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.
119018357
On Root Multiplicities of Some Hyperbolic Kac–Moody Algebras
Using the coset construction, we compute the root multiplicities at level-3 for some hyperbolic Kac–Moody algebras including the basic hyperbolic extension of A11 and E10.
120400467
An Introduction to Yangian Symmetries
We review some aspects of the quantum Yangians as symmetry algebras of two-dimensional quantum field theories. The plan of these notes is the following: 
 
1 
 
The classical Heisenberg model: 
 
 
 
 
 
 
 
 
 
Non-Abelian symmetries; 
 
 
The generators of the symmetries and the semi-classical Yangians; 
 
 
An alternative presentation of the semi-classical Yangians; 
 
 
Digression on Poisson-Lie groups. 
 
 
Non-Abelian symmetries and the quantum Yangians; 
 
 
The transfer matrix and an alternative presentation of the Yangians; 
 
 
Digression on the double Yangians. 
 
 
 
 
 
2 
 
The quantum Heisenberg chain: 
 
 
 
 
 
 
 
 
 
Non-Abelian symmetries and the quantum Yangians; 
 
 
The transfer matrix and an alternative presentation of the Yangians; 
 
 
Digression on the double Yangians.
15502559
Anomalous scaling in the N-point functions of a passive scalar.
A recent analysis of the 4-point correlation function of the passive scalar advected by a time-decorrelated random flow is extended to the N-point case. It is shown that all stationary-state inertial-range correlations are dominated by homogeneous zero modes of singular operators describing their evolution. We compute analytically the zero modes governing the N-point structure functions and the anomalous dimensions corresponding to them to the linear order in the scaling exponent of the 2-point function of the advecting velocity field. The implications of these calculations for the dissipation correlations are discussed.
2671755
Logarithmic Yangians in WZW Models
A new action of the Yangians in the WZW models is displayed. Its structure is generic and level-independent. This Yangian is the natural extension at the conformal point of the one unraveled in massive theories with current algebras. Hopefully, this new symmetry of WZW models will lead to a deeper understanding of the integrable structure of conformal field theories and their deformations.
17641456
Spin-Charge Separation and the Spin Quantum Hall Effect
We use quantum field theory methods to study the network model for the spin quantum hall transition. When the couplings are fine tuned in a certain way, the spin and charge degrees of freedom, corresponding to the su-percurrent algebras su(2) 0 and osp(2|2) −2 respectively, completely decouple. This simpler theory is exactly solvable and some critical exponents are computed and shown to agree with the recent predictions based on percolation. The general network model is shown to be in a different universality class by identifying the attractive direction of the renormalization group flow.
15095539
Search for a dark photon in e(+)e(-) collisions at BABAR.
Dark sectors charged under a new Abelian interaction have recently received much attention in the context of dark matter models. These models introduce a light new mediator, the so-called dark photon (A^{'}), connecting the dark sector to the standard model. We present a search for a dark photon in the reaction e^{+}e^{-}→γA^{'}, A^{'}→e^{+}e^{-}, μ^{+}μ^{-} using 514  fb^{-1} of data collected with the BABAR detector. We observe no statistically significant deviations from the standard model predictions, and we set 90% confidence level upper limits on the mixing strength between the photon and dark photon at the level of 10^{-4}-10^{-3} for dark photon masses in the range 0.02-10.2  GeV. We further constrain the range of the parameter space favored by interpretations of the discrepancy between the calculated and measured anomalous magnetic moment of the muon.
116971112
Search for B0 Meson Decays to pi0 K0(S) K0(S), eta K0(S) K0(S), and eta-prime K0(S) K0(S)
We describe searches for B-0 meson decays to the charmless final states pi(KSKS0)-K-0-K-0, eta(KSKS0)-K-0, and eta(KSKS0)-K-'-K-0. The data sample corresponds to 467x10(6) BB pairs produced in e(+)e(-) annihilation and collected with the BABAR detector at the SLAC National Accelerator Laboratory. We find no significant signals and determine the 90% confidence level upper limits on the branching fractions, in units of 10(-7), B(B-0 ->pi(KSKS0)-K-0-K-0) eta(KSKS0)-K-0) eta(KSKS0)-K-'-K-0)< 20.
53513788
On triple focusing dipole magnets
Abstract We present a general, paraxial study of triple focusing (i.e., stigmatic and non-dispersive) index-free dipole magnets. The transcendental equations which describe such magnets lead to a second-degree polynomial equation which we solve analytically. The two solutions of this equation correspond to magnets having either one or no intermediate focal points in the vertical direction. The first-order optical properties of the physical solutions are studied.
51745482
Status of the DIRC Detector at Babar: Early Operational Experience
A novel type of Cherenkov ring imaging particle identification system (DIRC) based on the detection of ring images produced in long, fused silica radiator bars is being used to provide hadronic particle identification in the BABAR detector at PEP-II. The DIRC concept, design, fabrication, and initial performance will be briefly described. The DIRC is now fully commissioned, and has been operating in the BABAR detector on beam line at the PEP-II B Factory since late Spring 1999.
209869059
Measurements of branching fractions, polarizations, and direct CP-violation asymmetries in $B \to \rho K^{*}$ and $B \to f_0(980) K^{*}$ decays