# IMX

VOLTAR

## SOBRE A LINHA DE LUZ

The imaging beamline, IMX, at LNLS extracts synchrotron radiation from bending magnet D6 with magnetic field of 1.67 T and bending radius of 2.736 m. It has an electron source size of 391 $\mu$m x 97 $\mu$m and beam divergence of 808 $\mu$rad x 26 $\mu$rad and was designed to operate in either white beam or monochromatic beam. Monochromatic elements are Si(111) and a Ru/B4C Multilayer pair, located 12 m downstream from the source, and range in energy spectrums from 5 keV to 14 keV. Monochromatic elements can be removed from the beam to allow white light to enter the hutch. Pink beam energy spectrum ranges from 5 keV to 20 keV.

On entering the beamline, the beam is conditioned by white beam slits, before passing through a water-cooled Beryllium window (125 $\mu$m thick) positioned in front of the monochromator. Following this, the beam passes through the final Beryllium window which separates the vacuum from the air in the experimental hutch then, a small nitrogen filled ion chamber. The fast shutter controls the dosage on the sample, before the beam passes through a small vacuum section, provided by two Kapton windows (25 $\mu$m thick). A set of carefully optimised filters are available, which can be inserted into the beam path to remove low energies. These are particularly useful when imaging heavier or fragile samples where the lower energies either significantly damage the sample or result in beam hardening. The set consists of 4 highly polished Si filters of 200 and 350 $\mu$m thickness that can be combined to offset the average energy. Finally, a set of high precision slits defines the beam profile just before the sample.

The sample stage is located a few centimeters downstream of this set of slits. This stage allows for 2-dimensional translation (in the plane perpendicular to x-ray beam propagation) with sub-0.1 micron precision, to allow positioning of the sample within the x-ray beam, or to allow tiling of images. An air-bearing rotation stage, used for tomography scans, sits on the translation stage. Two high precision linear stages, mounted transversely to each other, allowing positioning of the sample over the axis of rotation. A magnetic sample mount is placed on top of the rotation stage, to locate the sample on the stage.

After passing through the sample, the X-rays pass through a thin vitrous carbon glass cover to enter a light-tight camera box. The x-rays reach a scintillator, which produces visible light; the local contact will select from one of 6 available scintillators; scintillator materials include Tb:LSO, LuAG, GGG, and Yag:Ce, of varying thicknesses, each optimized for work at different resolutions. Directly behind the scintillator is a mirror, set at a 45 degree angle. A turret containing long working distance lenses can then be used to image the scintillator onto a pco.2000 CCD camera. The objective is mounted on a stage which controls the image focus. The image recorded by the camera corresponds to a parallel projection of the sample onto the scintillator by the x-ray beam. In tomographic scans, a series of projection images are taken while the sample is usually rotated 180 degrees. The entire camera box move on two stages, which allows the sample-to-detector distance to be varied from a minimum of approximately 1 mm to a maximum of 300 mm and height to be adjusted given the monochromatic beam offset.

## CONTATO

Email da Linha de Luz: imx@lnls.br

Telefone da Linha de Luz: +55 19 3512 1142

Coordenador da Linha de Luz: Harry Westfahl Junior

Telefone do Coordenador: +55 19 3512 1045

Para mais informações sobre a equipe da Linha de Luz, confira a página da equipe aqui

# ELEMENTOS ÓTICOS

Elemento Tipo Posição[m] Descrição
SourceBending MagnetBending Magnet D06 exit B (15°), 1.67 T , 391 $\mu \rm m$ x 97 $\mu \rm m$
WindowBeryllium WindowPF1 125 $\mu \rm m$ thick
MonoDouble Multilayer Monochromator12Water-cooled Ru/B4C
MonoDouble Crystal Monochromator12Water-cooled Si(111)
WindowBeryllium WindowPF1 125 $\mu \rm m$ thick
FiltersXia Filter22Si(111) 200 $\mu \rm m$, 350 $\mu \rm m$

# PARÂMETROS

Parâmetro Valor Obs. | Condição
Energy range [keV]5 - 20Pink Beam
Energy range [keV]5 - 14Si(111) DCM / Multilayer DMM
Energy resolution [$\Delta$E/E]$1.3\times10^{-4}$Si(111)
Energy resolution [$\Delta$E/E]$1.4 \times 10^{-2}$Ru/B4C ML
Beam size at sample [$\mu \rm m^2$, FWHM]13 x 10Pink Beam
Beam size at sample [$\mu \rm m^2$, FWHM]13 x 4Si(111)/ML at 8keV
Beam divergence at sample [$\rm mrad^2$, FWHM]1 x 0.1at 8 keV
Flux density at sample [ph/s/$\rm mm^2$]$8.61 \times 10^{13}$Pink Beam
Flux density at sample [ph/s/$\rm mm^2$]$1.84 \times 10^{8}$Si(111) at 8 keV
Flux density at sample [ph/s/$\rm mm^2$]$1.22 \times 10^{10}$ML at 8 keV

# INSTRUMENTAÇÃO

Instrumento Tipo Modelo Especificações Fabricante
DetectorAreapco.20007.6 $\mu \rm m$ pixel, 2048 x 2048 pixel, 14-bit CCD cooled cameraPCO
MicroscopeOpticalLow-DoseMonochromatic microscope, 3 objectives in-line: x2, x4, x10Optique Peter
MicroscopeOpticalHigh-DoseWhite beam microscope, single objective: x5 or x10Optique Peter
ScintillatorHigh FluxLuAg:Ce$\phi\, 10\rm{mm}, 50 \mu \rm m$Crytur
ScintillatorHigh resolution, large field of viewLuAg:Ce$\phi\, 15\rm{mm}, 5\mu \rm m$Crytur
ScintillatorLow/medium fluxYag:Ce$\phi\,8\rm{mm}, 5 \mu \rm m$Crytur
ScintillatorHigh fluxYag:Ce 9x9mm, 50$\mu \rm m$Crytur
ScintillatorHigh resolutionTb:LSO$\phi\, 10 \rm{mm}, 8 \mu \rm m$FEE

# CONTROLE E AQUISIÇÃO DE DADOS

The LNLS X-Ray Imaging Beamline (IMX) uses a National Instruments PXI-6602 timing board attached to an NI PXI-1045 chassis to read digital counters and trigger devices during scans. A PiMicos UPR-160 rotation stage performs the sample rotation during tomography. The scan points are programmed directly on a Hydra SMC motion controller as a function of parameters passed from EPICS PV’s to reduce latency between scan points and enable quick tomography. The controller sends feedback through the I/O interface on trip-point arrival and transmits the present motion status, enabling hardware synchronization between motors and scan devices. A LabVIEW VI running on a dedicated Windows Machine controls a pco.2000 camera, which is currently the main detector at IMX Beamline. The user interface screens run from a workstation on CS-Studio environment under Linux Red Hat operational system. CS-Studio inputs integrate to EPICS via Py4Syn scripts to run scan routines and set up experiments.

Data visualization and analysis

IMX uses Avizo to visualize and analyze scientific and industrial 3D data acquired with X-ray imaging (IMX). Avizo is a powerful software application offering abundant state-of-the-art image data processing, exploration, and analysis features for understanding 3D images by extracting properties, statistics, models, and more from the original grayscale data. Learn more at www.Avizo3D.com.

# REQUISIÇÃO DE TEMPO DE FEIXE

Chamados de submissão de propostas são abertos usualmente duas vezes ao ano, um para cada semestre. Todas as propostas de pesquisa acadêmica precisam ser submetidas eletronicamente através do portal SAU Online. Saiba mais sobre o processo de submissão de propostas aqui.