ID10A - Troika I+III Beamline
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Synopsis
The ID10A beamline is a multi-purpose, high-brilliance undulator beamline for high resolution X-ray scattering (XD) and X-ray photon correlation spectroscopy (XPCS) experiments. It is an independent branch of the TROIKA beamline and comprises two experimental stations: TROIKA I and TROIKA III. The TROIKA I station is mainly dedicated to XD and XPCS at large momentum transfers including scattering from liquids. TROIKA III is specialized for Small-angle Scattering (SAXS) experiments with coherent X-rays. Scientific applications cover studies of the structural and dynamic properties of soft and hard condensed matter materials (see also the ID10A science page).
The main features of the beamline are:
TROIKA I:
- High-resolution instrumentation for horizontal and vertical scattering geometries (SAXS to WAXS)
- Possibility of grazing incidence scattering from liquid surfaces
- Large energy-tunability (7 keV < E < 20 keV)
- Three single-bounce monochromators: Si(111), diamond (111), diamond (220)
(intrinsic energy resolution: 0.2*10-4 <E/E < 1.4*10-4)
- High coherent flux (> 109 ph/sec/100mA in a 10x10 µm2 beamspot,
E/E = 1.4*10-4)
- Spezialized for X-ray photon correlation spectroscopy (XPCS) experiments (7 keV < E < 13 keV)
TROIKA III:
- Optimized for coherent small-angle X-ray scattering (SAXS) and XPCS (7 keV < E < 20 keV)
- High coherent flux: > 109 ph/sec/100mA in a 10x10 µm2 beamspot (
E/E = 1.4*10-4)
- "Pink" beam option (
E/E = 1-3%)
- "White" beam option
Scientific Applications
X-ray scattering can give information on the time-averaged structure of materials. The combination of small-angle (SAXS) and wide-angle (WAXS) scattering allows to cover length scales from several thousand Angstroms (Q ~ 10-3 Å-1) down to atomic resolution (Q ~ 1 Å-1). Coherent X-rays and the technique of X-ray photon correlation spectrsocopy (XPCS) allows the study of slow equilibrium- and non-equilibrium dynamics in disordered or modulated materials on timescales beyond the reach of the inelastic (X-ray or neutron) techniques. XPCS is complementary to dynamic light scattering (DLS) and typically covers a time window of 10-8 s < t < 1000 s. Among the applications are:
- Dynamics of colloidal and polymer systems
- Domain-formation and dynamics in phase separating systems
- Dynamics of glass forming systems
- Critical dynamics
- Surface, capillary wave and membrane dynamics
The XPCS technique in SAXS or WAXS geometry implies the capability for time-averaged scattering experiments. Hence the beamline can cover every potential demand for high resolution diffraction including anomalous and magnetic X-ray scattering.
Techniques Available
High-resolution Wide-angle Scattering (WAXS)
A versatile 4/6 circle diffractometer at TROIKA I with variable resolution set-up on the detector side (slits and crystal analysers) together with the wide energy tunability and variable energy resolution permits virtually every diffraction experiment in horizontal or vertical scattering geometry.
Small-angle X-ray Scattering (SAXS)
A temperature controlled SAXS chamber supporting samples in glass-capillaries or flat containers is available at both TROIKA I and TROIKA III. SAXS profile can be taken with either a 0-D detector or a 2-D CCD detector. The setup is optimized for dynamic XPCS experiments employing a coherent X-ray beam and not for high through-put SAXS data aquisition.
Surface Scattering Techniques
The TROIKA I instrumentation is comaptible with Grazing-incidence (GID) and Grazing-incidence Samll-angle scattering (GISAXS) geometries in horizontal or vertical scattering geometry allowing in particular also experiments on liquid surfaces.
X-ray Photon Correlation Spectroscopy (XPCS)
Monochromatic (E/E = 1.4*10-4 ) coherent X-rays (typical beamsize 10x10 µm2 , 8 keV) is available at TROIKA I and TROIKA III. Time-correlation functions are recorded with help of a digital autocorrelator (0D) or by software (2D).