Collins asymmetries in inclusive charged KK and Kπ pairs produced in e+e- annihilation.

We present measurements of Collins asymmetries in the inclusive process e+e-→h1h2X, h1h2=KK, Kπ, ππ, at the center-of-mass energy of 10.6 GeV, using a data sample of 468 fb-1 collected by the BABAR experiment at the PEP-II B factory at SLAC National Accelerator Center. Considering hadrons in opposite thrust hemispheres of hadronic events, we observe clear azimuthal asymmetries in the ratio of unlike sign to like sign, and unlike sign to all charged h1h2 pairs, which increase with hadron energies. The Kπ asymmetries are similar to those measured for the ππ pairs, whereas those measured for high-energy KK pairs are, in general, larger

Search for a light Higgs resonance in radiative decays of the (1S) with a charm tag

A search is presented for the decay (1S)→γA0, A0→cc¯, where A0 is a candidate for the CP-odd Higgs boson of the next-to-minimal supersymmetric standard model. The search is based on data collected with the BABAR detector at the (2S) resonance. A sample of (1S) mesons is selected via the decay (2S)→π+π-(1S). The A0→cc¯ decay is identified through the reconstruction of hadronic D0, D+, and D∗(2010)+ meson decays. No significant signal is observed. The measured 90% confidence-level upper limits on the product branching fraction B((1S)→γA0)×B(A0→cc¯) range from 7.4×10-5 to 2.4×10-3 for A0 masses from 4.00 to 8.95GeV/c2 and 9.10 to 9.25GeV/c2, where the region between 8.95 and 9.10GeV/c2 is excluded because of background from (2S)→γχbJ(1P), χbJ(1P)→γ(1S) decays

Measurements of the B -> D-* form factors using the decay (B)over-bar(0)-> D(*+)e(-)(v)over-bar(e)

We measure the dependence of (B) over bar (0)-> D(*+)e(-)(B) over bar (e) on the decay angles and momentum transfer. The data sample consists of similar to 86x10(6) B (B) over bar -pairs accumulated on the Upsilon(4S) resonance by the BABAR detector at the asymmetric e(+)e(-) collider PEP-II. We specify the three form factors by two ratios R-1 and R-2, and by a single parameter rho(2) characterizing the polynomial representing h(A1), the function which describes the momentum-transfer dependence of the form factor A(1). We determine R-1, R-2, and rho(2) using an unbinned maximum likelihood fit to the full decay distribution. The results are R-1=1.396 +/- 0.060 +/- 0.035 +/- 0.027, R-2=0.885 +/- 0.040 +/- 0.022 +/- 0.013, and rho(2)=1.145 +/- 0.059 +/- 0.030 +/- 0.035. The stated uncertainties are the statistical from the data, statistical from the size of the Monte Carlo sample and the systematic uncertainty, respectively. In addition, based on this measurement, we give an updated value for the CKM matrix element vertical bar V-cb vertical bar

Observation of B→D(*) π+π−ℓ−νbar Decays in e+e- Collisions at the Υ(4S) Resonance

We report on measurements of the decays of Bbar mesons into the semileptonic final states Bbar-->D(*)pi+pi-l-nubar, where D(*) represents a D or D* meson and l- is an electron or a muon. These measurements are based on 471x10^6 BBbar pairs recorded with the BABAR detector at the SLAC asymmetric B factory PEP-II. We determine the branching fraction ratios R_pi+pi-(*)=B(Bbar-->D(*)pi+pi-l-nubar)/B(Bbar-->D(*)l-nubar) using events in which the second B meson is fully reconstructed. We find Rpi+pi-=0.067±0.010±0.008 and Rpi+pi-=0.019±0.005±0.004, where the first uncertainty is statistical and the second is systematic. Based on these results and assuming isospin invariance, we estimate that Bbar-->D(*)pipil-nubar decays, where pi denotes either a pi± and pi0 meson, account for up to half the difference between the measured inclusive semileptonic branching fraction to charm hadrons and the corresponding sum of previously measured exclusive branching fractions

Measurement of the Branching Fractions of (B)over-bar -> D**l(-)(v)over-bar(l) Decays in Events Tagged by a Fully Reconstructed B Meson

We report a measurement of the branching fractions of B -> D**l(-)(v) over bar (l) decays based on 417 fb(-1) of data collected at the Y(4S) resonance with the BABAR detector at the PEP-II e(+) e(-) storage rings. Events are selected by fully reconstructing one of the B mesons in a hadronic decay mode. A fit to the invariant mass differences m(D-(*())pi) - (m(D-(*())) is performed to extract the signal yields of the different D** states. We observe the (B) over bar -> D**l(-)(v) over bar (l) decay modes corresponding to the four D** states predicted by heavy quark symmetry with a significance greater than 5 standard deviations including systematic uncertainties

Measurement of the γγ*→π0 transition form factor

We study the reaction e + e − → e + e − π 0 in the single tag mode and measure the differential cross section d σ / d Q 2 and the γ γ ∗ → π 0 transition form factor in the momentum transfer range from 4 to 40     GeV 2 . At Q 2 > 10     GeV 2 the measured form factor exceeds the asymptotic limit predicted by perturbative QCD. The analysis is based on 442     fb − 1 of integrated luminosity collected at PEP-II with the BABAR detector at e + e − center-of-mass energies near 10.6 GeV

Unsaturated σ-hydrocarbyl transition-metal complexes. Part 2. Synthesis and reactions of vinylplatinum complexes and a comparison with analogous fluorovinyl and alkynyl complexes

Alkenyl (CHCH2 or CFCF2) or alkynyl (CCPh) derivatives of trimethyltin are shown to be superior to lithium or magnesium reagents for the synthesis of corresponding mono-organoplatinum(II) species by metathesis (L = SnMe3R +cis-[PtCl2L2]→trans-[PtRClL2]+ SnMe3Cl tertiary phosphine). The reactivity order for SnMe3R is R = CCPh > CFCF2 > CHCH2. This order is also found for oxidative addition of SnMe3R to Pt0 to give cis-[PtRL2(SnMe3)]. When the latter complex (R = CHCH2) reacts with X2 or MeX further oxidative addition occurs exclusively at the platinum centre. Aromatic isonitriles (R′NC)co-ordinate to the platinum and give insertion products trans-[Pt{C(CHCH2)= NR′}ClL2] on heating or carbene complexes with NBunH2. The alkynyl trans-[Pt(CCPh)ClL2] also forms 1 :1 adducts with R′NC and carbene complexes therefrom, but no insertion products. Spectroscopic data for the new complexes are presented

Dalitz plot analyses of B-0 -> (D-DK+)-K-0 and B+-> (D)over-bar(-)D(0)K(+) decays

We present Dalitz plot analyses for the decays of B mesons to D−D0K+ and D¯0D0K+. We report the observation of the D∗s1(2700)+ resonance in these two channels and obtain measurements of the mass M(D∗s1(2700)+)=2699+14−7  MeV/c2 and of the width Γ(D∗s1(2700)+)=127+24−19  MeV, including statistical and systematic uncertainties. In addition, we observe an enhancement in the D0K+ invariant mass around 2350–2500  MeV/c2 in both decays B0→D−D0K+ and B+→D¯0D0K+, which we are not able to interpret. The results are based on 429  fb−1 of data containing 471×106BB¯ pairs collected at the ϒ(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory

Search for Long-Lived Particles in e(+)e(-) Collisions

We present a search for a neutral, long-lived particle L that is produced in e+e− collisions and decays at a significant distance from the e+e− interaction point into various flavor combinations of two oppositely charged tracks. The analysis uses an e+e− data sample with a luminosity of 489.1  fb−1 collected by the BABAR detector at the ϒ(4S), ϒ(3S), and ϒ(2S) resonances and just below the ϒ(4S). Fitting the two-track mass distribution in search of a signal peak, we do not observe a significant signal, and set 90% confidence level upper limits on the product of the L production cross section, branching fraction, and reconstruction efficiency for six possible two-body L decay modes as a function of the L mass. The efficiency is given for each final state as a function of the mass, lifetime, and transverse momentum of the candidate, allowing application of the upper limits to any production model. In addition, upper limits are provided on the branching fraction ℬ(B→XsL), where Xs is a strange hadronic system

Exclusive production of D_{s}^{+}D_{s}^{-}, D_{s}^{*+}D_{s}^{-}, and D_{s}^{*+}D_{s}^{*-} via e^{+}e^{-} annihilation with initial-state radiation

We perform a study of exclusive production of Ds+Ds-, Ds*+Ds-, and Ds*+Ds*- final states in initial-state-radiation events from e+e- annihilations at a center-of-mass energy near 10.58 GeV, to search for charmonium 1-- states. The data sample corresponds to an integrated luminosity of 525  fb-1 and was recorded by the BABAR experiment at the PEP-II storage ring. The Ds+Ds-, Ds*+Ds-, and Ds*+Ds*- mass spectra show evidence of the known ψ resonances. Limits are extracted for the branching ratios of the decays X(4260)→Ds(*)+Ds(*)-