ATLAS

Abstract:

Cross sections for e+p charged current deep inelastic scattering at a centre-of-mass energy of 318 GeV have been determined with an integrated luminosity of 60.9 pb-1 collected with the ZEUS detector at HERA. The differential cross sections dσ/dQ2, dσ/dx and dσ/dy for Q2 > 200 GeV2 are presented. In addition, d2σ/dxdQ2 has been measured in the kinematic range 280 GeV2 < Q2 < 17 000 GeV2 and 0.008 < x < 0.42. The predictions of the Standard Model agree well with the measured cross sections. The mass of the W boson propagator is determined to be MW = 78.9 ± 2.0 (stat.) ± 1.8 (syst.) -1.8+2.0 (PDF) GeV from a fit to dσ/dQ2. The chiral structure of the Standard Model is also investigated in terms of the (1-y)2 dependence of the double-differential cross section. The structure-function F2CC has been extracted by combining the measurements presented here with previous ZEUS results from e-p scattering, extending the measurement obtained in a neutrino-nucleus scattering experiment to a significantly higher Q2 region.

Abstract:

We present a measurement of the mass difference m(Ds+) -m(D+), where both the Ds+ and D+ are reconstructed in the φπ+ decay channel. This measurement uses 11.6 pb-1 of data collected by CDF II using the new displaced-track trigger. The mass difference is found to be m(D s+)-m(D+) = 99.41±0.38(stat) ±0.21(syst) MeV/c2. copy; 2003 The American Physical Society.

Abstract:

This report describes how one can integrate the muon absorber with the focusing coils of a SFOFO muon cooling channel [1]. The absorber material must be a low Z material that reduces the muon momentum with minimum scattering. The best materials to use for muon ionization cooling absorbers are hydrogen, helium, lithium hydride, lithium, and beryllium. Hydrogen or helium in an absorber would normally be in the liquid state, Lithium hydride, lithium, and beryllium would normally be in the solid state. This report limits the absorber materials discussed to hydrogen, helium, lithium, and beryllium. In order to achieve the same level of ionization cooling with a solid absorber as a liquid hydrogen absorber, the beta of the muon beam must be reduced more than a factor of two. This affects both the designs of the absorber and the magnet around it. Reducing the beam beta reduces the momentum acceptance of the channel. Integration of a liquid hydrogen absorber and solid absorbers with a superconducting focusing solenoid is discussed. The choice of absorber material affects the design of the superconducting focusing magnet and the superconductor that is used to generate the magnetic field.