119680796
Multiperipheral Model for Pomeranchukon Couplings
An intimate connection between the Pomeranchukon and the $f$ and ${f}^{\ensuremath{'}}$ Regge trajectories is derived in the context of a specific multiperipheral model, embodying duality. The explicit dependence of the Pomeranchukon couplings on the $f$ (and ${f}^{\ensuremath{'}}$) Regge poles clarifies certain features of diffraction scattering data.
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.
121755839
PHASE CONTOURS AND BOOTSTRAPS. I.
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.
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.
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.
56287781
Estimating the Cost of Large Superconducting Thin Solenoid Magnets
The cost of thin superconducting solenoid magnets can be estimated if one knows the magnet stored energy, the magnetic field volume product or the overall mass of the superconducting coil and its cryostat. This report shows cost data collected since 1979 for large superconducting solenoid magnets used in high energy physics. These magnets are characterized in most cases by the use of indirect two phase helium cooling and a superconductor stabilizer of very pure aluminum. This correlation can be used for making a preliminary cost estimate of proposed one of a kind superconducting magnets. The magnet costs quoted include the power supply and quench protection system but the cost of the helium refrigerator and helium distribution system is not included in the estimated cost.
136566290
MODELING OF PROXIMITY COUPLING BETWEEN SUPERCONDUCTING FILAMENTS IN SUPERCONDUCTING DIPOLE MAGNETS
There is strong experimental evidence for superconducting current coupling between filaments in fine filament multifilamentary Nb-Ti which has been proposed for the SSC. The coupling between the fine filaments appears to be a Type II superconducting coupling. As a result, a.c. loss and magnetization can increase as one reduces the filament size in a fine filamentary conductor. This paper presents a computer model which fits experimental data for proximity superconducting coupling between filaments in a superconductor matrix. Using this model, one can predict the effect of proximity coupling on the field uniformity of a dipole magnet for the SSC.
121004261
A burnout safety condition for superconducting magnets and some of its applications
From the time evolution of the current in a superconducting coil during a quench, an upper limit can be computed for the temperature reached anywhere in the coil. A condition under which the danger of burnout is eliminated is derived here. It is used to show how the tests of superconducting magnets can be made safe against burnout and it provides constraints for the design of some type of magnets.
122748175
Calculation of the pressure rise in the cooling tube of a two-phase cooling system during a quench of an indirectly cooled superconducting magnet
Large superconducting detector magnets are indirectly cooled with two-phase helium flowing in cooling tubes attached to the coil or its support structure. Large detector magnets often quench such that most of the magnet stored energy ends up as heat stored in the coil package. The time constant for energy deposition in the coil and support structure is often quite short. This paper presents a method for calculating the peak pressure rise in the magnet two-phase cooling tube during a magnet quench. A comparison of calculated peak pressure rise and measured pressure rise for the PEP-4 solenoid is presented in this report. >
108163413
Progress on the MICE RFCC Module for the MICE Experiment
PROGRESS ON MICE RFCC MODULE FOR THE MICE EXPERIMENT* Allan DeMello, Nord Andresen, Michael Green, Derun L i , Heng Pan, Steve Virostek, Michael Zisman ( L B N L , Berkeley C A 94720, USA), Don Summers, Mike Reep (University of Mississippi, Oxford M S 38677, USA) An Bin Chen, Xiao-Kun Liu, Feng-Yu X u , Shi-Xian Zheng (HIT, Harbin, China), Yun Cao, Sen Sun, L i Wang, Lixin Y i n (SINAP, Shanghai, China) Abstract We describe the recent progress on the design and fabrication of the R F C C (RF and Coupling Coil) module for the international Muon Ionization Cooling Experiment (MICE). The M I C E cooling channel has two R F C C modules; each has four 201-MHz normal conducting R F cavities and one superconducting solenoid magnet. The magnet is designed to be cooled by three cryocoolers. Fabrication of the R F cavities is complete; design and fabrication of the magnets are in progress. The first magnet is expected to be finished by the end of 2011. pneumatic actuator (Fig. 3). Six flexure tuners are currently being fabricated (University of Mississippi) for a full cavity test of the R F tuner system. This test will include the electronic pressure control, EPICS software interface and the R F feedback system. This system will be assembled into a single cavity vacuum vessel (see below) for testing. INTRODUCTION M I C E is an international experiment designed to demonstrate muon beam cooling using ionization cooling (Fig. 1). Muons are captured in a strong magnetic field, cooled in 4D phase space and re-accelerated in the beamline direction by the normal conducting R F cavities in the R F C C . This demonstration is key to the success of a future Neutrino Factory or Muon Collider. The experiment is being hosted at Rutherford Appleton Laboratory ( R A L ) in the U K , where beamline commissioning is underway. Institutions participating in the collaboration include national laboratories and universities in Europe, the U.S., China, and Japan. Figure 2: 90° sectioned view of the M I C E cooling channel R F C C module. Figure 1 : The M I C E cooling channel. RFCC M O D U L E CAVITIES Lawrence Berkeley National Laboratory is responsible for the design of the R F Cavity and Coupling Coil (RFCC) module for M I C E (Fig. 2). Each R F C C module will contain four 201 M H z normal conducting R F cavities and one superconducting coupling coil magnet [4]. Each cavity will have its frequency actively tuned using six stainless steel flexure tuners moved with a dual action * This work was supported by the Office of Science, U.S. Department of Energy under D O E contract number DE-AC02-05CH11231. Figure 3: The prototype RF tuner flexure and actuator mounted on a 201-MHz cavity.