Recent content by BuckeyePhysicist

Why in PDG booklet, gluon has J^{PC} value as 1^-, where C is abscent?

How to form a J^{PC} = 1^{--} state with only gluons? Two gluons? Three ? How do the P, C, J values work?

I am told that glueball has a distincitve feature that is enhanced production in gluon-rich channels such as central production and radiative J/\psi decay. Could someone break these up a little for me? What is central production? How radiative J/\psi decay is a gluon-rich channel? THanks.

Could some one explain the definition of diquark in hep-ph/0307243 to me? Why it is necesary/useful to have it in SU(3)_f 3-bar representation?

What is QCD sum rule(s)?

It is relevant. But it does not answer the question. Thank you any way.

Is a baryonium baryon or meson? For example, deutorium, a n-p bound-state, has total spin 0 pr 1, so it is boson, then, it is meson? But it has baryon number (3+3)/3=2. For another example, bound-state of \Lambda_c - \bar{\Lambda_c}, has total spin 0 or 1, so again it is boson, it is meson...

NRQCD expends in powers of (\alpha/v)^n but not \beta ? \beta = v/c where v is the relative velocity of the two heavy quark constituents for quarkonium. \beta ~ 0.3 for charmonium and \beta ~0.1 for bottomonium, right?

What is the relationship between pQCD and NRQCD? Is it that pQCD is for high energy/short-distance regime, e.g. quark gluon plasma? And NRQCD is for low energy/long-distance regime, e.g. quarkonium ? And what is relation between heavy quark effective theory and pQCD and that between heavy...

How is it not an exactly accurate understanding that QCD is a part/sector of the standard model of particle physics ? Or, it actually is?

Thanks for the helpful answer. Could you at least give me one concrete example? If I want a totally antisymmetric diquark which has flavor content u and d, how it should look like?

Is a diquark $ [q_1q_2]$ a totally antisymmetric state in color, flavor and spin space, i.e. a color antitriplet $\overline{3}_c$, flavor antitriplet $\overline{3}_f$ and spin singlet? So if it has u, d flavors, how to write it explicitely? $ |ud -du \rangle \otimes...

Well, I konw we understand QCD better. But could a few specific items be listed, sort of?

[URGENT]How to prove gluon has this quantum number assignment? From PDG booklet, for gluon, I^G(J^{PC}) = 0(1^-). My questions are: 1. How to prove its P=-1? 2. Why C parity and therefore G parity are not well-defined for a gluon? Is it because gluon have nothing to do with...

What if I couple q_1 q_2 first with total angular momentum quantum number: J_1, and couple \bar q_1 and \bar q_2 together with J_2. And at last couple the diquark with the anti-diquark[or di-antiquark] with orbital momentum L. What I get for C for this tetraquark? Is it (-1)^2 * (-1)^{J_1+1}*...