Light sigma-Meson Production in Excited Upsilon Decay Processes I: Analyses

We analyze the pi pi production amplitudes in the excited Upsilon decay processes, Upsilon(2S)-->Upsilon(1S)pi+pi-, Upsilon(3S)-->Upsilon(1S)pi+pi- and Upsilon(3S)-->Upsilon(2S)pi+pi-, and the pi pi and KKbar production amplitudes in the charmonium decay processes, psi(2S)-->J psi pi+pi- and J psi-->phi pi+pi-, phi K+K-. The amplitudes are parametrized by the sum of Breit-Wigner amplitudes for the sigma and the other relevant particles and of the direct 2pi-production amplitude, following the VMW method. All the pi pi (and KKbar) invariant mass spectra are reproduced well with the sigma Breit-Wigner amplitude by using the common parameters, m_sigma=526^(+48)_(-37) MeV and Gamma_sigma =301^(+145)_(-100) MeV, which is almost consistent with the values obtained in our previous phase shift analyses. This strongly suggests the existence of light sigma-meson.Comment: proc. of ``Possible Existence of sigma-Meson and Its Implication to Hadron Physics," YITP, Kyoto, June 12--14, 2000. 5 pages, uses ptptex.st

Multipole Amplitudes of Pion Photoproduction on Nucleons up to 2GeV within Dispersion Relations and Unitary Isobar Model

Two approaches for analysis of pion photo- and electroproduction on nucleons in the resonance energy region are checked at $Q^2=0$ using the results of GWU(VPI) partial-wave analysis of photoproduction data. The approaches are based on dispersion relations and unitary isobar model. Within dispersion relations good description of photoproduction multipoles is obtained up to $W=1.8 GeV$. Within unitary isobar model, modified with increasing energy by incorporation of Regge poles, and with unified Breit-Wigner parametrization of resonance contributions, good description of photoproduction multipoles is obtained up to $W=2 GeV$.Comment: 23 pages, LaTe

Strong Λπ\Lambda \pi Phase Shifts for CP Violation in Weak Ξ→Λπ\Xi \rightarrow \Lambda \pi Decay

Strong interaction $\Lambda\pi$ phase shifts relevant for the weak nonleptonic decay $\Xi \rightarrow \Lambda \pi$ are calculated using baryon chiral perturbation theory. We find in leading order that the S-wave phase shift vanishes and the $J={1 \over 2}$ P-wave phase shift is $-1.7 ^{\rm o}$. The small phase shifts imply that CP violation in this decay will be difficult to observe. Our results follow from chiral $SU(2)_L\times SU(2)_R$ symmetry.Comment: 8 pages, uses phyzzx, 2 figures included as uuencoded file, CALT-68-1940 and CMU-HEP94-2

Effects of adjunctive eslicarbazepine acetate on serum lipids in patients with partial-onset seizures: Impact of concomitant statins and enzyme-inducing antiepileptic drugs.

PURPOSE: To evaluate the effects of eslicarbazepine acetate (ESL) on lipid metabolism and to determine whether reduced statin exposure during ESL therapy has clinical consequences. SUBJECTS AND METHODS: We conducted a post-hoc analysis of pooled data for serum lipids (laboratory values) from three phase III, multicenter, randomized, double-blind, placebo-controlled trials of adjunctive ESL therapy (400, 800, or 1200 mg once daily) in patients with treatment-refractory partial-onset seizures. Changes from baseline in serum lipid levels were analyzed according to use of statins and/or enzyme-inducing antiepileptic drugs (EIAEDs) during the baseline period. KEY FINDINGS: In total, 426 and 1021 placebo- and ESL-treated patients, respectively, were included in the analysis. With regard to the changes from baseline in serum concentrations, there were statistically significant differences between the placebo and ESL 1200 mg QD groups, for both total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C), but the effect sizes were small (+4.1 mg/dL and +1.8 mg/dL, respectively). A small but significant difference in low-density lipoprotein cholesterol (LDL-C; -5.0 mg/dL) was observed between the ESL 400 mg QD group and the placebo group. In patients not taking a concomitant EIAED, there were no changes with ESL 400 mg QD, but modest and statistically significant increases in cholesterol fractions (TC, LDL-C and HDL-C) with ESL 800 mg QD (/dL) and ESL 1200 mg QD (/dL). ESL had no consistent effect on lipids in patients taking a concomitant EIAED. In patients taking statins during baseline, there were no clinically relevant changes in serum lipids during use of ESL, although the subgroups were small. SIGNIFICANCE: These results suggest that ESL does not appear to have clinically significant effects on serum lipids, nor does the pharmacokinetic interaction between ESL and statins have an impact on serum lipid concentrations

On nature of scalar a_0(980) and f_0(980)-mesons

It is presented a critical consideration of all unusual properties of the scalar a_0(980) and f_0(980)-mesons in the four-quark, two-quark and molecular models. The arguments are adduced that the four-quark model is more preferable. It is discussed the complex of experiments that could finally resolve this issue.Comment: 6 pages, LaTeX 2e, uses espcrc1.sty, Plenary Talk given at 8th International Conference on HADRON Spectroscopy (HADRON 99), Beijing, China, 24-28 August 199

Search for the Lepton-Number-Violating Decay Ξ−→pμ−μ−\Xi^- \to p \mu^- \mu^-

A sensitive search for the lepton-number-violating decay $\Xi^-\to p \mu^-\mu^-$ has been performed using a sample of $\sim10^9$ $\Xi^-$ hyperons produced in 800 GeV/$c$ $p$-Cu collisions. We obtain $\mathcal{B}(\Xi^-\to p \mu^-\mu^-)< 4.0\times 10^{-8}$ at 90% confidence, improving on the best previous limit by four orders of magnitude.Comment: 9 pages, 5 figures, to be published in Phys. Rev. Let

Listening for Place, Marketing Identity: Latin American Composers of New Music in the U.S.

Latin American Studie

TWO PHOTON PHYSICS WITH THE MARK II AT PEP

Measurements of the mass spectrum and angular distribution of high mass meson pairs produced in ..gamma gamma.. interactions are compared with QCD predictions. The radiative width (GAMMA(eta' ..-->.. ..gamma gamma..) is measured using three different eta' decay modes. Upper limits for the iota radiative width are given

Ossianic Telegraphy: Bardic Networks and Imperial Relays

Relates James Macpherson\u27s Fragments of Ancient Poetry (1760) and other Ossianic poems to evolving Scottish networks of commerce and communication, especially commercial telegraphy and the postal system, and posits associations also with comments in Adam Smith\u27s Lectures on Jurisprudence and Theory of Moral Sentiments, to suggest that Macpherson\u27s remediation of oral poetry asserted ideas of authorial identity and readership as relays in a new imperial network

delta S = 2 nonleptonic hyperon decays

A sensitive search for the rare decays \Omega^- \to \Lambda \pi^- and \Xi^0 \to p \pi^- has been performed using data from the 1997 run of the HyperCP (Fermilab E871) experiment. Limits on other such processes do not exclude the possibility of observable rates for |\Delta S| = 2 nonleptonic hyperon decays, provided the decays occur through parity-odd operators. We obtain the branching-fraction limits B(\Omega^- \to \Lambda \pi^-)< 2.9 x 10^{-6} and B(\Xi^0 \to p \pi^-)< 8.2 x 10^{-6}, both at 90% confidence level.Comment: 4 pages, 5 figures, PRL pape