46193102
Experimental study of electron acceleration by plasma beat-waves with Nd lasers
We have observed the acceleration of electrons by a beat-wave generated in a deuterium plasma by two Nd-YAG and Nd-YLF laser wavelengths. Electrons injected at an energy of 3.3 MeV are observed to be accelerated up to 4.7 MeV after the plasma. The energy gain is compatible with a peak electric field of the order of 1.2 GV/m. The experiment has been performed with different injection energies, from 2.5 to 3.3 MeV, with different plasma dimensions, and with different laser intensities.
202048438
Branching fraction for $B^{+} \to \pi^0 \ell^{+} \nu$, measured in $\upsilon_{4S} \to B \bar{B}$ events tagged by $B^{-} \to D^0 \ell^{-}$ anti-v ($X$) decays
126404399
Measurements of branching fractions and CP-violating asymmetries in B-meson decays to the charmless two-body states K0 pi+, anti-K0 K+, and K0 anti-K0
120104270
Operation of the Cherenkov detector DIRC of BABAR at high luminosity
The DIRC (acronym for Detection of Internally Reflected Cherenkov (light)) is the ring imaging Cherenkov detector of the BABAR detector at the PEP-II ring of SLAC. It provides the identification of pions, kaons and protons for momenta up to 4 GeV/c with high efficiency. This is needed to reconstruct CP-violating B-decay final states and to provide B-meson flavour tagging for time dependent asymmetry measurements. The DIRC radiators consists of long rectangular bars made of synthetic fused silica and the photon detector is a water tank equipped with an array of 10.752 conventional photomultipliers. At the end of the year 2000 BABAR has recorded about 22 million B~B pairs reaching the design luminosity of L=3/spl middot/10/sup 33//cm/sup 2/s. The ability to keep the beam background level low at highest collision rates and the long term reliability of the DIRC components during continuous data taking are requirements of BABAR to accomplish its physics program.
160033287
Improved Measurement of CP Violation in Neutral B Decays to c cs
125343210
Measurement of the CKM matrix element $|V_{ub}|$ with $B \to \rho e \nu$ decays
122504263
Fractional supersymmetries in perturbed coset CFTs and integrable soliton theory
Abstract We study integrable perturbations of the coset CFTs. The models are characterized by two fractional supersymmetries that are dual to each other. Generally, these models can be considered as restrictions of new integrable field theories we call fractional super soliton field theories. We study the connections with other models such as perturbations of WZW models, super sine-Gordon theory, Gross-Neveu models, and principal chiral models.
15202743
Poisson algebra of 2d dimensionally reduced gravity
Using a Lax pair based on twisted affine sl(2,) Kac-Moody and Virasoro algebras, we deduce an r-matrix formulation of two-dimensional reduced vacuum Einstein's equations. Whereas the fundamental Poisson brackets are non ultralocal, they lead to pure c-number modified Yang-Baxter equations. We also describe how to obtain classical observables by imposing reasonable boundary conditions.
14202711
Off-Critical SLE(2) and SLE(4): A Field Theory Approach
Using their relationship with the free boson and the free symplectic fermion, we study the off-critical perturbations of SLE(4) and SLE(2) obtained by adding a mass term to the action. We compute the off-critical statistics of the source in the Loewner equation describing the two-dimensional interfaces. In these two cases we show that ratios of massive and massless partition functions, expressible as ratios of regularized determinants of massive and massless Laplacians, are (local) martingales for the massless interfaces. The off-critical drifts in the stochastic source of the Loewner equation are proportional to the logarithmic derivative of these ratios. We also show that massive correlation functions are (local) martingales for the massive interfaces. In the case of massive SLE(4), we use this property to prove a factorization of the free boson measure.
119138757
2D growth processes: SLE and Loewner chains
Abstract This review provides an introduction to two dimensional growth processes. Although it covers a variety of processes such as diffusion limited aggregation, it is mostly devoted to a detailed presentation of stochastic Schramm–Loewner evolutions (SLE) which are Markov processes describing interfaces in 2D critical systems. It starts with an informal discussion, using numerical simulations, of various examples of 2D growth processes and their connections with statistical mechanics. SLE is then introduced and Schramm's argument mapping conformally invariant interfaces to SLE is explained. A substantial part of the review is devoted to reveal the deep connections between statistical mechanics and processes, and more specifically to the present context, between 2D critical systems and SLE. Some of the remarkable properties of SLE are explained, together with the tools for computing with it. This review has been written with the aim of filling the gap between the mathematical and the physical literature on the subject.
18013997
Yang-Baxter equation in spin chains with long range interactions
We consider the $ su(n) $ spin chains with long range interactions and the spin generalization of the Calogero-Sutherland models. We show that their properties derive from a transfer matrix obeying the Yang-Baxter equation. We obtain the expression of the conserved quantities and we diagonalize them.