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High field ESR measurements under pressure have been performed on the spin gap system TlCuCl 3 which is well known to show the field induced order. We observed an anomaly in the magnetic field dependence of the g-value of TlCuCl 3 and found that the anomaly corresponds to the phase transition field from the paramagnetic phase to the field induced order phase. It also turned out that ESR in the paramagnetic phase should be explained by considering the effective crystal field anisotropy. Moreover, the decrease of the critical magnetic field under pressure was observed.

High field ESR measurements of powder and aligned samples of MCuP 2 O 7 (M = Sr, Pb) have been performed in the temperature range from 1.7 K to 265 K in the frequency range from 40 GHz to 370 GHz. A typical powder absorption line of Cu 2+ is observed in the powder sample. In the higher temperature region, g∥ and g⊥ are estimated to be 2.40 and 2.10 for SiCuP 2 O 7 and 2.41 and 2.09 for PbCuP 2 O 7 , respectively. Both g∥ and g⊥ increase with decreasing temperature below 7 K. We have found that the shift direction is inconsistent with the ESR theory of Nagata-Tazuke for the one dimensional antiferromagnet. We have also found that the shifts have frequency dependence.

High field ESR measurements of the one dimensional (1D) spin gap system Pb 2 V 3 O 9 have been performed in the frequency region from 120 to 364 GHz in order to examine the magnetic properties of this compound. In the low temperature region we have observed ESR signals in both the paramagnetic phase and the high field phase above the critical field He'These ESR signals show the characteristic features in each phase, indicating that Pb 2 V 3 O 9 undergoes the field-induced magnetic ordering above H c .

The EPR spectra along different crystallographic axes for single crystals of CuGeO3 containing 1% of Fe impurity have been studied in the frequency range 60-360 GHz at temperatures 0.5-30 K. The analysis based on the Oshikawa-Affleck (OA) theory suggests that the temperature dependences of the line width and g-factor are formed as a result of the competition between interchain antiferromagnetic interactions and staggered Zeeman energy. It is found that staggered magnetic moments in CuGeO3:Fe are located predominantly along b axis., Comment: 9 pages, 4 figures; submitted to QSS04 symposium

High field ESR measurements of the distorted S = 1/2 diamond chain substance Cu 3 )(CO 3 ) 2 (OH) 2 have been performed in the frequency region from 50 to 1000 GHz at 1.9 K using the pulsed magnetic field up to 36 T. The ESR signals of the direct transition from the singlet ground state to the excited state have been observed for B∥a, b and c axes. As the direct transition is essentially forbidden in ESR, the signal can be observed due to the Dzyaloshinsky-Moriya (DM) interaction. The angular dependence of the direct transition intensity has been measured in order to investigate the D vector of the DM interaction. This paper shall discuss the D vector in connection with the theoretical calculation for the anisotropic ESR signal intensity of the direct transition.

To investigate both the incidence and the dosage used to treat gastrointestinal (GI) symptoms associated with enteric-coated sulfasalazine (Azulfidine EN, AZL) in patients with rheumatoid arthritis (RA), we studied the clinical history of 153 RA patients, and any available data on GI symptoms that might have been associated with AZL. GI symptoms appeared in 64 (42.5%) of the 153 cases. There were 19 events of nausea, vomiting, or dyspepsia, 14 events each of epigastric discomfort and reduction or loss of appetite, 10 events of epigastric, stomach, or abdominal pain, 9 events of heartburn, 8 events of mouth ulcer, 3 events each of loss of taste and abdominal bloating or borborygmus, 2 events each of diarrhea or loose stools, hematemesis or melanemia, and gastric or esophageal ulcer, and 1 event of stomatitis. These results indicate that GI symptoms associated with AZL are usually mild and treatment can continue, with almost all cases responding to a reduction in dose or drug cessation. In some cases, a histamine receptor-2 blocker or proton pump inhibitor is also required.

Recent advance of a field theoretical approach of a low-temperature electron spin resonance (ESR) in S=½ antiferromagnetic chain, which has Dzyaloshinskii-Moriya (DM) interactions and staggered g-tensor sites, by Oshikawa and Affleck (OA) suggests peculiar magnetic field dependence of ESR. Although BaCu 2 (Si 1 - x Ge x ) 2 O 7 is an antiferromagnetic chain system with mixed antiferromagnetic and ferromagnetic interchain interactions, we found that x=0.65 substance shows the peculiar field dependence of ESR predicted by OA theory. The temperature dependence of the line width showed the power-law dependence and strong field dependence in the gapless spinon regime which can be well interpreted by OA theory. The temperature dependence of the resonance shift turned out to be also consistent with OA theory. These results are also discussed in connection with Cu-Benzoate which is considered as a model substance of OA theory.

Based upon the BRST formulation of covariant quantization of QCD and assuming that the PCT operator is well defined, we present a plausibility argument that the so-called θ parameter for the strong CP violation of QCD should be equal identically to θ=0 or π

On propose que la γ-algebre de Dirac-Clifford soit modifiee pour devenir non associative. L'algebre non associative resultante est Lie-admissible avec involution et avec operation de trace cyclique

Dispersion relations for the photoproduction of K mesons by nucleons sre derived both covariantly and non-covariantly. They contain the renormalized Born term with inclusion of the magnetic moments of baryons.

A classification of the baryon isobars has been investigated on basis of the unitary symmetry model which has been developed in a previous paper under the same title.

The dispersion relation for ith Cr deposite -N scattering is applied in calculating the two-body spin-orbit potential. Numerical results obtained are not in close agreement with the shell model as to magnitude and sign.

A formalism where Hamiltonian is generally diagonalised is given and the relation of this formalism to the Tamm-Dancoff equation is studied. The Tamm-Dancoff equation in which the energy of the system appearing in the denominator of the equation is eliminated, can be obtained from the solution of a differential equation. In this energy-eliminated Tamm-Dancoff equation, the subtraction of closed loops is possible. Furthermore, some applications are given.

Assuming invariance of a theory under three-dimensional unitary group, various consequences are investigated. Both the Sakata and Gell-Mann schemes can be treated in this fashion in a simple way. A mass formula for particles belonging to the same irreducible representation is derived and compared with experiments. (auth)