Photon transitions in Upsilon(2S) and Upsilon(3S) decays

We have studied the inclusive photon spectra in Upsilon(2S) and Upsilon(3S) decays using a large statistics data sample obtained with the CLEO III detector. We present the most precise measurements of electric dipole (E1) photon transition rates and photon energies for Upsilon(2S) --> gammachi(bJ)(1P) and Upsilon(3S) --> gammachi(bJ)(2P) (J = 0, 1, 2). We measure the rate for a rare E1 transition Upsilon(3S) --> gammachi(b0)(1P) for the first time. We also set upper limits on the rates for the hindered magnetic dipole (M1) transitions to the eta(b)(1S) and eta(b)(2S) states.     

Overcrowded molecules. V. 3,10-dimethyl-1,12-bis(2-pyridyl)benzo[c] phenanthrene-2,11-diol

The bis ketene acetal adduct of 4a,10a-diazoniaanthra[1,2-α]anthracene diperchlorate ( 10 ) was used to prepare the highly overcrowded benzo[c]phenanthrene 2 by a known procedure. Its oxidation with cupric chloride provided the isoxazolium zwitterion, 3 , via an intramolecular cyclization.     

Model for predicting the composition of copolyesters: Polymerization of terephthalic acid, 2,2′-oxydiethanol,and 2,2-dimethyl-1,3-propanediol

Copolyesters of two glycols and a dicarboxylic acid moiety are frequently made to obtain specific physical properties. In the synthesis of these polymers an excess of glycol is used in the ester-exchange reaction and then removed during the polycondensation reaction to form a high-molecular-weight product. A model has been developed to predict the final polymer composition. The derivation is based on equilibria of reaction species (free glycol, polymer chain ends, and ester links) and the relative vapor pressures of the two reacting glycols. Calculated results are compared with experimental results of poly(2,2′-oxydiethylene: 2,2-dimethyl-1,3-propylene terephthalate)s. There is good agreement between calculated and experimental compositions. The model can be used to calculate the glycol concentrations that must be used to make a specific polymer composition. This model should also be useful in the calculation of other mole ratios of glycol to dicarboxylic acid that will make the same composition.     

A new method for the synthesis of fused 3-amino-s-triazole ring systems

Reaction of 2-methyl-2-thiopseudourea sulfate with 1-hydrazinophthalazine gave 3-amino-s-triazolo[3,4-a] phthalazine in good yield. 1-Amino-4-methyl-s-triazolo[4,3-a]quinoxaline and 1-amino-s-triazolo[4,3-a]quinoxalin-4(5H)one were similarly perpared.     

Improved measurement of B(D+ --> mu+nu) and the pseudoscalar decay constant fD+

We extract a relatively precise value for the decay constant of the meson by measuring B(D+ --> mu+nu) = (4.40 +/-0.66(+0.09)(-0.12) x 10(-4) using 281 pb(-1) of data taken on phi(3770) the resonance with the CLEO-c detector. We find fD+ = (222.6 +/- 16.7(+2.8)(-3.4)) MeV, and compare with current theoretical calculations. We also set a 90% confidence upper limit on B(D+e+nu)< 2.4 x 10(-5) which constrains new physics models.     

Two-particle rapidity correlations in 205 GeV/c pp interactions

Using data obtained from an exposure of the 30-inch bubble chamber at NAL, inclusive and semi-inclusive two-particle rapidity correlations are analyzed for charged-charged, ??, ++, and ± particles. For the inclusive sample, positive correlations are observed in the central region. In the semi-inclusive case, the four-and six-prong events exhibit strong positive correlations near 90° CM. Selection of four-prong events with a large rapidity gap shows that the strong correlation seems to be associated with diffractive-type events.     

High-spin states in 90Nb

The high-spin states in ⁹⁰Nb have been studied by in-beam γ-ray spectroscopy using the 35 MeV ⁸⁹Y(α, 3nγ)⁹⁰Nb and 33 MeV ⁹⁰Zr(³He, p2nγ)⁹⁰Nb reactions. A new isomeric state with half-life 0.44±0.02 σs and J^π = 11^? has been located in this nucleus. The level scheme derived from these measurements is compared with shell-model calculations.