14731538
D-particle bound states and the D-instanton measure
A connection is made between the Witten index of relevance to threshold bound states of D-particles in the type IIA superstring theory and the measure that enters D-instanton sums for processes dominated by single multiply-charged D-instantons in the type IIB theory.
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.
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.
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.
117741073
Measurements of Magnetization Multipoles in Four Centimeter Quadrupoles for the SSC
Higher multipoles due to magnetization of the superconductor in superconducting dipole and quadrupole magnets has been observed in over twenty years. This report presents measurements of the 12 pole and 20 pole multipoles in a model one-meter long four-centimeter bore SSC type quadrupole built at the Lawrence Berkeley Laboratory (LBL). The measurements were compared with calculations of the field structure using magnetization theory. Good agreement was observed between the measured multipoles and the calculated multipoles. Under conditions equivalent to injection into the SSC at an energy of 2 TeV, about 1.0 unit of 12 pole was observed and 0.05 units of 20 pole was observed. (One unit of field error is a field error of one part in ten thousand). Magnetization multipole measurements were also done on the first full length (5 meter) SSC quadrupole prototype. Measurements of flux creep decay were made on three one meter quadrupoles and the first five meter long quadrupole. 7 refs., 9 figs.
121321569
A report on Russian magnet technology for use in phi factory and light source bending magnets
39829406
The Helium Cooling System and Cold Mass Support System for the MICE Coupling Solenoid
The MICE cooling channel consists of alternating three absorber focus coil module (AFC) and two RF coupling coil module (RFCC) where the process of muon cooling and reacceleration occurs. The RFCC module comprises a superconducting coupling solenoid mounted around four conventional conducting 201.25 MHz closed RF cavities and producing up to 2.2 T magnetic field on the centerline. The coupling coil magnetic field is to produce a low muon beam beta function in order to keep the beam within the RF cavities. The magnet is to be built using commercial niobium titanium MRI conductors and cooled by pulse tube coolers that produce 1.5 W of cooling capacity at 4.2 K each. A self-centering support system is applied for the coupling magnet cold mass support, which is designed to carry a longitudinal force up to 500 kN. This report will describe the updated design for the MICE coupling magnet. The cold mass support system and helium cooling system are discussed in detail.
122003703
Quench back in thin superconducting solenoid magnets
Abstract Superconducting magnets with well coupled, low resistance, secondary circuits have been observed to become fully normal faster than quench propagation in the coil would permit. This process is referred to as ‘quench back’. Quench back observed at the Lawrence Berkeley Laboratory (LBL) was caused by heating the secondary circuit from the current induced from the primary circuit as normal region in the superconducting coil propagated. This paper develops the theory for thermal quench back in thin solenoid magnets and compares this theory with measurements made in two one-meter diameter superconducting solenoid magnets.
29833302
Muon phase rotation using an induction linac
The proposed neutrino factory requires that the muons produced by the decay of pions and kaons produced by a target be phase-rotated before they can be cooled and then accelerated. This report describes a muon phase-rotation system that employs an induction acceleration system. The phase-rotation system consists of a 100-meter long induction accelerator, a mini-cooling system with magnetic flux reversal, and two 80-meter long induction linacs with a drift space between them. The induction linac phase-rotation system uses a 620-mm warm bore 1.25 T superconducting solenoid to guide the muons in the beam channel. The phase-rotation linac is divided into 1-meter long components each with its superconducting solenoid. This report describes the induction cells, the induction cell power system, and the superconducting solenoid contained within those cells.