4,123 research outputs found
The Scalar Quarkonium Spectrum and Quarkonium-Glueball Mixing
We evaluate the valence approximation to the mass of scalar quarkonium and to
the mixing energy between scalar quarkonium and the lightest scalar glueball
for a range of different lattice sizes and quark masses. Our results support
the identification of as the lightest scalar glueball.Comment: 3 pages, 4 PostScript figures, talk given at Lattice 9
Continuum Limit of Scalar Masses and Mixing Energies
We evaluate the continuum limit of the valence approximation to the mass of
scalar quarkonium and to the scalar quarkonium-glueball mixing energy for a
range of different quark masses. Our results answer several questions raised by
the proposed identification of as composed primarily of the
lightest scalar glueball.Comment: 3 pages, 2 PostScript figures, LATTICE98(spectrum), one reference
correcte
On the Dependence of the Q-Value on the Accelerating Gradient for Superconducting Cavities
The performance of niobium superconducting cavities for accelerator applications has improved considerably over the last decade. Individual cavities reach accelerating gradients close to the theoretical limit (about 50 MV/m), however sometimes at the expense of a re-treatment (baking, electro-polishing, rinsing) needed to eliminate an undesired decrease of the Q-value with the field gradient (Q-slope, Q-drop). Cures have been developed, but a generally accepted physical explanation is still missing. Furthermore, for successful research work on materials other than niobium, it is of utmost importance to understand better the limitations in gradient and Q-value of superconducting cavities. The paper presents an alternative explanation for the Q-slope and confronts it with experimental results for 352 and 1500 MHz cavities
On the Field Dependent Surface Resistance Observed in Superconducting Niobium Cavities
A quantitative description is presented of the non-linear current-voltage response in superconducting niobium cavities for accelerator application. It is based on a fit for a large sample of data from cavity tests of different kind. Trial functions for the surface resistance describing this non-linear relation are established by a least square data fit. Those trial functions yielding the best fit are quantitatively explained by basic physics
TIS General Safety Group: Annual Report 2000
This report summarises the main activities of the General Safety (GS) Group of the Technical Inspection and Safety Division (TIS) during the year 2000, and the results obtained. The different topics in which the Group is active are covered: general safety inspections and ergonomy, electrical, chemistry and gas safety, chemical pollution containment and control, industrial hygiene, the safety of civil engineering works and outside contractors, fire prevention and the safety aspects of the LHC experiments
The General Safety Group: Annual Report 2001/2002
This report summarizes the main activities of the General Safety (GS) Group of the Technical Inspection and Safety Division during 2001 and 2002, and the results obtained. The different topics in which the group is active are covered: general safety inspections and ergonomics, electrical, chemical and gas safety, chemical pollution containment and control, industrial hygiene, the safety of civil engineering works and outside contractors, fire prevention and the safety aspects of the LHC experiments
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