Roberto Alvarez, Arizona State University
Abstract
Sample Delivery Advancements for Fluctuation X-ray Scattering
R. C. Alvarez1, A. Ansari, K. Karpos, J. M. Aguilar, S. Botha, J. P. J. Chen, A. A. Dev, D. Doppler, P. Fromme,
B. Hogue, H. Hu, D. Manatou, M. McFadden, B. R. Mobley, B. Nannenga, S. Saha, S. Sen, M. Sonker, M. F.
Brown, S. K. Menon, P. Konold, F. Maia, D. Westphal, T. V. Yenupuri, L. Pollack, A. Aquila, X. Cheng, D. P.
DePonte, G. Gate, M. S. Hunter, C. J. Kupitz, M Liang, S. Lisova, V. Mariani, S. Mous, D. J. Rosenberg, R. G.
Sierra, E. Schriber, T. D. Grant, and R. A. Kirian
1. Department of Physics, 550 E Tyler Drive, Tempe, Arizona 85287, USA.
Fluctuation X-Ray Scattering (FXS) [1] is direct 3D computational imaging that avoids cryogenic cooling or
crystallization of samples, and a priori modeling; however, the ultra-bright ultra-short pulses required [2]
have only recently been achieved through the advent of the X-ray Free Electron Laser. While the technique
has been validated [3,4], there has not yet been a convincing demonstration of FXS signals from proteins
that do not form large complexes (less than ~70 nm). We propose sparse photon signals could reduce the
largest sources of errors (detector artifacts and solution background) and overcome limits faced by
previous efforts. Here we present preliminary results from an experiment at the Light Coherent Light
Source to achieve sparse photon data through significant sample delivery improvements.
Acknowledgement
This work is supported by the National Science Foundation BioXFEL Science and Technology Center
(1231306), and National Science Foundation Awards 1817862 and 1943448.
References
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correlated fluctuations from snapshot small-angle x-ray scattering. Phys. Rev. E 84, (2011).
3. Kurta, R. P. et al. Correlations in Scattered X-Ray Laser Pulses Reveal Nanoscale Structural Features of
Viruses. Phys. Rev. Lett. 119, (2017).
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