Pink-beam focusing with a one-dimensional compound refractive lens

Area of Science:

• X-ray optics
• Plasma physics
• Astrophysical simulation

Background:

• High-power X-ray beams are essential for simulating astrophysical environments.
• Focusing X-rays requires advanced optical components capable of handling high power densities.
• Compound refractive lenses (CRLs) offer potential for X-ray focusing but must be optimized for specific beam characteristics.

Purpose of the Study:

• To test the performance of a cooled Beryllium compound refractive lens (CRL) for vertical focusing of a pink X-ray beam.
• To enable spatial overlap of the focused X-ray beam with a simulated low-density astrophysical plasma.
• To achieve and measure high X-ray power densities for experimental applications.

Main Methods:

• Utilized a cooled Beryllium compound refractive lens (CRL) at the Advanced Photon Source (APS).
• Employed a two-chopper system to reduce power density for imaging.
• Developed a method to measure high power density and assess lens performance.
• Focused the fundamental harmonic of an insertion device white beam.

Main Results:

• The CRL enabled vertical focusing of the pink beam, achieving spatial overlap with the simulated plasma.
• Calculated X-ray power density reached up to 500 W/mm², demonstrating effective focusing.
• The experimental setup allowed imaging of the focal plane without X-ray filters due to power reduction.
• Confirmed the CRL's ability to focus the fundamental X-ray energy.

Conclusions:

• Cooled Beryllium CRLs are effective for focusing high-power X-ray beams for astrophysical simulations.
• The developed method allows for accurate measurement of high power densities and lens performance.
• This technique advances the capability to study high-energy density phenomena in laboratory settings.