![P373 - Monochromator - Large angle plane grating monochromator (PGM) for soft X-ray synchrotron radiation - BL5 beamline at synchrotron radiation source SSRL, USA - Bestec GmbH P373 - Large angle plane grating monochromator (PGM) for soft X-ray synchrotron radiation - BL5 beamline at synchrotron radiation source SSRL, USA - Bestec GmbH](https://bestec-depos.com/wp-content/uploads/2019/02/P373-Monochromator-Bestec-GmbH_02-853x1024.png)
P373 – VLS-PGM BL5 SSRL
Application
Large angle plane grating monochromator (PGM) for soft X-ray synchrotron radiation
Year of delivery
2013
Installation site
BL5 beamline at synchrotron radiation source SSRL, USA
Design Features
-
High-resolution large-angle grazing incidence variable line spacing plane grating monochromator (VLS-PGM).
- Spectral range: 25 – 200 eV.
- Optical elements: one plane mirror and three VLS plane gratings.
- Temperature sensors at internal mechanics, at mirror and gratings chin guards, at mirror and grating substrates.
-
Active water cooling of the mirror, passive cooling of the gratings.
- Four indirectly cooled OFHC aperture blades at the PGM exit flange; motorized and encoded independent translation of the vertically defining blades.
-
Water cooled zero-order stop.
-
Motion control system with EPICS interface.
- Permanently installed bakeout provisions.
- Adjustable support structure.
Performance Features
- High positioning resolution (minimum incremental motion).
- High pitch rotation stability and repeatability.
- Minimized mounting induced deformations.
Outer Dimensions
Technical specifications and performance values
General
Vacuum chamber
Chamber type
cylindrical, vertical axis
Main flanges
at the top
Material
1.4404 (C < 0.02%)
Base pressure
10-10 mbar range
Optical design parameters
Beam height (entrance)
1071 mm
Beam offset
25 mm
Number of plane mirrors
1
Plane mirror dimensions
280 mm x 50 mm x 50 mm
Number of gratings
1
Gratings dimensions
60 mm x 30 mm x 23 mm
100 mm x 30 mm x 23 mm
150 mm x 30 mm x 23 mm
Support structure
Adjustment ranges
Vertical translation
± 10 mm
Lateral translation
± 10 mm
Longitudinal translation
± 10 mm
Pitch
± 1°
Roll
± 1°
Yaw
± 1°
Plane mirror
Pitch rotation
Range
-1.17° to +27.35°
Resolution (design value)
0.004 µrad /motor fine step
(1/64, recommended)
0.0097087 µrad /encoder count
Resolution (measured value)
0.10 µrad
Repeatability
0.21 µrad (pitch)
0.18 µrad (roll)
Long-term stability (>10h)
0.03 µrad
Stability (2 l /min cooling water)
<0.05 µrad
Translation
Range
55 mm
Resolution (design value)
0.03 µm /motor fine step
(1/512, recommended)
0.05 µm /encoder count
Repeatability
0.20 µrad (pitch)
0.18 µrad (roll)
Gratings
Pitch rotation
Range
-1.16° to +31.32°
Resolution (design value)
0.004 µrad /motor fine step
(1/64, recommended)
0.0097087 µrad /encoder count
Resolution (measured value)
0.10 µrad
Repeatability
0.15 µrad (pitch)
0.25 µrad (roll)
Long-term stability (>2h)
0.04 µrad
Stability (2 l /min cooling water)
< 0.065 µrad
Translation
Range
159.15 mm
Resolution (design value)
0.02 µm /motor fine step
(1/512, recommended)
0.05 µm /encoder count
Repeatability
0.13 µrad (pitch)
0.24 µrad (roll)
Aperture unit
Blades
Material
OFHC
Range
-5 mm to + 10 mm
Resolution (design value)
10 µm /step (full step)