Prospects for Pentaquark Searches in e+e−e^+e^- Annihilations and γγ\gamma\gamma Collisions

Recent strong experimental evidence of a narrow exotic S = +1 baryon resonance, $\Theta^+$, suggests the existence of other exotic baryons. We discuss the prospects of confirming earlier experimental evidence of $\Theta^+$ and the observation of additional hypothetical exotic baryons in $e^+e^-$ annihilations and $\gamma\gamma$ collisions at LEP and B Factories

Top Production in Hadron-Hadron Collisions and Anomalous Top-Gluon Couplings

We discuss the influence of anomalous tbar-t-G couplings on total and differential tbar-t production cross sections in hadron-hadron collisions. We study in detail the effects of a chromoelectric and a chromomagnetic dipole moment, d' and \mu', of the top quark. In the d'-\mu' plane, we find a whole region where the anomalous couplings give a zero net contribution to the total top production rate. In differential cross sections, the anomalous moments have to be quite sizable to give measurable effects. We estimate the values of d' and \mu' which are allowed by the present Tevatron experimental results on top production. A chromoelectric dipole moment of the top violates CP invariance. We discuss a simple CP-odd observable which allows for a direct search for CP violation in top production.Comment: footnote pg. 4 changed, acknowledgments extende

Correlated inclusive /\bar production in e+e- annihilations at sqrt(s)~10.5 GeV

Using a 13.7/fb sample of continuum two-jet e+e- -> qqbar events collected with the CLEO detector, we have searched for correlations between / and /\bar particles, specifically in cases where the opening angle between the two particles is large and each has momentum $>$1 GeV/c. Such correlations may indicate the presence of baryon number conservation at the primary quark level. A previous CLEO study of /\c/\cbar correlations indicated direct, associated production of primary charmed baryons /\c: e+e- -> ccbar -> /\c/\cbar. That effect was not observed in Monte Carlo simulations. Our current search for similar direct, associated production of / baryons at the primary quark level (e+e- -> ssbar -> /\bar, e.g.) qualitatively indicates a similar effect, although it relies on a Monte Carlo dependent subtraction of background /\bar production (based on the default JETSET 7.4 event generator)

Measurements of Charm Fragmentation into Ds∗+D_s^{*+} and Ds+D_s^+ in e+e−e^+e^- Annihilations at s\sqrt{s}=10.5 GeV

A study of charm fragmentation into $D_s^{*+}$ and $D_s^+$ in $e^+e^-$ annihilations at $\sqrt{s}$=10.5 GeV is presented. This study using $4.72 \pm 0.05$ fb$^{-1}$ of CLEO II data reports measurements of the cross-sections $\sigma(D_s^{*+})$ and $\sigma(D_s^+)$ in momentum regions above $x=0.44$, where $x$ is the $D_s$ momentum divided by the maximum kinematically allowed $D_s$ momentum. The $D_s$ vector to vector plus pseudoscalar production ratio is measured to be $P_V(x(D_s^+)>0.44)=0.44\pm0.04$Comment: 21 pages, 6 figure