The Coherent Hard X-ray (CHX) beamline at NSLS-II is a synchrotron undulator-based instrument dedicated to nanometer-scale dynamics. It sits at beamport 11-ID. The instrument is primarily focused on enabling XPCS (X-ray Photon Correlation Spectroscopy) measurements of speckle fluctuation; measurement of the time correlation function can be used to quantify dynamics. Due to the high coherent brightness of the NSLS-II storage ring, CHX will enable measurements over timescales previously inaccessible.
Although CHX is focused on XPCS, it is also capable of exploiting its high beam coherence in other ways, such as coherent scattering or CDI. Additionally, the beamline is capable of more traditional scattering experiments, such as SAXS and WAXS.
CHX can perform a variety of experiments:
- Coherent scattering
- All of these experiments can also be performed in grazing-incidence mode (GISAXS/GIWAXS, etc.).
- Can perform experiments from 6 keV to 16 keV.
- Energy resolution (double crystal monochromator): 10−4
At sample position:
- 5 ×1011 ph/s/0.01%bw (9 keV, 15 µm beam)
- Unfocused beam sizes ~200 µm
- Focusing (H and V) available to ~10 µm (ultimate goal ~2 µm)
CHX is a high-coherence beamline. It will ultimately deliver fully coherent beams.
CHX is currently commissioning. Access is available through the NSLS-II proposal system. Interested users should contact beamline staff.