Spin alignment of vector meson in e+e- annihilation at Z0 pole

We calculate the spin density matrix of the vector meson produced in e+e- annihilation at Z^0 pole. We show that the data imply a significant polarization for the antiquark which is created in the fragmentation process of the polarized initial quark and combines with the fragmenting quark to form the vector meson. The direction of polarization is opposite to that of the fragmenting quark and the magnitude is of the order of 0.5. A qualitative explanation of this result based on the LUND string fragmentation model is given.Comment: 15 pages, 2 fgiures; submitted to Phys. Rev.

Spin Alignment of Vector Meson in High Energy Reactions

The recent data on the polarization of vector meson at LEP show that the vector mesons favor the helicity zero state. We calculate the helicity density matrix of vector meson which contains a polarized fragmenting quark by adding the spin of the fragmenting quark and that of the antiquark created in the fragmentation. The data at LEP imply a significant polarization for the antiquark in the opposite direction as that of the fragmenting quark. We extend the calculations to other reactions and make predictions for vector mesons in deeply inelastic lepton-nucleon scatterings and polarized $pp$ collisions.Comment: 4 pages,3 figures, Talk given at 3rd Circum-Pan-Pacific Symposium on "High Energy Spin Physics", Beijing, China, Oct.8-13, 200

catena-Poly[[aqua­(dipyrido[3,2-a:2′,3′-c]phenazine-κ2 N 4,N 5)iron(II)]-μ-pyrazine-2,3-dicarboxyl­ato-κ3 N 1,O 2:O 3]

In the title compound, [Fe(C6H2N2O4)(C18H10N4)(H2O)]n, the FeII ion adopts a slightly distorted octahedral mer-FeN3O3 geometry, arising from one N,N′-bidentate dipyrido[3,2-a:2′,3′-c]phenazine ligand, one N,O-chelating pyrazine-2,3-dicarboxyl­ate dianion and one water mol­ecule. An O-bonded symmetry-related dianion completes the coordination of the metal. The bridging dianion results in a one-dimensional polymeric chain. Aromatic π–π stacking inter­actions between ligands [centroid–centroid separations = 3.528 (2) and 3.741 (2) Å] and O—H⋯O and O—H⋯N hydrogen bonds link the chains together, leading to a three-dimensional supra­molecular network

catena-Poly[[aqua­(pyrazino[2,3-f][1,10]phenanthroline-κ2 N 8,N 9)cobalt(II)]-μ-pyrazine-2,3-dicarboxyl­ato-κ3 N 1 O 2:O 3]

In the title compound, [Co(C6H2N2O4)(C14H8N4)(H2O)]n, the Co atom is bonded to one N,N′-bidentate pyrazino[2,3-f][1,10]phenanthroline (Pyphen) ligand, one N,O-bidentate pyrazine-2,3-dicarboxyl­ate (PZDC) dianion and one water mol­ecule in a distorted octa­hedral mer-CoN3O3 geometry. The CoII atoms are bridged by the PZDC dianions, forming an infinite one-dimensional chain running along the b axis. Adjacent chains pack together through π–π stacking inter­actions [centroid–centroid separations = 3.498 (4) and 3.528 (4) Å], and O—H⋯O and O—H⋯N hydrogen bonds involving the water mol­ecule complete the structure

The sequence flanking the N-terminus of the CLV3 peptide is critical for its cleavage and activity in stem cell regulation in Arabidopsis

The "Shakespeare Authorship Question"—regarding the identity of the poet-playwright—has been debated for over 150 years. Now, with the growing list of signatories to the "Declaration of Reasonable Doubt," the creation of a Master's Degree program in Authorship Studies at Brunel University in London, the opening of the Shakespeare Authorship Research Studies Center at the Library of Concordia University in Portland, and the release of two competing high-profile books both entitled Shakespeare Beyond Doubt, academic libraries are being presented with a unique and timely opportunity to participate in and encourage this debate, which has long been considered a taboo subject in the academy.https://journal.lib.uoguelph.ca/index.php/perj/article/view/280

Geochemical characteristics of biogenic barium in sediments of the Antarctica Ross Sea and their indication for paleoproductivity

241-248In this paper, the biogenic Ba of Column R11 in the Antarctic Ross Sea and its implications to the paleo oceanographic productivity since the late of Late Quaternary were discussed, combined with the organic carbon, opal and biogenic calcium carbonate. The biogenic Ba contents ranged from 51.8 to 508.4 μg/g overall, exhibiting a gradually rising trend from the bottom to the top. It highly correlated both with TOC and opal, revealing that on one hand biogenic Ba can be used to study the change of productivity in the Ross Sea; and on the other hand, the marine productivity gradually increased since the late Pleistocene. The new productivity based on Francois model varied from 0.40 to 233.90 gC/(m2•a). The high values were mainly concentrated at the depth from 32 to 48 cm, but the new productivity values of the bottom were lower. It was inferred that the change in marine productivity in the Ross Sea was possibly affected by the ice cover since the late Pleistocene