50292897
Operator algebra of the 4-D W(3) string
The noncritical 4D W3 string is a model of W3 gravity coupled to two free scalar fields. In this paper we discuss its BRST quantization in direct analogy with that of the 2D (Virasoro) string. The physical operators form a BV-algebra. We model this BV-algebra on that of the polyderivations of a commutative ring on six variables with a quadratic constraint, or, equivalently, on the BV-algebra of (polynomial) polyvector fields on the base affine space ofSL(3,C).
122808498
Covariant field theory of the compactified closed bosonic string
We covariantly first-quantize, via the BRST approach, the closed bosonic string compactified on a torus — in particular the 18-dimensional theory with E8 × E8 gauge bosons. Further, we give the corresponding free field theory. Thus the model is ready for the introduction of string interactions, and may be very useful for the study of gauge interactions in string theories.
2823704
BV Structure of the Cohomology of Nilpotent Subalgebras and the Geometry of(W) Strings
AbstractGiven a simple, simply laced, complex Lie algebra 
$$\mathfrak{g}$$
corresponding to the Lie group G, let 
$$\mathfrak{n}_ + $$
 be thesubalgebra generated by the positive roots. In this Letter we construct aBV algebra 
$${\text{BV}}[\mathfrak{g}]$$
 whose underlying graded commutative algebra is given by the cohomology, with respect to 
$$\mathfrak{n}_ + $$
, of the algebra of regular functions on G with values in 
$$ \wedge (\mathfrak{n}_ + \backslash \mathfrak{g})$$
. We conjecture that 
$${\text{BV}}[\mathfrak{g}]$$
 describes the algebra of allphysical (i.e., BRST invariant) operators of the noncritical 
$$\mathcal{W}[\mathfrak{g}]$$
string. The conjecture is verified in the two explicitly known cases,
$$\mathfrak{g} = \mathfrak{s}\mathfrak{l}$$
2 (the Virasoro string) and 
$$\mathfrak{g} = \mathfrak{s}\mathfrak{l}$$
3 (the 
$$\mathcal{W}_3 $$
 string).
120560048
Free Field Approach to 2-Dimensional Conformal Field Theories
122935088
Minimal models on Riemann surfaces
Abstract We extend the Coulomb gas representation of minimal model correlation functions to higher genius Riemann surfaces. Specifically, we incorporate the “BRS” structure of this representation into the operator formalism. This allows traces over the spectrum of a minimal model to be computed from traces over Fock spaces of a free scalar field. This our results are obtained by standard sewing techniques. The formulation is general, but we present here in particular the two-loop characters of the Ising model.
11851007
Fusing the coordinates of quantum superspace
Abstract We introduce the notion of a fused quantum superplane by allowing for terms θθ ∼ x in the defining relations. We develop the differential calculus for a large class of fused quantum superplanes related to particular solutions of the Yang-Baxter equation.
123125911
Model calculation of nucleon structure functions
Deep inelastic polarized and unpolarized structure functions for a free nucleon are obtained in a modified center-of-mass bag model, which includes the symmetry-breaking effects from spin-dependent interactions. The quark distribution functions, calculated at [ital Q][sub 0][sup 2][congruent](0.9 GeV/[ital c])[sup 2], are evolved to a higher [ital Q][sup 2] region and compared with the data and other models. The model gives a reasonable description for the valence part of the structure functions at [ital x][gt]0.3. For the small-[ital x] region, the contributions from the sea are necessary. The spin-dependent effects are important in describing the existing data.
120666175
A THERMODYNAMICAL BAG MODEL FOR THE NUCLEON SPIN
A thermodynamical bag model was developed to study the nucleon spin. Equations of state for the bag are deduced and solved self-consistently. The recent experimental data of the SMC and the E143 collaboration and the Bjorken sum rule are completely explained within the framework of the model.
122989017
Measurement of the SMC muon beam polarisation using the asymmetry in the elastic scattering off polarised electrons
A muon beam polarimeter was built for the SMC experiment at the CERN SPS, for beam energies of 100 and 190 GeV. The beam polarisation is determined from the asymmetry in the elastic scattering off the polarised electrons of a ferromagnetic target whose magnetisation is periodically reversed. At muon energies of 100 and 190 GeV the measured polarisation is P-mu = -0.80 +/- 0.03 (stat.) +/- 0.02 (syst.) and P-mu = - 0.797 +/- 0.011 (stat.) +/- 0.012 (syst.), respectively. These results agree with measurements of the beam polarisation using a shape analysis of the decay positron energy spectrum. (C) 2000 Elsevier Science B.V. All rights reserved.
22966047
Measurement of the $\Lambda_b^0$, $\Xi_b^-$ and $\Omega_b^-$ baryon masses
Bottom baryons decaying to a J/\psi\ meson and a hyperon are reconstructed using 1.0 fb^{-1} of data collected in 2011 with the LHCb detector. Significant \Lambda_b^0 \rightarrow J/\psi \Lambda, \Xi_b^-\rightarrow J/\psi \Xi^- and \Omega_b^- \rightarrow J/\psi \Omega^- signals are observed and the corresponding masses are measured to be M(\Lambda_b^0) = 5619.53 \pm 0.13 (stat) \pm 0.45 (syst) MeV/c^2, M(\Xi_b^-) = 5795.8 \pm 0.9 (stat) \pm 0.4 (syst) MeV/c^2, M(\Omega_b^-) = 6046.0 \pm 2.2 (stat) \pm 0.5 (syst) MeV/c^2, while the differences with respect to the \Lambda_b^0 mass are M(\Xi_b^-)-M(\Lambda_b^0) = 176.2 \pm 0.9 (stat) \pm 0.1 (syst) MeV/c^2, M(\Omega_b^-)-M(\Lambda_b^0) = 426.4 \pm 2.2 (stat) \pm 0.4 (syst) MeV/c^2. These are the most precise mass measurements of the \Lambda_b^0, \Xi_b^- and \Omega_b^- baryons to date. Averaging the above \Lambda_b^0 mass measurement with that published by LHCb using 35 pb^{-1} of data collected in 2010 yields M(\Lambda_b^0) = 5619.44 \pm 0.13 (stat) \pm 0.38 (syst) MeV/c^2.
122523656
A large Streamer Chamber muon tracking detector in a high-flux fixed-target application
Arrays of limited streamer tubes of the Iarocci type were deployed in our experiment at CERN as part of a forward muon detector system with provisions for the beam to pass through the center of each panel in the array. A total of 16 4 m x 4 m panels were assembled with inductive readout strips on both sides of each panel. An active feedback system. was deployed to regulate the high voltage to the streamer tubes to insure a constant efficiency for minimum ionizing particles. The arrays were operated in this environment for over five years of data taking. Streamer tube track-reconstruction efficiencies and tube replacement rates are reported. (C) 1999 Elsevier Science B.V. All rights reserved.