X-ray Fluorescence Imaging
X-ray fluorescence imaging utilizes the high brightness of SPEAR3 and focused beam generated by the uses of K-B optics, capillaries and apertures to study spatial distribution of elements in biological samples such as brain tissue. The imaging beam lines have the unique capability of combining spatial mapping with chemical and structural information of various elements through XAS (edges and EXAFS). The three beam lines are equipped with standardized instrumentation for seamless measurement across 2-30 eV energy range and 2-250 µm length scales.
Beam Line 2-3
BL2-3 is a dedicated micro-XAS bending magnet beam line with a pair of Kirkpatrick-Baez (KB) Pt coated mirrors as the focusing optics to achieve a spot size of 2 µm2. The only optical element in front of the experimental hutch is a water-cooled variable-exit monochromator. The presence of minimal optical elements upstream of the experimental focusing optics imparts exceptional spatial stability to the micro-focused spot. Experiments conducted on this beam line include XRF imaging, micro-XAS (both XANES and EXAFS), XANES imaging, micro-diffraction and fluorescence tomography.
Beam Line 10-2a
BL10-2a is high flux wiggler beamline dedicated to large format (600 x 300 mm) XAS imaging. A combination of capillary optics and pinhole apertures are used to achieve beam sizes from ~10 to 250 µm2. The higher flux on beamline 10-2b (~10-50 times greater than BL 2-3) provides a complementary set of abilities to BL 2-3, such as rapid scanning over larger areas and the ability to detect lower elemental concentrations. Experiments conducted on this beam line include XRF imaging, micro-XAS (both XANES and EXAFS) and XANES imaging.
Beam Line 14-3b
Beam line 14-3b is a bending magnet side station dedicated to X-ray imaging and micro X-ray absorption spectroscopy of biological, biomedical, materials, and geological samples. 14-3b is equipped with specialized instrumentation for XRF imaging data collection in the tender X-ray regime of 2-5 KeV. A Kirkpatrick-Baez (KB) mirror system is used to achieve microfocus beam of ~ 5 µm2. BL14-3b is ideal for obtaining elemental maps of small samples (~ 20 µm to 25 mm) as well as performing XANES on selected points in the sample (~5 µm2). Experiments conducted on this beam line include XRF imaging, micro-XAS and XANES imaging.
Support
The SSRL SMB group is directly responsible for the maintenance and operation of the XRF imaging experimental station of beam lines 2-3, 14-3b and 10-2a. User support is provided at the technical, engineering and scientific level of data acquisition and analysis by experienced staff personnel.