116899288
Inclusive Hadronic Results at BaBar: ISR and Pentaquark Searches
We present recent measurements of hadronic cross-sections from the BaBar experiment and report preliminary results on searches for pentaquark states. Studies of hadronic cross-sections using initial-state radiation offer promising prospects at BaBar. Many exclusive channels have already been measured, and more are in progress. A fully inclusive analysis should also offer a precise measurement of {Delta}{alpha}{sub QED}{sup Had}. Searches for pentaquark states have so far been negative, but they have served to highlight the potential for the study of charmed and non-charmed baryons at high-luminosity e{sup +}e{sup -} colliders.
118951342
Studies of e+e− Collisions with a Hard Initial‐State Photon at BaBar
We present preliminary BaBar measurements of hadronic cross sections in e+e- annihilation using the radiative return technique. The cross sections for e+e- {yields} pp-bar, 3({pi}+{pi}-), 2({pi}+{pi}-)2{pi}0, and K+K-2({pi}+{pi}-) are measured. Measurements of the proton form factor and of the ratio GE/GM are also shown.
104344849
Measurement of the CP-violating asymmetries in $B^0 \to K^0_{S} \pi^0$ and of the branching fraction of $B^0 \to K^0 \pi^0$
117483857
Search for quark contact interactions in dijet angular distributions in pp collisions at s=7 TeV measured with the ATLAS detector
Dijet angular distributions from the first LHC pp collisions at center-of-mass energy sqrt(s) = 7 TeV have been measured with the ATLAS detector. The dataset used for this analysis represents an integrated luminosity of 3.1 pb-1. Dijet $\chi$ distributions and centrality ratios have been measured up to dijet masses of 2.8 TeV, and found to be in good agreement with Standard Model predictions. Analysis of the $\chi$ distributions excludes quark contact interactions with a compositeness scale $\Lambda$ below 3.4 TeV, at 95% confidence level, significantly exceeding previous limits.
7328744
Search for lepton flavour violation in ep collisions at HERA
A search for the lepton flavour violating processes ep→μX and ep→τX is performed with the H1 experiment at HERA. Final states with a muon or tau and a hadronic jet are searched for in a data sample corresponding to an integrated luminosity of 66.5 pb-1 for e+p collisions and 13.7 pb-1 for e-p collisions at a centre-of-mass energy of 319 GeV. No evidence for lepton flavour violation is found. Limits are derived on the mass and the couplings of leptoquarks inducing lepton flavour violation in an extension of the Buchmüller–Rückl–Wyler effective model. Leptoquarks produced in ep collisions with a coupling strength of λ=0.3 and decaying with the same coupling strength to a muon–quark pair or a tau–quark pair are excluded at 95% confidence level up to masses of 459 GeV and 379 GeV, respectively.
45984649
Search for pair production of a new b' quark that decays into a Z boson and a bottom quark with the ATLAS detector.
A search is reported for the pair production of a new quark b' with at least one b' decaying to a Z boson and a bottom quark. The data, corresponding to 2.0 fb(-1) of integrated luminosity, were collected from pp collisions at √s = 7 TeV with the ATLAS detector at the CERN Large Hadron Collider. Using events with a b-tagged jet and a Z boson reconstructed from opposite-charge electrons, the mass distribution of large transverse momentum b' candidates is tested for an enhancement. No evidence for a b' signal is detected in the observed mass distribution, resulting in the exclusion at a 95% confidence level of b' quarks with masses m (b') < 400 GeV that decay entirely via b' → Z+b. In the case of a vectorlike singlet b' mixing solely with the third standard model generation, masses m(b') < 358 GeV are excluded.
125487516
Observation of direct CP violation in $B^0 \to K^+ \pi^-$ decays
We present an updated search for direct CP violation in the decay B0 -> K+pi-. Using 227 million Y(4S) -> BBbar decays collected with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC, we observe a total signal yield of n(K-pi+) + n(K+pi-) = 1606 +- 51 decays and measure the asymmetry [n(K-pi+)-n(K+pi-)]/[n(K-p+-)+n(K+pi-)] = -0.133+-0.030 (stat) +- 0.009 (syst). This measurement establishes direct CP violation in the B0 meson system at the level of 4.2 standard deviations.