摘要:

A linear accelerator is now in use which increases the energy of protons from a 4‐Mev Van de Graaff injector to a final energy of 31.5 Mev. The accelerator consists of a cavity 40 feet long and 39 inches in diameter, excited at resonance in a longitudinal electric mode with a radio‐frequency power of about 2.1×106watts peak at 202.5 Mc. Acceleration is made possible by the introduction of 46 axial ``drift tubes'' into the cavity, which is designed so that the particles traverse the distance between the centers of successive tubes in one cycle of the rf power. The proton bunches are longitudinally stable as in the synchrotron, and are stabilized transversely by the action of converging fields produced by focusing grids. The electrical cavity is constructed like an inverted airplane fuselage and is supported in a vacuum tank. Power is supplied by 9 high‐powered oscillators fed from a pulse generator of the artificial transmission line type. Output currents are 3×10−7ampere, average, and 60 &mgr;a, peak. The beam has a diameter of 1 cm and an angular divergence of 10−3radian.

ISSN:0034-6748    

DOI:10.1063/1.1771253

出版商:AIP    

年代:1955

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1771254

出版商:AIP    

年代:1955

数据来源: AIP

摘要:

The development of the Mark II electron linear accelerator, the second linear accelerator constructed at Stanford University, is described. Primarily intended to provide an intermediate milepost on the way toward the eventual construction of a 1‐Bev machine, it was designed to be a prototype of one of the many sections of the larger accelerator. Electron energies up to nearly 40 Mev have been obtained, and peak beam currents of about 10 ma in 1‐&mgr;sec pulses. The theoretical design and experimental testing procedures developed in constructing the loaded wave guide are outlined. A brief description of the auxiliary equipment, including a multi‐megawatt klystron amplifier, is given. Operating characteristics of the accelerator are summarized. The machine has been in use since 1950 for experimentation in electron physics.

ISSN:0034-6748    

DOI:10.1063/1.1771255

出版商:AIP    

年代:1955

数据来源: AIP

摘要:

The Bevatron requires an intense source of high‐energy protons. The machine should accept monoenergetic protons for a duration of approximately 500 microseconds once every 6 seconds. To satisfy the requirements of small loss due to scattering by the gas in the accelerating chamber, a 9.9‐Mev linear accelerator has been built and operated.A 500‐kilovolt Cockcroft‐Walton generator is used to inject 3‐ma peak proton current into the linear accelerator. Focusing grids intercept approximately half of the injected beam. Additional losses, including radial defocusing and acceptance phase angle, result in a peak accelerated beam of 225 microamperes. The energy spread of the accelerated protons has not been measured, but an upper limit is less than ±30 kev.

ISSN:0034-6748    

DOI:10.1063/1.1771256

出版商:AIP    

年代:1955

数据来源: AIP

摘要:

The results of the investigation of three methods of obtaining transverse stability in linear accelerators for ions are presented and discussed. For electric or magnetic quadrupole focusing the range of stable operation, oscillation amplitudes, and the effect of perturbing errors are treated. For grid focusing, the operation of an actual grid is analyzed from measurements of the field distribution. Finally, the formulas applicable to focusing by axial magnetic lenses are presented.

ISSN:0034-6748    

DOI:10.1063/1.1771257

出版商:AIP    

年代:1955

数据来源: AIP

摘要:

A monitor for high‐energy beams of charged particles utilizing the phenomenon of secondary emission is described. The primary beam to be monitored passes through a set of foils alternately phased in voltage. The current produced by secondary electrons ejected by the beam passage is collected onto the one set of foils and measured. Results of tests with high‐energy electrons are given. The monitor gives no indication of saturation up to peak current densities of 16 ma/cm2, and is independent of the primary beam energy in the range over which the monitor was tested (111–235 Mev).

ISSN:0034-6748    

DOI:10.1063/1.1771258

出版商:AIP    

年代:1955

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1771259

出版商:AIP    

年代:1955

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1771262

出版商:AIP    

年代:1955

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1771263

出版商:AIP    

年代:1955

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1771264

出版商:AIP    

年代:1955

数据来源: AIP