Ultra-Small-Angle X-ray Scattering Facility


Ultra-Small-Angle, Small-Angle, and Diffraction (Wide-Angle) X-ray Scattering  

Instrument will be commissioning during early Fall and may be available to GU users from November. 

Proposal deadline is June 28, 2024. 

There is new proposal system, read about it here: 

The USAXS/SAXS/WAXS facility offers world-unique capabilities to users in physics, chemistry, materials science, polymers, food science, biology, and many others. Data are measured over about: 

  • 5 decades in sizes - from approximately 6 microns to less than 1 Angstrom
  • Intensity range of up to 12 decades
  • About 3 minutes data collection time.

This is achieved by combination of Bonse-Hart USAXS device, combined with 500mm long pinhole SAXS and 300mm long area detector based diffraction (WAXS) device. See some example data in graphics below on this page.

Contact instrument scientist: Jan Ilavsky, 630-252-0866. 

Important :

Data are collected sequentially using one or more of our devices. USAXS use is required.
Typical USAXS beam size is 0.8 x 0.8 mm. Beam size is flexible between 1 x 1 mm to 0.2 x 0.2 mm. Smaller beam sizes require stronger scattering systems.
Standard SAXS/WAXS beam size is 0.8 x 0.2 mm and can be as small as 0.2 x 0.2 mm. Smaller beam sizes require longer exposure times.
Typical combined data collection time is <3 minutes for USAXS/SAXS/WAXS
     USAXS data collection time is 60-120 sec (typical ~ 90s),
     SAXS & WAXS is 1 - 15 sec each (typical ~ 2 sec SAXS, 15 sec WAXS).
This device sensitivity is limited by Bonse-Hart crystal surface background and we cannot measure really weak signals, such as common in bioSAXS (proteins) or very dilute systems. Talk to staff to evaluate in this facility is appropriate for your problem.

Want to see how USAXS operates? 3 min (166Mb) movie with data collection is here: USAXS_operations.mp4

Current instrument paperIlavsky, J., Zhang, F., et al. (2018). "Development of combined microstructure and structure characterization facility for in situ and operando studies at the Advanced Photon Source." Journal Of Applied Crystallography 51, 867-882. https://doi.org/10.1107/S160057671800643X

USAXS newsletter subscribe/unsubscribe web page


  1. General User (GU) program (~ 80% of beamtime, see "All about proposals here").  
  2. Mail in program: We make available about 2-3 days of beamtime per cycle to users, who have smaller sets of samples (typically less than 20 samples). Typical use is exploratory research (before applying for beamtime) or when project requires limited number of samples. No beamtime proposal is necessary and users cannot come for experiments to the APS. Samples will be handled by USAXS staff and reduced data will be sent back to users. For details see dedicated page
  3. Proprietary (industrial) research is available as part of GU program. Contact staff and APS users office, start here
  4. We also support SAXS-SANS collaboration mail-in program. Contact staff.

If you want to apply for beamtime through any method, contact staff to discuss your need and suitability of the project for this instrument. For methods 2-4 you MUST talk to staff first

Examples of USAXS results for general public:

2018 additive manufacturing USAXS science highlight

2019 Story about USAXS in chocolate science (APS version) (Confectionerynews version)

2020 APS Scientific highlight (Pickering Emulsions)

2021 APS Scientific highlight (Colloidal gels)

Typical parameters are below:

Standard USAXS configuration (Si 220 crystals, slit smeared) - default

  • Energy range ............    12 - 30 keV, typical 21keV
  • Q range combined ....    8*10-5 to 6 [A-1]
  • Q resolution USAXS ..   8*10-5 [A-1] in the USAXS range (up to ~0.1 [A-1])
  • Size range comb........    6 micron - 1 Angstrom
  • Collection time comb..    <3 minutes
  • Intensity range ...........   up to 12 decades (depends on sample), desmeared 
  • SAXS Q range ...........  ~ 0.03 to 1.3 [A-1]
  • WAXS Q range ..........  ~ 0.8   to  6 [A-1]

High resolution USAXS configuration (Si 440 crystals, slit smeared) in 2025, on request

  • Energy .......................   21 - 30 keV,  24keV typical
  • Q range combined ....    3*10-5 to 6 [A-1]
  • Q resolution USAXS...   3*10-5 [A-1] in the USAXS range (up to ~0.1 [A-1])
  • Size range comb........    20 micron - 1 Angstrom
  • Collection time comb..    <3 minutes
  • Intensity range ...........    up to 12 decades (depends on sample), desmeared
  • SAXS Q range ...........   ~ 0.03 to 1.3 [A-1]
  • WAXS Q range ..........   ~ 0.8   to  6 [A-1]

2D collimated USAXS (Si 220 crystals) - not available until after APS upgrade (~2025)

  • Energy ....................  12 - 21 keV
  • Q range ..................   8*10-5 [A-1] to 0.1 [A-1
  • Collection time ........  4 - 6 minutes
  • Intensity range ........  up to 8 decades (depends on sample)
  • Q resolution ............  3*10-5 [A-1] in the USAXS range (up to ~0.1 [A-1])
  • SAXS ....................... not available
  • WAXS ...................... not available

USAXS Imaging - not available until after APS upgrade (~2025)

Graph of results and schematics:

1D Usaxs

Schematics of USAXS instrument at 12IDE - top view. For illustration only, NOT for publications. For latest updated drawing please contact beamline scientist.

Usaxs Saxs Waxs

Schematics of the USAXS - SAXS - WAXS instrument (top view) with all three geometries. Data are collected sequentially using the three devices. Change over time between detectors is about 30 seconds.

E15 Movie

An in-situ USAXS-SAXS-WAXS study of precipitate dissolution and size evolution in a model gamma-gamma Prime ternary Ni-based alloy (collaboration with Dr. G. Muralidharan, ORNL). A 0.1 mm thick sample was heated from RT to 1100C at 4.5C/min while undergoing repeated USAXS-SAXS-WAXS (24 keV) at 5 minute intervals. Research sponsored by the U.S. Department of Energy, Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies, as part of the Propulsion Materials Program.

Annealing Al Alloy

USAXS/SAXS/WAXS data : In situ data collected at 226 °C over about 16 hours represent microstructure evolution of AA2024 aluminum alloy (Allen, Levine, and Zhang, NIST). USAXS data enable quantification of second phase formation (size and volume), WAXS enables phase identification.

Sio2 Scattering

Scattering of 1 micron SiO2 spheres in aqueous solution.

Annealing High Exposives

USAXS/SAXS/WAXS in situ data : Data collected by LLNL (Trevor Willey et.al.) on high-explosives. The material is composite of two high-explosives and plastic binder. The WAXS clearly shows phase changes while USAXS/SAXS data show microstructure change as function of heating.

1.0um Usaxs

Scattering of 1 micron Polystyrene spheres in solution.