15930852
On the BRST structure of W(3) gravity coupled to c = 2 matter
We present some explicit results on the structure of singular vectors in $c=2$ Verma modules of the $\cW_3$ algebra. Using the embedding patterns of those vectors we construct resolutions for the $c=2$ irreducible modules, and thus are able to compute some of the BRST cohomology of $\cW_3$ gravity coupled to $c=2$ matter. In particular, we determine the states in the ground ring of the theory. (To appear in the proceedings of the AMS Special Session on "Geometry and Physics", USC, Los Angeles, November 5-6, 1992)
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
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.
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.
21928269
Large Dynamic Range Beam Profile Measurement in a High Background Environment
Beam profile measurements using a scanning target and loss monitor in the Fermilab Main Ring extraction channel have long proved their usefulness as a diagnostic method in analyzing extraction problems. To extend these measurements to a sensitivity greater than in the present system a different technique has been employed. A simple three element particle telescope viewing the scanning target allows a sensitive measurement of the tail on the edges of the beam profiles as well as the relative particle densities of the extracted beam and the circulating beam in the Main Ring. Both these regions are of significant interest in understanding extraction losses. The details of the profile measurement technique, some results using the telescope and possible methods of improving the measurements are discussed.
118465517
Prompt charm production in pp collisions at sqrt(s)=7 TeV
Charm production at the LHC in pp collisions at s√=7 TeV is studied with the LHCb detector. The decays D0→K−π+, D+→K−π+π+, D⁎+→D0(K−π+)π+, D+s→ϕ(K−K+)π+, Λ+c→pK−π+, and their charge conjugates are analysed in a data set corresponding to an integrated luminosity of 15 nb−1. Differential cross-sections dσ/dpT are measured for prompt production of the five charmed hadron species in bins of transverse momentum and rapidity in the region 0<pT<8 GeV/c and 2.0<y<4.5. Theoretical predictions are compared to the measured differential cross-sections. The integrated cross-sections of the charm hadrons are computed in the above pT-y range, and their ratios are reported. A combination of the five integrated cross-section measurements gives σ(cc¯)pT<8 GeV/c,2.0<y<4.5=1419±12(stat)±116(syst)±65(frag) μb, where the uncertainties are statistical, systematic, and due to the fragmentation functions.
118521922
Implications of LHCb measurements and future prospects
During 2011 the LHCb experiment at CERN collected 1.0 fb−1 of $\sqrt{s} = 7\mbox{~TeV}$pp collisions. Due to the large heavy quark production cross-sections, these data provide unprecedented samples of heavy flavoured hadrons. The first results from LHCb have made a significant impact on the flavour physics landscape and have definitively proved the concept of a dedicated experiment in the forward region at a hadron collider. This document discusses the implications of these first measurements on classes of extensions to the Standard Model, bearing in mind the interplay with the results of searches for on-shell production of new particles at ATLAS and CMS. The physics potential of an upgrade to the LHCb detector, which would allow an order of magnitude more data to be collected, is emphasised.
123077697
A New measurement of the spin dependent structure function g1(x) of the deuteron
Abstract We present a new measurement of the spin-dependent structure function g 1 d of the deuteron in deep inelastic scattering of 190 GeV polarised muons on polarised deuterons, in the kinematic range 0.003 x 2 Q 2 2 . This structure function is found to be negative at small x . The first moment Γ 1 d =∫ 0 1 g 1 d d x evaluated at Q 0 2 = 10 GeV 2 is 0.034 ± 0.009 (stat.) ± 0.006 (syst.). This value is below the Ellis-Jaffe sum rule prediction by three standard deviations. Using our earlier determination of Γ 1 p , we obtain Γ 1 p − Γ 1 n = 0.199 ± 0.038 which agrees with the Bjorken sum rule.
121728743
Charge distribution of the even Nd isotopes
Abstract : High energy electron scattering has been used to deduce the nuclear charge distribution of the isotopes 142, 144, 146, 148, 150Nd. The measured cross sections have been fitted using a two- and a three-parameter Fermi shape. A significant increase of the surface thickness between 142Nd and 150Nd is observed. The data for 142Nd at high momentum transfer can only be fitted by introducing a modification on the charge distribution which is due to shell model effects. (Author)