120524357
Point-like particles and off-shell supersymmetry algebras
Abstract The reparametrization invariant action, describing supersymmetric particles, is shown to have a non-local symmetry and consequently an enlarged, N = 2, supersymmetry invariance with a central charge. The construction of multiplets of states only involves physical operators - there are no auxiliary states in the theory, even though the supersymmetry algebra applies off-shell. The free field action is described in terms of superfields which are Clifford operators. Comments are made about analogous string theories.
123230985
Off-shell states in the dual model
Abstract We present a class of Lorentz invariant, gauge invariant off-shell amplitudes for the ordinary Veneziano and Ramond-Neveu-Schwarz dual models. They correspond to interactions with the string which are local in space-time.
121062482
N=4 Yang-Mills and N=8 Supergravity as Limits of String Theories
The formulation of supersymmetric string theories in ten dimensions is generalized to incorporate compactified dimensions. Expressions for the one-loop four-particle S -matrix elements of N = 4 Yang-Mills and N = 8 supergravity in four dimensions are obtained by studying the string-theory loop amplitudes in the limit that the radii of the compactified dimensions and the Regge slope parameter simultaneously approach zero. If certain patterns that emerge should persist in the higher orders of perturbation theory, then N = 4 Yang-Mills in four dimensions would be ultraviolet finite to all orders, whereas N = 8 supergravity in four dimensions would have ultraviolet divergences starting at three loops.
9607753
Anomalous creation of branes
In certain circumstances when two branes pass through each other a third brane is produced stretching between them. We explain this phenomenon by the use of chains of dualities and the inflow of charge that is required for the absence of chiral gauge anomalies when pairs of D-branes intersect.
120539667
Anomaly cancellations in supersymmetric D = 10 gauge theory and superstring theory☆
Abstract Supersymmetric ten-dimensional Yang-Mills theory coupled to N = 1, D = 10 supergravity has gauge and gravitational anomalies that can be partially cancelled by the addition of suitable local interactions. The remaining pieces of all the anomalies cancel if the gauge group is SO(32) or E 8 × E 8 . These cancellations are automatically incorporated in the type I superstring theory based on SO(32). A superstring theory for E 8 × E 8 has not yet been constructed.
121755839
PHASE CONTOURS AND BOOTSTRAPS. I.
122299493
The Effect of Flux Creep on the Magnetization Field in the SSC Dipole Magnets
The sextupole fields of model SSC dipole magnets have been observed to change with time when the magnets are held at constant current under conditions similar to injection into the SSC accelerator. The changes in the sextupole component have close to a linear log time dependence, and is felt to be caused by flux creep decay of the magnetization currents in the superconductor filaments. Measurements of this decay have been made under various conditions. The conditions include various central field inductions and changes of field prior to when the decay was measured. The measured field decay in the dipole’s sextupole is proportional to the magnitude and sign of the sextupole due to magnetization which was measured at the start of the decay. This suggests that the decay is a bulk superconductivity flux creep. Proximity coupling appears to play only a minor role in the flux creep according to recent LBL measurements with a stable power supply.
107306043
COMPUTER DESIGN AND OPTIMIZATION OF CRYOGENIC REFRIGERATION SYSTEMS
The design and optimization of a cryogenic refrigerator using the LBL computer program GEOTHM are described. This computer program has been used extensively to design and optimize geothermal power plants and power cycles of other types. GEOTHM can calculate the thermodynamics of a wide variety of cycles including refrigeration cycles. GEOTHM has an optimizer which permits single step multiparameter optimization of a thermodynamic cycle. A refrigeration cycle may be optimized for minimum cost refrigeration, or maximum thermodynamic performance using up to 55 optimizable parameters. The use of the optimizer in GEOTHM is demonstrated on two liquid nitrogen refrigeration cycles which are optimized for minimum refrigeration cost and minimum input power.
136709664
SCMAG series of programs for calculating superconducting dipole and quadrupole magnets
54892068
GROUND PLANE INSULATION FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL
mm I UNIVERSITY OF CALIFORNIA LBL-12326 C Q k A • V.IL . V U . I Lawrence Berkeley Laboratory Engineering & Technical Services Division To b e p r e s e n t e d a t t h e 7 t h I n t e r n a t i o n a l C o n f e r e n c e on Magnet T e c h n o l o g y , K a r l s r u h e , West Germany, March 3 0 - A p r l l 3 , 1 9 8 1 ; and t o be p u b l i s h e d In t h e P r o c e e d i n g s GROUND-PLANE INSULATION FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL M.A. G r e e n , P . Del P i e r r e , K. D e r b y , J . M . D u O l i v a r e s , P . H . E b e r h a r d , B . T . F u l t z , R.D. G i a u q u e , G.H. G i b s o n , F . S . G o u l d i n g , J . I . Kim, P . S . M a r t i n , J . W . M o r r i s , M. P r i p s t e i n , R.R. R o s s , M.D. S h a p i r o , E.G. S m i t s , and J . D . T a y l o r March Prepared for the U.S. Department ot Energy under Contract W-7405-ENG-4B MsmiurtoN OF THIS n u r is WIUUTEO
43416126
Design and Construction of a Prototype Solenoid Coil for MICE Coupling Magnets
A superconducting coupling solenoid mounted around four conventional RF cavities, which produces up to 2.6 T central magnetic field to keep the muons within the cavities, is to be used for the Muon Ionization Cooling Experiment (MICE). The coupling coil made from copper matrix NbTi conductors is the largest of three types of magnets in MICE both in terms of 1.5 m inner diameter and about 13 MJ stored magnetic energy at full operation current of 210 A. The stress induced inside the coil assembly during cool down and magnet charging is relatively high. In order to validate the design method and develop the coil winding technique with inside-wound SC splices required for the coupling coil, a prototype coil made from the same conductor and with the same diameter and thickness but only one-fourth long as the coupling coil was designed and fabricated by ICST. The prototype coil was designed to be charged to strain conditions that are equivalent or greater than would be encountered in the coupling coil. This paper presents detailed design of the prototype coil as well as developed coil winding skills. The analyses on stress in the coil assembly and quench process were carried out.