title: Pink-beam focusing with a one-dimensional compound refractive lens.
abstract: The performance of a cooled Be compound refractive lens (CRL) has been tested at the Advanced Photon Source (APS) to enable vertical focusing of the pink beam and permit the X-ray beam to spatially overlap with an 80 µm-high low-density plasma that simulates astrophysical environments. Focusing the fundamental harmonics of an insertion device white beam increases the APS power density; here, a power density as high as 500 W mm(-2) was calculated. A CRL is chromatic so it does not efficiently focus X-rays whose energies are above the fundamental. Only the fundamental of the undulator focuses at the experiment. A two-chopper system reduces the power density on the imaging system and lens by four orders of magnitude, enabling imaging of the focal plane without any X-ray filter. A method to measure such high power density as well as the performance of the lens in focusing the pink beam is reported.
authors: Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA.
authors: Eric M
authors: EM
authors: Dufresne
authors: Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA.
authors: Robert W
authors: RW
authors: Dunford
authors: Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA.
authors: Elliot P
authors: EP
authors: Kanter
authors: Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA.
authors: Yuan
authors: Y
authors: Gao
authors: Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA.
authors: Seoksu
authors: S
authors: Moon
authors: Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA.
authors: Donald A
authors: DA
authors: Walko
authors: Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA.
authors: Xusheng
authors: X
authors: Zhang
keywords: chromatic aberration; compound refractive lenses; pink beam