How to find ηc and a possible state cc̅ cc̅

In order to test the existence of X(2.8) and the validity of interpreting it as a pseudoscalar cc̅ meson, and also to test the existence of a possible state cc̅ cc̅, it is proposed to measure the recoil-mass spectrum against J/ψ(3.1) at the c.m. energy about 6 GeV in e+e- annihilation. This also serves to check the Okubo-Zweig-Iizuka rule

Consistency Condition for Propagators

It is shown that there is a strict condition for the propagators of higher-spin particles. We require the consistency of the propagator when a particle propagates by means of self-energy-type interactions. We require a kind of unitarity. Then this requirement turns out to be a strict condition in the case of higher-spin particles. Its nontriviality is due to the fact that free fields of higher-spin particles contain redundant components, which are suppressed by means of subsidiary conditions, not satisfied by the currents coupled with the fields. The usual propagators do not satisfy our requirement, while those which have been introduced in connection with the O(4) symmetry satisfy it. Also, a difficulty of the scalar-tensor theory of the graviton is pointed out

センヨウ ヘイレツ ケイサンキ ニヨル バ ノ ブツリ ノ ケンキュウ

平成元年の学術審議会建議に基づき,平成2年度から｢学術の新しい展開のためのプログラム｣(略称新プログラム)が発足した.ここに研究成果を報告する｢専用並列計算機による｢場の物理｣の研究｣は,その実施テーマの一つとして ...付属資料: 主要論文別刷集研究課題番号: 08NP0101研究代表者: 岩崎洋

Two kinds of the mass of the charmed quark

It is argued that when a pair of a charmed quark and a charmed antiquark is produced via one photon, the mass of the charmed quark is to be light, i.e., roughly 500 MeV, quite contrary to the heavy mass usually assumed. It is thus proposed that we have to discriminate between, at least, two kinds of the mass of the charmed quark that are exhibited in different situations

Quantization of a String of Spinning Material—Hamiltonian and Lagrangian Formulations

The dynamics of a relativistic string made of spinning material is discussed in two different formulations. The first is a manifestly covariant formulation under a gauge transformation. The second is a Hamiltonian formalism which enables us to make the transition from the classical to the quantum description in a coherent way. The Lagrangian is also constructed. The results of our investigations are as follows: (1) The mass spectra here coincide with those of the Neveu-Schwarz model. (2) The model is ghost-free. (3) The Poincaré generators Mμν and Pμ are constructed. The quantization is shown to be consistent with Lorentz covariance if the dimension of space-time is 10 and the Regge intercept is ½

Phase structure of lattice QCD for general number of flavors

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First Nonperturbative Test of a Relativistic Heavy Quark Action in Quenched Lattice QCD

We perform a numerical test of a relativistic heavy quark(RHQ) action, recently proposed by Tsukuba group, in quenched lattice QCD at $a\simeq 0.1$ fm. With the use of the improvement parameters previously determined at one-loop level for the RHQ action, we investigate a restoration of rotational symmetry for heavy-heavy and heavy-light meson systems around the charm quark mass. We focused on two quantities, the meson dispersion relation and the pseudo-scalar meson decay constants. It is shown that the RHQ action significantly reduces the discretization errors due to the charm quark mass. We also calculate the S-state hyperfine splittings for the charmonium and charmed-strange mesons and the $D_s$ meson decay constant. The remaining discretization errors in the physical quantities are discussed.Comment: 21 pages, 16 figures. A reference and a comment added, a major modification in appendix, several minor changes in the abstract and the main text. Errors in affiliation are corrected. Version appeared in JHE

Proton decay and lattice QCD

Proton decay rates in grand unified theories are calculated by using numerical results obtained by Monte Carlo simulation in lattice QCD. The decay rates are calculated in such a way that they are independent on the renormalization point. By comparing the theoretical and experimental results on p→π0e+ decay, we conclude that the simple SU(5) model is excluded as a realistic model

K+→π+π0 decay amplitude with the Wilson quark action in quenched lattice QCD

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Scaling study of the two-flavor chiral phase transition with the Kogut-Susskind quark action in lattice QCD

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