In situ small-angle X-ray scattering characterization of X-ray-induced local heating

It is shown that small-angle X-ray scattering from binary liquid mixtures close to the critical point of demixing can be used for in situ characterization of beam-induced heating of liquid samples. For demonstration purposes, the proposed approach is applied on a well studied critical mixture of water and 2,6-lutidine. Given a typical incident X-ray flux at a third-generation synchrotron light source and using a 1.5 mm-diameter glass capillary as sample container, a beam-induced local temperature increase of 0.45 ± 0.10 K is observed.