# XRF

BACK

The XRF beamline is an experimental station dedicated to X-ray Fluorescence Microscopy (XRFM), X-ray Fluorescence Tomography (XFCT) and Total Reflection X-ray Fluorescence (TXRF) analysis in the hard X-rays energy range (5 to 20 keV). The beamline’s focus is on the determination and mapping of trace chemical elements in samples with applications in the fields of analytical chemistry, biomedicine, environmental geochemistry and materials science.

XRF’s source is a 1.67T bending magnet. The monochromator vacuum chamber can be laterally displaced, so that the whole synchrotron spectra can also be used to excite the samples. The experimental facilities include one station consisting of a high vacuum chamber in which grazing incidence x-ray fluorescence experiments can be carried out. The chamber is equipped with remote-controlled XY$latex \theta$y sample stages and a HPGe solid state detector, optimised for the detection of light element. The whole setup is mounted in the motorised lift table, which allows vertical positioning of the instruments on the plane where the incoming beam is mostly linearly polarized.

Applications include 2D XRF mapping and speciation of trace elements at 20 microns resolution, 3D information of elements in volumetric samples, analysis of very small masses deposited on flat substrate, trace impurities on surfaces of flat samples, chemical depth profiling surface analysis (from sub nm to mm range).

## CONTACT

Beamline Email: N/A

Beamline Telephone Number: +55 19 3512 1129

Coordinator: Carlos A. Pérez

Coordinator Email: carlos.perez@lnls.br

Coordinator Telephone Number: +55 19 3517 5081

For more information on the Beamline Team, check out the Beamline Team’s page here

# OPTICAL ELEMENTS

ElementTypePosition[m]Description
SOURCEBending Magnet0.0Bending Magnet D09 exit B (15°), 1.67 T , 0.92 mm x 0.57 mm
MonoDouble Crystal Monochromator11.2Si(111), Si(220), channel-cut type
M1Elliptical Vertical Micro- focusing Mirror14.9Rh coated, RT=334m (center), $\theta$=4 mrad
M2Elliptical Horizontal Microfocusing Mirror15.3Rh coated, RT=334m (center), $\theta$=4 mrad Rh coated, RT = 176m (center), $\theta$=4 mrad

# PARAMETERS

ParameterValueObs. | Condition
Energy range [keV]5-20Si(111) / Si(220)
Energy resolution [$\Delta$E/E]$10^{-4}$Si(111)
Beam size at sample [$\mu \rm m^{2}$, FWHM]22 x 12at 10 keV
Beam divergence at sample [$\rm mrad^{2}$, FWHM]10 x 1at 10 keV
Flux density at sample [ph/s/$\rm mm^{2}$/100 mA]$2 \times 10^{8}$at 10 keV
Flux density at focal spot [ph/s/100mA]$2 \times 10^{12}$White beam

# INSTRUMENTATION

InstrumentTypeModelSpecificationsManufacturer
DetectorSilicon driftAXAS-A$30 \rm mm^{2}$ SDD, FWHM $\leq$ 139eV at 5.9keVKETEK GmbH
DetectorSilicon driftAXAS-A$7 \rm mm^{2}$ SDD, FWHM $\leq$ 139eV at 5.9keVKETEK GmbH
DetectorHPGeGUL0035$30 \rm mm^{2}$ Ultra-LGe, FWHM = 140 eV at 5.9keVCanberra
CryostatCryostream Cooler700 SeriesMinimum of 173K, with a gas stability of 0.1KOxford

# CONTROL AND DATA ACQUISITION

All beamline controls are done through EPICS (Experimental Physics and Industrial Control System), running on a PXI from National Instruments. The data acquisition is done using a Red Hat workstation with the Py4Syn, developed at LNLS by SOL group. CSS (Control System Studio) are used as a graphical interface to display and control the beamline devices. Point-to-point or continuous scanning (“on-the-fly”) modes of operation can be used for data acquisition in 2D/3D experiments.

# APPLYING FOR BEAMTIME

Submission calls are usually announced twice per year, one for each semester. All the academic research proposals must be submitted electronically through the SAU Online portal. Learn more about how to submit a proposal here.