| Paper | Title | Page |
|---|
| WEP02 | Superconducting RF Photocathode Gun for Low Emittance Polarized Electron Beams | 434 |
| | - D. Holmes, H. Bluem, B. Abel, A. Favale, E. Peterson, J. Rathke, T. Schultheiss, A. Todd
Advanced Energy Systems, Inc. - J. Kewisch, I. Ben-Zvi, A. Burrill, R. Grover, D. Pate, T. Rao, R. Todd
Brookhaven National Laboratory
| |
| | The use of an RF electron gun with a magnetized
cathode in place of a DC gun for ILC may eliminate the
need for emittance damping rings. So far only DC guns
have been used to provide polarized electron beams
because of the very high vacuum level needed for
survival of the Gallium Arsenide (GaAs) cathode
material used to generate polarized electrons.
Maintaining adequate lifetime of GaAs cathode material
requires vacuum levels in the 10-11 torr range. While
vacuum levels around the 10-9 torr range are common in a
normal conducting RF gun, the cryogenic pumping of the
cavity walls of a superconducting RF (SRF) gun may
maintain vacuum in the range needed for GaAs cathode
longevity.
Advanced Energy Systems, Inc. is collaborating with
Brookhaven National Laboratory to investigate the
generation of polarized electron beams using a SRF
photocathode gun. The team is developing an
experiment to study the quantum lifetime of a GaAs
cathode in a SRF cavity and investigate long term cavity
performance while integrated with a cesiated GaAs
cathode [1]. This paper reviews the design and analysis
performed to develop a method to prepare and install
GaAs cathodes into a SRF cavity in support of this
experiment. | |
| WEP37 | Nondistructive testing instrument of dished Nb sheets for SRF cavities based on squid technology | 562 |
| | - Q. S. Shu, J. Susta, G. F. Cheng, I. Phipps
AMAC Inc - R. Selim, J. Mast
Christopher Newport University - P. Kneisel, G. Myneni
JLab - I. Ben-Zvi
Brookhaven National Lab
| |
| | The performance of superconducting RF cavities used in
accelerators can be enhanced by detecting micro particles
and inclusions which are the most serious source of
performance degradation. These defects prevent the
cavities from reaching the highest possible accelerating
fields. We have developed a SQUID scanning system
based on eddy current technique that allows the scanning
of curved Nb samples. This SQUID scanning system
successfully located Tantalum defects about 100 um
diameter in a flat Nb sample and was able to also locate
the defects in a cylindrical surface sample. Most
importantly, however, the system successfully located the
defects on the backside of the flat sample and curved
sample, both 3-mm thick. This system can be used for the
inspection and detection of such defects during SRF
cavity manufacturing. | |
| FR101 | Electron cooling and electron-ion colliders at BNL | 740 |
| | - I. Ben-Zvi
Brookhaven National Laboratory
| |
| | Superconducting Energy Recovery Linacs (ERL) have
significant potential uses in various fields, including High
Energy Physics and Nuclear Physics. Brookhaven
National Laboratory (BNL) is pursuing some of the
potential applications in this area and the technology
issues that are associated with these applications.
The work addressed in this paper is carried out at BNL
towards applications in electron cooling of high-energy
hadron beams and electron-nucleon colliders. The
common issues for these applications are the generation
of high currents of polarized or high-brightness
unpolarized electrons, high-charge per bunch and highcurrent.
One must address the associated issue of High-
Order Modes generation and damping. Superconducting
ERLs have great advantages for these applications as will
be outlined in the text. | |
 | Slides(PDF) | |