Comparison of planar helical undulator designs for spear beamline five

Technical Report · Fri Jan 01 04:00:00 EST 1993

DOI:https://doi.org/10.2172/6731595· OSTI ID:6731595

Carr, R

There is an increasing demand for circularly polarized soft x-rays in the study of magnetic materials, biological molecules, and other systems that exhibit circular dichroism. At present, most experiments have been done with bending magnet radiation that is circularly polarized above and below the horizontal midplane of the storage ring. A number of insertion devices generate elliptically polarized x-rays, such as bifilar solenoids, elliptical and asymmetric wigglers, crossed undulators, and planar helical undulators. Elliptically polarized light is generated when electrons enter a helical magnetic field; the helicity of the field determines the helicity of the x-ray emission. Among the various technologies, the pure permanent magnet planar helical undulator is probably the best choice for installation on BLV in summer, 1993. This approach was pioneered by Pascal Elleaume at ESRF; he has installed a device of this type called 'Helios'. Richard Walker and Shigemi Sasaki have developed alternative planar helical undulators, which improve on the basic design of Elleaume. This proposal is a discussion of planar helical undulator strategies from which implementation choices can be made. We will consider only pure RCP and LCP sources, since we are trying only to span the range from 500--1000 eV. If we needed a broader range, we might consider creating elliptically polarized light, and hence, harmonics which RCP and LCP sources do not have.

• Research Organization: Stanford Linear Accelerator Center, Menlo Park, CA (United States)
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC03-76SF00515
• OSTI ID: 6731595
• Report Number(s): SLAC-TN-93-2; SLAC/SSRL--0002; ON: DE93009082
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
430303* -- Particle Accelerators-- Experimental Facilities & Equipment
BEAM BENDING MAGNETS
COMPARATIVE EVALUATIONS
DESIGN
ELECTRICAL EQUIPMENT
ELECTROMAGNETIC RADIATION
ELECTROMAGNETS
EQUIPMENT
EVALUATION
IONIZING RADIATIONS
MAGNETIC FIELDS
MAGNETS
MONOCHROMATORS
RADIATIONS
WIGGLER MAGNETS
X RADIATION