A New Current Regularization of Thirring Model

We study an ambiguity of the current regularization in the Thirring model. We find a new current definition which enables to make a comprehensive treatment of the current. Our formulation is simpler than Klaiber's formulation. We compare our result with other formulations and find a very good agreement with their result. We also obtain the Schwinger term and the general formula for any current regularization.Comment: 7 pages, some comments and references added, to appear in Prog. Theor. Phy

Half-metallic diluted antiferromagnetic semiconductors

The possibility of half-metallic antiferromagnetism, a special case of ferrimagnetism with a compensated magnetization, in the diluted magnetic semiconductors is highlighted on the basis of the first principles electronic structure calculation. As typical examples, the electrical and magnetic properties of II-VI compound semiconductors doped with 3d transition metal ion pairs--(V, Co) and (Fe, Cr)--are discussed

Controlling chaos in a chaotic neural network

The chaotic neural network constructed with chaotic neuron shows the associative memory function, but its memory searching process cannot be stabilized in a stored state because of the chaotic motion of the network. In this paper, a pinning control method focused on the chaotic neural network is proposed. The computer simulation proves that the chaos in the chaotic neural network can be controlled with this method and the states of the network can converge in one of its stored patterns if the control strength and the pinning density are chosen suitable. It is found that in general the threshold of the control strength of a controlled network is smaller at higher pinned density and the chaos of the chaotic neural network can be controlled more easily if the pinning control is added to the variant neurons between the initial pattern and the target pattern

CHANGE OF TROPHIC STATUS IN LAKE SUWA DURING 20 YEARS -ELUCIDATION BY RELATIVE ABUNDANCES OF LIPID COMPOUNDS IN SEDIMENTS-

Sterols, normal alkanols, normal alkanoic acids, chlorophyll like substances, total lipid carbon, total organic carbon and C/N in the core sediment of Lake Suwa were determined. The profile of the relative abundances of these lipid compounds seemed to reflect a history of production rate in the lake during about 20 years.Article信州大学理学部付属諏訪臨湖実験所報告 7: 41-46(1991)departmental bulletin pape

Relationship between Exchangeable Acidity and Persistence of Orchardgrass (\u3ci\u3eDactylis glomerata\u3c/i\u3e) in Temperate Pastures under Different Management

Orchardgrass is a high productive, highly nutritive grass, but its persistence is low under acid soil condition. Therefore, to obtain the information on the effect of soil acidity on the persistence of orchardgrass in acid soil grasslands, we investigated the relationship between exchangeable acidity (y1) and orchardgrass in sown pastures. Eight temperate pastures (four cutting meadows [CMs] and four cattle grazing pastures [GPs]) were used for vegetation survey and soil samplings. Six or three line transects (50 m each) were fixed in each meadow or pasture, and measurement location (three quadrats 20 cm×20 cm in size and 50 cm apart from each other) was set along the transect at a 10 m interval. The most dominant plant species was recorded after first cut of the meadows in 2018. Soil samples were collected in the area around quadrats, at depth of 0–5 cm for measurement of y1 and other chemical properties. Orchardgrass was dominated in 78% and 37% of CM and GP, respectively. Tall fescue (Festuca arundinacea) was also dominated in 2% and 22% of CM and GP, respectively. In CM, the locations with higher y1 showed a tendency of higher frequency of orchardgrass (P\u3c 0.1) and significantly low frequency of tall fescue (P\u3c 0.05). In contrast in GP, soil y1 did not show significant relationship to the frequency of orchardgrass and tall fescue. Soil chemical properties such as pH, NO3-N, K2O, CaO and MgO show negative relationship to y1 (P\u3c 0.05) in CM or GP, although they did not show significant relationship to the frequency of orchardgrass. These results suggest that survival rate of orchardgrass increases with increase of y1, through preventing establishment of other plant species such as tall fescue under cutting condition, while this trend is not clear under grazing

The Diverse Stellar Populations of the W3 Star Forming Complex

An 800 sq-arcmin mosaic image of the W3 star forming complex obtained with the Chandra X-ray Observatory gives a valuable new view of the spatial structure of its young stellar populations. The Chandra image reveals about 1300 faint X-ray sources, most of which are PMS stars in the cloud. Some, but not all, of the high-mass stars producing hypercompact and ultracompact H II (UCHII) regions are also seen, as reported in a previous study. The Chandra images reveal three dramatically different embedded stellar populations. The W3 Main cluster extends over 7 pc with about 900 X-ray stars in a nearly-spherical distribution centered on the well-studied UCHII regions and high-mass protostars. The cluster surrounding the prototypical UCHII region W3(OH) shows a much smaller (<0.6 pc), asymmetrical, and clumpy distribution of about 50 PMS stars. The massive star ionizing the W3 North H II region is completely isolated without any accompanying PMS stars. In W3 Main, the inferred ages of the widely distributed PMS stars are significantly older than the inferred ages of the central OB stars illuminating the UCHIIs. We suggest that different formation mechanisms are necessary to explain the diversity of the W3 stellar populations: cluster-wide gravitational collapse with delayed OB star formation in W3 Main, collect-and-collapse triggering by shock fronts in W3(OH), and a runaway O star or isolated massive star formation in W3 North.Comment: To appear in the Astrophysical Journal. 21 pages, 5 figures. A version with high-quality figures is available at http://www.astro.psu.edu/users/edf/W3_Chandra.pd

Strong Coupling Limit of Bethe Ansatz Solutions in Massive Thirring Model

We study the strong coupling limit of the Bethe ansatz solutions in the massive Thirring model. We find analytical expressions for the energy eigenvalues for the vacuum state as well as n-particle n- hole states. This formula is compared with the numerical results and is found to achieve a very good agreement. Also, it is found that the 2-particle 2- hole and higher particle-hole states describe n- free bosons states in this limit. The behaviors of the strong coupling limit of the boson mass for various model calculations are examined. We discuss an ambiguity of the coupling constant normalization due to the current regularization.Comment: 15 pages, to appear in Ann. Phys. 281 (2000), Ma

Sustainable fruit-body formation of edible mycorrhizal Tricholoma species for 3 years in open pot culture with pine seedling hosts

The original publication is available at www.springerlink.comArticleMycoscience. 48(2): 104-108 (2007)journal articl