Search for TeV Scale Physics in Heavy Flavour Decays

The subject of heavy flavour decays as probes for physics beyond the TeV scale is covered from the experimental perspective. Emphasis is placed on the more traditional Beyond the Standard Model topics that have potential for impact in the short term, with the physics explained. We do unabashedly promote our own phemonenology work.Comment: 10 pages, 9 figures (now fixed); Submitted for the SUSY07 proceeding

Direct CP Violation, Branching Ratios and Form Factors B→πB \to \pi, B→KB \to K in BB Decays

The $B \to \pi$ and $B \to K$ transitions involved in hadronic B decays are investigated in a phenomenological way through the framework of QCD factorization. By comparing our results with experimental branching ratios from the BELLE, BABAR and CLEO Collaborations for all the B decays including either a pion or a kaon, we propose boundaries for the transition form factors $B \to \pi$ and $B \to K$ depending on the CKM matrix element parameters $\rho$ and $\eta$. From this analysis, the form factors required to reproduce the experimental data for branching ratios are $F^{B \to \pi}= 0.31 \pm 0.12$ and $F^{B \to K}= 0.37\pm 0.13$. We calculate the direct CP violating asymmetry parameter, $a_{CP}$, for $B \to \pi^{+} \pi^{-} \pi$ and $B \to \pi^{+} \pi^{-} K$ decays, in the case where $\rho-\omega$ mixing effects are taken into account. Based on these results, we find that the direct CP asymmetry for $B^{-} \to \pi^{+} \pi^{-} \pi^{-}$, $\bar{B}^{0} \to \pi^{+} \pi^{-} \pi^{0}$, $B^{-} \to \pi^{+} \pi^{-} K^{-}$, and $\bar{B}^{0} \to \pi^{+} \pi^{-} \bar{K}^{0}$, reaches its maximum when the invariant mass $\pi^{+} \pi^{-}$ is in the vicinity of the $\omega$ meson mass. The inclusion of $\rho-\omega$ mixing provides an opportunity to erase, without ambiguity, the phase uncertainty mod$(\pi)$ in the determination of the CKM angles $\alpha$ in case of $b\to u$ and $\gamma$ in case of $b \to s$.Comment: 74 pages, 15 figures, 8 tables. A few misprints corrected, two references adde

Study of D_(sJ) decays to D*K in inclusive e^+e^- interactions

We observe the decays D*_(s1)(2710)^+ → D*K and D*_(sJ)(2860)^+ → D*K and measure their branching fractions relative to the DK final state. We also observe, in the D*K mass spectrum, a new broad structure at a mass of (3044 ± 8_(stat)(^(+30)_(-5))_(syst))  MeV/c^2 having a width Γ =(239 ± 35_(stat)(^(+46)_(-42))_(syst))  MeV. To obtain this result we use 470  fb^(-1) of data recorded by the BABAR detector at the PEP-II asymmetric-energy e^+e^- storage rings at the Stanford Linear Accelerator Center running at center-of-mass energies near 10.6 GeV

Measurement of branching fractions of B decays to K_1(1270)π and K_1(1400)π and determination of the CKM angle α from B^0→a_1(1260)^±π^∓

We report measurements of the branching fractions of neutral and charged B meson decays to final states containing a K_1(1270) or K_1(1400) meson and a charged pion. The data, collected with the BABAR detector at the SLAC National Accelerator Laboratory, correspond to 454×10^6 BB̅ pairs produced in e^+e^- annihilation. We measure the branching fractions B(B^0→K_1(1270)^+π-+K_1(1400)^+π-)=3.1_(-0.7)^(+0.8)×10^(-5) and B(B^+→K_1(1270)^0π^++K_1(1400)^0π^+)=2.9_(-1.7)^(+2.9)×10^(-5) (<8.2×10^(-5) at 90% confidence level), where the errors are statistical and systematic combined. The B^0 decay mode is observed with a significance of 7.5σ, while a significance of 3.2σ is obtained for the B^+ decay mode. Based on these results, we estimate the weak phase α=(79±7±11)° from the time-dependent CP asymmetries in B^0→a1(1260)^±π^∓ decays

Measurements of the τ mass and the mass difference of the τ^+ and τ^- at BABAR

We present the result from a precision measurement of the mass of the τ lepton, M_τ, based on 423  fb^(-1) of data recorded at the Υ(4S) resonance with the BABAR detector. Using a pseudomass endpoint method, we determine the mass to be 1776.68±0.12(stat)±0.41(syst)  MeV. We also measure the mass difference between the τ^+ and τ^-, and obtain (M_(τ+)-M_(τ-))/M_(AVG)^τ=(-3.4±1.3(stat)±0.3(syst))×10^(-4), where M^τ_(AVG) is the average value of M_(τ+) and M_(τ-)

Search for B^+→ℓ^+ν_ℓ recoiling against B^-→D^0ℓ^-ν̅ X

We present a search for the decay B^+→ℓ^+ν_ℓ(ℓ=τ, μ, or  e) in (458.9±5.1)×10^6 BB̅ pairs recorded with the BABAR detector at the PEP-II B-factory. We search for these B decays in a sample of B^+B^- events where one B-meson is reconstructed as B^-→D^0ℓ^-ν̅ X. Using the method of Feldman and Cousins, we obtain B(B^+→τ^+ν_τ)=(1.7±0.8±0.2)×10^(-4), which excludes zero at 2.3σ. We interpret the central value in the context of the standard model and find the B meson decay constant to be f_B^2=(62±31)×10^3   MeV^2. We find no evidence for B^+→e^+ν_e and B^+→μ^+ν_μ and set upper limits at the 90% C.L. B(B^+→e^+ν_e)<0.8×10^(-5) and B(B^+→μ^+ν_μ)<1.1×10^(-5)

Observation of the χ_(c2)(2P) meson in the reaction γγ→DD at BABAR

A search for the Z(3930) resonance in γγ production of the DD system has been performed using a data sample corresponding to an integrated luminosity of 384  fb^(-1) recorded by the BABAR experiment at the PEP-II asymmetric-energy electron-positron collider. The DD invariant mass distribution shows clear evidence of the Z(3930) state with a significance of 5.8σ. We determine mass and width values of (3926.7±2.7±1.1)  MeV/c^2 and (21.3±6.8±3.6)  MeV, respectively. A decay angular analysis provides evidence that the Z(3930) is a tensor state with positive parity and C parity (J^(PC)=2^(++)); therefore we identify the Z(3930) state as the χ_(c2)(2P) meson. The value of the partial width Γ_(γγ)×B(Z(3930)→DD) is found to be (0.24±0.05±0.04)  keV

Synthesis and photophysical characteristics of polyfluorene polyrotaxanes

Two alternating polyfluorene polyrotaxanes (3·TM-βCD and 3·TM-γCD) have been synthesized by the coupling of 2,7-dibromofluorene encapsulated into 2,3,6-tri-O-methyl-β- or γ-cyclodextrin (TM-βCD, TM-γCD) cavities with 9,9-dioctylfluorene-2,7-diboronic acid bis(1,3-propanediol) ester. Their optical, electrochemical and morphological properties have been evaluated and compared to those of the non-rotaxane counterpart 3. The influence of TM-βCD or TM-γCD encapsulation on the thermal stability, solubility in common organic solvents, film forming ability was also investigated. Polyrotaxane 3·TM-βCD exhibits a hypsochromic shift, while 3·TM-γCD displays a bathochromic with respect to the non-rotaxane 3 counterpart. For the diluted CHCl3 solutions the fluorescence lifetimes of all compounds follow a mono-exponential decay with a time constant of ≈0.6 ns. At higher concentration the fluorescence decay remains mono-exponential for 3·TM-βCD and polymers 3, with a lifetime τ = 0.7 ns and 0.8 ns, whereas the 3·TM-γCD polyrotaxane shows a bi-exponential decay consisting of a main component (with a weight of 98% of the total luminescence) with a relatively short decay constant of τ1 = 0.7 ns and a minor component with a longer lifetime of τ2 = 5.4 ns (2%). The electrochemical band gap (ΔEg) of 3·TM-βCD polyrotaxane is smaller than that of 3·TM-γCD and 3, respectively. The lower ΔEg value for 3·TM-βCD suggests that the encapsulation has a greater effect on the reduction process, which affects the LUMO energy level value. Based on AFM analysis, 3·TM-βCD and 3·TM-γCD polyrotaxane compounds exhibit a granular morphology with lower dispersity and smaller roughness exponent of the film surfaces in comparison with those of the neat copolymer 3

Observation and polarization measurement of B^0 → a_1(1260)^(+)a_1(1260)^(-) decay

We present measurements of the branching fraction B and longitudinal polarization fraction f_L for B^0 → a_1(1260)^(+)a_1(1260)^(-) decays, with a_1(1260)^(±) → π^(-)π^(+)π^(±). The data sample, collected with the BABAR detector at the SLAC National Accelerator Laboratory, represents 465 × 10^6 produced BB(overbar) pairs. We measure B(B^0 → a_1(1260)^(+)a_1(1260)^-) × [B(a_1(1260)^+ → π^(-)π^(+)π^(+))]^2 = (11.8±2.6±1.6) ×10^(-6) and f_L = 0.31±0.22±0.10, where the first uncertainty is statistical and the second systematic. The decay mode is measured with a significance of 5.0 standard deviations including systematic uncertainties