Non-Leptonic B Decays into K-Resonances

We estimate the non-leptonic B decays $B \rightarrow (\psi ,\psi^\prime , \chi_{1c})+K^i$, where $K^i$ are various K-meson resonances. We use the model of Isgur, Wise, Scora and Grinstein in the context of heavy quark effective theory, to calculate the hadronic matrix elements. Our estimates show that a substantial fraction of $B \rightarrow X_s \psi$ results in higher resonances of K-meson and besides $B \rightarrow K(K^*) \psi$, a considerable fraction of $B \rightarrow X_s (c\bar c)$ goes to $B \rightarrow (K,K^*)+( \psi^{\prime},\chi_{1c})$.Comment: 9 pages, late

Supersymmetric b→sγb \rightarrow s \gamma with Large Chargino Contributions

Supersymmetric (SUSY) theories are often thought to give large branching ratios for $b \rightarrow s \gamma$ from charged Higgs loops. We show that in many cases chargino loop contributions can cancel those of the Higgs, and SUSY can give $B(b \rightarrow s \gamma)$ at or below the \SM\ prediction. We show this occurs because the large stop mass splittings usually found in SUSY break a GIM mechanism suppression. These effects are strongly enhanced by large $\tan\beta$, so that $B(b \rightarrow s \gamma)$ is very sensitive to the value of $\tan\beta$, contrary to what has been claimed. We also note that the supergravity relation $B_0 = A_0-1$ is somewhat disfavored over the general case.Comment: TRI-PP-93-66. 12pp (Plain LATEX)+4 fig not incl. PostScript file of figs available (~3MB), contact Corrie Kost [email protected]. Request hardcopy or FAX of figures through [email protected]

The Concepts of Reliability and Homogeneity

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67956/2/10.1177_001316445001000103.pd

Prisoner's Dilemma cellular automata revisited: evolution of cooperation under environmental pressure

We propose an extension of the evolutionary Prisoner's Dilemma cellular automata, introduced by Nowak and May \cite{nm92}, in which the pressure of the environment is taken into account. This is implemented by requiring that individuals need to collect a minimum score $U_{min}$, representing indispensable resources (nutrients, energy, money, etc.) to prosper in this environment. So the agents, instead of evolving just by adopting the behaviour of the most successful neighbour (who got $U^{msn}$), also take into account if $U^{msn}$ is above or below the threshold $U_{min}$. If $U^{msn}<U_{min}$ an individual has a probability of adopting the opposite behaviour from the one used by its most successful neighbour. This modification allows the evolution of cooperation for payoffs for which defection was the rule (as it happens, for example, when the sucker's payoff is much worse than the punishment for mutual defection). We also analyse a more sophisticated version of this model in which the selective rule is supplemented with a "win-stay, lose-shift" criterion. The cluster structure is analyzed and, for this more complex version we found power-law scaling for a restricted region in the parameter space.Comment: 15 pages, 8 figures; added figures and revised tex

Using b→sγb \to s\gamma to Probe Top Quark Couplings

Possible anomalous couplings of the top-quark to on-shell photons and gluons are constrained by the recent results of the CLEO Collaboration on both inclusive and exclusive radiative $B$ decays. We find that the process \bsg\ can lead to reasonable bounds on both the anomalous electric and magnetic dipole moments of the top-quark, while essentially no limits are obtained on the corresponding chromoelectric and chromomagnetic moments, which enter the expression for the decay rate only through operator mixing.Comment: 10 pages plus 6 figures (available by request), LaTex, ANL-HEP-PR-93-3

Constraints on the R-parity- and Lepton-Flavor-Violating Couplings from B0 Decats to Two Charged Leptons

We derive the upper bounds on certain products of R-parity- and lepton-flavor-violating couplings from the decays of the neutral $B$ meson into two charged leptons. These modes of $B^0$ decays can constrain the product combinations of the couplings with one or more heavy generation indices. We find that most of these bounds are stronger than the previous ones.Comment: Table is changed; version to appear in Phys. Rev.

Recalculation of QCD Corrections to b→sγb \to s \gamma Decay

We give a more complete calculation of $b \to s\gamma$ decay, including leading log QCD corrections from $m_{top}$ to $M_W$ in addition to corrections from $M_{W}$ to $m_b$. We have included the full set of dimension-6 operators and corrected numerical mistakes of anomalous dimensions in a previous paper\cite{Cho}. Comparing with the calculations without QCD running from $m_{top}$ to $M_W$\cite{Mis}, the inclusive decay rate is found to be enhanced. At $m_t=150$GeV, it results in 12\% enhancement, and for $m_t=250$GeV, 15\% is found. The total QCD effect makes an enhanced factor of 4.2 at $m_t=150$GeV, and 3.2 for $m_t=250$GeV.Comment: 16 pages, 7 figures (uuencoded ps files), Changes of description. To appear in Phys. Rev.

Turbulence driven by outflow-blown cavities in the molecular cloud of NGC 1333

Outflows from young stellar objects have been identified as a possible source of turbulence in molecular clouds. To investigate the relationship between outflows, cloud dynamics and turbulence, we compare the kinematics of the molecular gas associated with NGC 1333, traced in 13CO(1-0), with the distribution of young stellar objects (YSOs) within. We find a velocity dispersion of ~ 1-1.6 km/s in 13CO that does not significantly vary across the cloud, and is uncorrelated with the number of nearby young stellar outflows identified from optical and submillimeter observations. However, from velocity channel maps we identify about 20 cavities or depressions in the 13CO intensity of scales > 0.1-0.2 pc and velocity widths 1-3 km/s. The cavities exhibit limb brightened rims in both individual velocity channel maps and position velocity diagrams, suggesting that they are slowly expanding. We interpret these cavities to be remnants of past YSO outflow activity: If these cavities are presently empty, they would fill in on time scales of a million years. This can exceed the lifetime of a YSO outflow phase, or the transit time of the central star through the cavity, explaining the the absence of any clear correlation between the cavities and YSO outflows. We find that the momentum and energy deposition associated with the expansion of the cavities is sufficient to power the turbulence in the cloud. In this way we conclude that the cavities are an important intermediary step between the conversion of YSO outflow energy and momentum into cloud turbulent motions.Comment: Accepted for publication in ApJ. Check out http://astro.pas.rochester.edu/~aquillen/coolpics.html for channel map and PosVel movies of N133

The Assessment of Reliability Under Range Restriction: A Comparison of α, ω, and Test–Retest Reliability for Dichotomous Data

Though much research and attention has been directed at assessing the correlation coefficient under range restriction, the assessment of reliability under range restriction has been largely ignored. This article uses item response theory to simulate dichotomous item-level data to assess the robustness of KR-20 (α), ω, and test–retest under varying selection ratios. These estimators, both corrected and uncorrected for range restriction, were compared in terms of both bias and precision. Test–retest reliability was usually the best estimator of reliability across a variety of conditions. Only under indirect range restriction did KR-20 and ω performed well. All estimators suffered imprecision as a function of range restriction, above and beyond the reduction in sample size. Based on the results, a set of recommendations are proposed.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline