Two body decays of the bb-quark: Applications to direct CP violation, searches for electro-weak penguins and new physics

A systematic experimental search for two-body hadronic decays of the b-quark of the type b to quark + meson is proposed. These reactions have a well defined experimental signature and they should be theoretically cleaner compared to exclusive decays. Many modes have appreciable branching ratios and partial rate asymmetries may also be quite large (about 8-50%) in several of them. In a few cases electroweak penguins appear to be dominant and may be measurable. CP violating triple correlation asymmetries provide a clean test of the Standard Model.Comment: 12 pages 1 figure 1 tabl

Obtaining CKM Phase Information from B Penguin Decays

We discuss a method for extracting CP phases from pairs of B decays which are related by flavor SU(3). One decay (B0 -> M1 M2) receives a significant bbar -> dbar penguin contribution. The second (B' -> M1' M2') has a significant bbar -> sbar penguin contribution, but is dominated by a single amplitude. CP phase information is obtained using the fact that the B' -> M1' M2' amplitude is related by SU(3) to a piece of the B0 -> M1 M2 amplitude. The leading-order SU(3)-breaking effect (~25%) responsible for the main theoretical error can be removed. For some decay pairs, it can be written in terms of known decay constants. In other cases, it involves a ratio of form factors. However, this form-factor ratio can either be measured experimentally, or eliminated by considering a double ratio of amplitudes. In all cases, one is left only with a second-order effect, ~5%. We find twelve pairs of B decays to which this method can be applied. Depending on the decay pair, we estimate the total theoretical error in relating the B' -> M1' M2' and B0 -> M1 M2 amplitudes to be between 5% and 15%. The most promising decay pairs are Bd -> pi+ pi- and Bu+ -> K0 pi+, and Bd -> D+ D- and Bd -> Ds+ D- or Bu+ -> Ds+ D0bar.Comment: 38 pages, JHEP format, no figures. Comments added to text regarding most promising decay pairs; references added; conclusions unchange

Extracting information on CKM phases, electro-weak penguins and new physics from B --> VV decays

We derive constraints for $B\to VV$ modes ($V= vector meson) that allow aquantitative assessment of the contributions from electroweak penguins (EWP) and/or new physics. Interplay of direct CP with oscillation studies then leads to the extraction of the angles alpha and gamma, using B--> K* omega rho and B--> rho omega (phi) respectively, if by using our constraint equations it can be experimentally demonstrated that color-suppressed EWP are small.Comment: 12 pages, 0 figures; revised and expande

The Possibility of Large Direct CP Violation in B to K pi-Like Modes Due to Long Distance Rescattering Effects and Implications for the Angle gamma

We consider the strong rescattering effects that can occur in the decays such as B -> K pi, K* pi, K rho... and their impact on direct CP violation in these modes. First we discuss, in general, how the CPT theorem constrains the resulting pattern of partial rate asymmetries leading to different brands of direct CP. Traditional discussions have centered around the absorptive part of the penguin graph which has Delta I=0 in b -> s transitions and as a result causes ``simple'' CP violation; long-distance final state rescattering effects, in general, will lead to a different pattern of CP: ``compound'' CP violation. Predictions of simple CP are quite distinct from that of compound CP. Final states rescattering phases in B decays are unlikely to be small possibly causing large compound CP violating partial rate asymmetries in these modes. CPT theorem requires a cancellation of PRA due to compound CP amongst the $K\pi$ states themselves; thus there can be no net cancellation with other states such as K*\pi, K\rho etc. Therefore, each class of such modes, namely K pi, K rho, K^*pi, K a_1 etc. can have large direct CP emanating from rescattering effects. Various repercussions for the angle $\gamma$ are also discussed.Comment: 45 pages; 5 figures. In replacement we have : 1) corrected many typos, 2) added references, 3) decided to subdivide Simple CP into 2 categories and 4) Modified figure 3 to explain tha

ELECTROWEAK PENGUINS AND TWO-BODY B DECAYS

We discuss the role of electroweak penguins in $B$ decays to two light pseudoscalar mesons. We confirm that the extraction of the weak phase $\alpha$ through the isospin analysis involving $B\to\pi\pi$ decays is largely unaffected by such operators. However, the methods proposed to obtain weak and strong phases by relating $B\to\pi\pi$, $B\to\pi K$ and $B\to KK$ decays through flavor SU(3) will be invalidated if electroweak penguins are large. We show that, although the introduction of electroweak penguin contributions introduces no new amplitudes of flavor SU(3), there are a number of ways to experimentally measure the size of such effects. Finally, using SU(3) amplitude relations we present a new way of measuring the weak angle $\gamma$ which holds even in the presence of electroweak penguins.Comment: 18 pages, 3 figures, LaTeX file. The full postscript manuscript is available by anonymous ftp at ftp://lpsvsh.lps.umontreal.ca/theorie/hep-ph/EWpenguins.ps (a VAX so use the format theorie.hep-ph if you change by more than one directory at a time

Current Options for the Treatment of Food Allergy

Food allergy is increasing in prevalence; as a result, there is intense focus on developing safe and effective therapies. Current methods of specific immunotherapy include oral, sublingual, and epicutaneous, while nonspecific methods that have been investigated include: Chinese herbal medicine, probiotics, and anti-IgE antibodies. Although some studies have demonstrated efficacy in inducing desensitization, questions regarding safety and the potential for achieving immune tolerance remain. Although some of these therapies demonstrate promise, further investigation is required before their incorporation into routine clinical practice

Long-term treatment with egg oral immunotherapy enhances sustained unresponsiveness that persists after cessation of therapy

We previously reported results of a randomized, placebo-controlled study of egg oral immunotherapy (eOIT), in which 27.5% of subjects achieved sustained unresponsiveness (SU) after 2 years. Here we report results of treatment through 4 years and long-term follow-up