title: Expected thermal deformation and wavefront preservation of a cryogenic Si monochromator for Cornell ERL beamlines.
abstract: Cornell energy-recovery linac (ERL) beamlines will have higher power density and higher fractional coherence than those available at third-generation sources; therefore the capability of a monochromator for ERL beamlines has to be studied. A cryogenic Si monochromator is considered in this paper because the perfect atomic structure of Si crystal is needed to deliver highly coherent radiation. Since neither the total heat load nor the power density alone can determine the severity of crystal deformation, a metric called modified linear power density is used to gauge the thermal deformation. For all ERL undulator beamlines, crystal thermal deformation profiles are simulated using the finite-element analysis tool ANSYS, and wavefront propagations are simulated using Synchrotron Radiation Workshop. It is concluded that cryogenic Si monochromators will be suitable for ERL beamlines in general.
authors.affiliation: Cornell High Energy Synchrotron Source, Cornell University, 161 Synchrotron Drive, Ithaca, NY 14853, USA.
authors.forename: Rong
authors.initials: R
authors.lastname: Huang
authors.affiliation: Cornell High Energy Synchrotron Source, Cornell University, 161 Synchrotron Drive, Ithaca, NY 14853, USA.
authors.forename: Donald H
authors.initials: DH
authors.lastname: Bilderback
authors.affiliation: Cornell High Energy Synchrotron Source, Cornell University, 161 Synchrotron Drive, Ithaca, NY 14853, USA.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Finkelstein
mesh_terms: D003460:Crystallization; D020342:Finite Element Analysis; D006358:Hot Temperature; D055595:Mechanical Phenomena; D012825:Silicon / Q000737:chemistry; D017356:Synchrotrons / Q000295:instrumentation
chemical_list: D012825:Silicon
keywords: X-ray optics; cryogenic monochromator; crystal thermal deformation; energy-recovery linac; wavefront preservation