123491192
Some Conceptual Designs for a LASSY Spectrometer Magnet
- - - - - - - - - - - - - - - - - -...... ....,..~r'lJ-- IrnILawren ce. Berkeley Laboratory 11:1 UNIVERSITY OF CALIFORNIA Accelerator & Fusion Research Division Presented at the Workshop ona·Large Angle Spectrometer System, Berkeley, CA,September 16-17,1995, and to be .published in the Proceedings RECEIVED JAN2 Q&ir. Some Conceptual Designs for a LASSY Spectrometer Magnet M.A. Green September 1995 ii Prepared for the u.s. Department of Energy Under Contract Number DE-AC03-76SF00098
123081787
PROGRESS ON THE SUPERCONDUCTING MAGNET FOR THE TIME PROJECTION CHAMBER EXPERIMENT (TPC) AT PEP
The TPC (Time Projection Chamber) experiment at PEP will have a two meter inside diameter superconducting magnet which creatests a 1.5 T uniform solenoidal field for the TPC. The superconducting magnet coil, cryostat, cooling system, and the TPC gas pressure vessel (which operatests at 11 atm) were designed to be about two thirds of a radiation length thick. As a result, a high current density coil design was chosen. The magnet is cooled by forced flow two phase helium. The TPC magnet is the largest adiabatically stable superconducting magnet built to date. The paper presents the parameters of the TPC thin solenoid and its subsystems. Tests results from the Spring 1980 cryogenic tes are presented. The topics to be dealt with in the paper are cryogenic services and the tests of magnet subsystems such as the folded current leads. Large thin superconducting magnet technology will be important to large detectors to be used on LEP.
24392991
The Engineering Design of the 1.5 m Diameter Solenoid for the MICE RFCC Modules
The RF coupling coil (RFCC) module of MICE is where muons that have been cooled within the MICE absorber focus (AFC) modules are re-accelerated to their original longitudinal momentum. The RFCC module consists of four 201.25 MHz RF cavities in a 1.4 meter diameter vacuum vessel. The muons are kept within the RF cavities by the magnetic field generated by a superconducting coupling solenoid that goes around the RF cavities. The coupling solenoid will be cooled using a pair of 4 K pulse tube cooler that will generate 1.5 W of cooling at 4.2 K. The magnet will be powered using a 300 A two-quadrant power supply. This report describes the ICST engineering design of the coupling solenoid for MICE.
118834673
A Design for a Combined Function Superconducting Dipole for a Muon Collider FFAG Accelerator
The acceleration stages for a muon collider require that the muons be accelerated within a given ring in fewer than twenty turns. One type of accelerator that appears to be attractive for a synchrotron that accelerates the muon a factor of four in energy in a few turns is the Fixed Field Alternating Gradient (FFAG) type of accelerator. As the energy of the muon beam increases, the muons move toward a higher field region of a DC combined function dipole. The following dipole and quadrupole magnet characteristics are required for a muon FFAG machine to be successful: (1) The dipole will be a fixed field dipole with an impressed quadrupole and sextupole field. There may or may not be separate quadrupoles that mayor may not have added sextupole windings. (2) The horizontal aperture of the required good field region is wider than the vertical aperture of the required good field region. (3) The magnet is relatively short, so that the conventional SSC type of superconducting dipole or quadrupole ends can not be used. The field at the end of the magnet must fall off abruptly within the distance of less than one vertical aperture. For a magnet that is 400more » mm long, the end region can be no more than 80 mm long. (4) The structure of the integrated field within the end region must be the same as the structure of the two-dimensional filed at the center of the magnet. A very preliminary design concept for a FFAG combined function dipole is presented in this paper.« less
94844521
ACTIVE CENTER TAP QUENCH PROTECTION
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. >
122951619
Covariant description of superstrings
Abstract A Lorentz-covariant superstring action with ten-dimensional supersymmetry is presented. The action also possesses local supersymmetry that permits the choice of a light-cone gauge in which it reduces to one discussed previously.
119043809
Connections between M-theory and superstrings
This article reviews the non-perturbative structure of certain higher derivative terms in the type II string theory effective action and their connection to one-loop effects in eleven-dimensional supergravity compactified on a torus. New material is also included that was not presented in the talks.
120490134
Pomeron couplings in the presence of Reggeon loops
Abstract We examine the effect of reggeon loop corrections to the five-point function in the double-Regge limit. Using the Gribov reggeon calculus we first discuss the reggeon triangle insertion in the double-Regge pole vertex. This is seen to give rise to an inverse square root branch point in the plane of the azimuthal angle. Making specific smoothness assumptions we obtain constraints that require the vanishing of certain triple-Regge vertices. We discuss possible implications for the Brower-Weis decoupling theorem.
121743895
The vanishing of triple reggeon vertices
Abstract We demonstrate that a nonsense wrong signature zero is responsible for the vanishing of the triple Pomeron vertex with all legs at zero mass. The key input is the vanishing of certain fixed pole residues which is enforced by unitarity. Some other consequences of this general feature are drawn.
123029488
Dirichlet in all directions
Abstract This article enlarges on the theme of the workshop talk, which reviewed the non-perturbative structure of certain higher derivative terms in the type II string theory effective action and their connection to one-loop effects in eleven-dimensional supergravity compactified on a torus. Material is included that has appeared since the workshop.