic field derived from a linear gauge potential. In this case, the critical parameter is gFL2, where g is the coupling constant, F is the magnitude of the field strength, and L is the linear dimension over which the field extends.These previous considerations have involved Abelian solutions to the non-Abelian equations of motion. The potential can be lined up everywhere in a certain direction of isospin space by a gauge transformation. In this comment, I will consider an inherently non-Abelian configuration. A constant field can be derived from either a linear, Abelian gauge potential, o r a constant, non-Abelian gauge potential. This is a simple example of the Wu-Yang a m b i g~i t y .~ In gederal, different potentials which a r e associated with the same field strength can yield different physics. In particular, this is known to be true of the gauge potentials which generate constant fields. For example, the classical motion of an external particle with isospin reflects the physics of the Wu-Yang ambiguity.' Constant Yang-Mills field configurations have also attracted the attention of those who are interested in investigating the nature of the vacuum of the non-Abelian gauge theory. Motivated by the perturbative calculation of the effective Lagrangian, speculations have been made that the vacuum is characterized by a nonzero expectation value of the operator F P Y F u Y .If the vacuum is assumed to be characterized by a constant magnetic field6 o r by some modification of this configuration,' interesting physical results can be obtained, including a bound on the MIT bag con-~t a n t .~In this comment, I will study the stability of a constant non-Abelian magnetic field derived from a constant gauge potential. Similar analyses could be applied to other types of constant field configurations, but it is not my purpose to give an exhaustive treatment of the problem. For simplicity, I will only consider the SU (2) case; the Lagrangian density is c = FPya PY , (1) where the field strength tensor is The equations of motion a r e (DPFPv)a= jYa , where jVa is an external currentg and the covariant derivative is defined as D: = a Ptiab + g c a c b~; .(4) The stability of a particular configuration ( A t , FEY) is analyzed by perturbing about that configuration ( A t + 6At , F t y + 6FEY) and linearizing the equati...

We discuss the measurement of parity-violating asymmetries in polarized-proton-proton scattering at high energy as a method of extracting the hadronic decays of the intermediate vector boson from the hightransverse-momentum hadronic background. In particular we present predictions for these asymmetries for jet production through the charged and neutral vector bosons. The asymmetries are very large and the method looks promising.One of the most interesting and difficult problems in the anticipated experimental studies of the W meson i s how to measure its hadronic decays. Although the W i s expected to be produced copiously at very high energies, a s will be provided by ISABELLE,' and to decay most of the time into hadrons, the problem of extracting the signal from the high-p, hadronic background is very acute.213 Some methods have been a n a l y~e d ,~ relying on the fact that the hadrons from W decay should be richer in strange o r charmed particles than the background, but the outlook for these i s uncertain.Recent indications that it may be possible to store polarized protons in ISABELLE (Ref. 5) at high luminosity have led us to consider what seems to us the cleanest method of extracting the W signal from the background, viz., to measure high-p, jets produced with polarized protons in states of definite helicity. Because of the V-A coupling to charged W's generally assumed in the theory, only left-handed quarks will produce W's. To the extent that the quarks within the proton have their helicity correlated with the proton helicity, lefthanded protons should produce an appreciably larger number of W's than right-handed protons, and so the difference between the cross section for high p, jets produced with left-handed and righthanded protons should show a substantial W signal above a zero background from hard hadronic scattering. Many models of the spin wave function of the quarks have been proposed6 which lead to a strong correlation between valence-quark helicity and the proton helicity. These have received some experimental tests which indicate that such a correlation exists but do not clearly favor one model over the other.7 Haber and Kane have already shown that one such model, that of Carlitz and Kaur,= leads to a cross section for W' production about three times a s big from left-handed protons a s from right-handed ones.' In this paper, we would like to carry the idea a little further and calculate the expected size of the asymmetry signal for hadronic jets.The calculations in this work a r e based on the simple model of W production and decay given in Ref. 3, supplemented by the SU(6) model for the quark-spinwave function. The model i s the quarkparton model with the Drell-Yan mechanism for W production, with structure functions chosen to agree with electroproduction and lepton-pair-production data. (See Ref. 3 for a complete set of references.) We realize that there may be many corrections to this model, but we feel that for our purposes this simple approach i s adequate. Thus we do not include any tr...

Working ln the temporal gauge A, = 0, we study canonical quantlzatlon of the Hlggs model for glvlng masses to a gauge field. Thls gauge dlffers from those discussed previously ln that the symmetry of the theory 1s not spontaneously broken and the Htggs scalar field does not acqulre a vacuum expectatton value Rather, the vector meson acqulres ~t s mass through a restoration of symmetry of the vacuum under gauge transformations that do not vanlsh at spatlal mfinlty.

In a large class of gauges, including the Coulomb gauge, in non-Abelian gauge theories, an operatorordering ambiguity exists in the canonically quantized Hamiltonian. In this paper, a method is described for resolving this ambiguity. It gives rise to an extra potential-like term of order fi2.

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