title: Soft X-ray radiation-damage studies in PMMA using a cryo-STXM.
abstract: Radiation damage sets a fundamental limit for studies with ionizing radiation; cryo-methods are known to ease these limits. Here, measurements on mass loss and the decrease in the C=O bond density as measured by oxygen-edge XANES (NEXAFS) spectroscopy in thin films of poly(methylmethacrylate) (PMMA), studied in a vacuum, are reported. While cryo-methods allow more than 95% of the mass to remain at doses up to 10(7) Gy, there is little difference in C=O bond density versus dose between 298 K and 113 K sample temperatures. At both temperatures the critical dose for bond breaking is approximately 15 x 10(6) Gy.
authors.affiliation: Department of Physics and Astronomy, SUNY Stony Brook, NY 11794-3800, USA. tobias.beetz@stonybrook.edu
authors.forename: Tobias
authors.initials: T
authors.lastname: Beetz
authors.forename: Chris
authors.initials: C
authors.lastname: Jacobsen
mesh_terms: D018360:Crystallography, X-Ray / Q000379:methods*; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D012867:Skin / Q000528:radiation effects*; D017356:Synchrotrons
chemical_list: D019904:Polymethyl Methacrylate