Presentation on theme: "P4 Shutter Review May, 2005 P4 – ID Movable Beam Stop and Integral Shutters Presented by K. Beyer and T. Lutes."— Presentation transcript:
P4 Shutter Review May, 2005 P4 – ID Movable Beam Stop and Integral Shutters Presented by K. Beyer and T. Lutes
Acknowledgements Thanks to the following people for contributing reference information APS Staff Mohan Ramanathan Deming Shu P.K. Job
P4 Shutter: Features There are nine (9) P4 shutters at the APS as of May 2005. All have the ability to stop Insertion Device (ID) White Beam, or let it pass downstream When passing White beam through the shutter, Bremsstrahlung radiation is collimated by a tungsten stop with an aperture
P4-20 Internal components (1) Movable, glid-cop/copper, water cooled, white beam stop (also used in the P2 shutter) Stopping power ~ 6,000 Watts Incidence angle = 2.5° (2) Movable monochromatic beam stops Stopping power ~ 10 Watts (1) Movable tungsten safety stop/collimator Aperture = 18 mm (h) x 80 mm (w)
P4-20 Shutter Side View Mono-shutter Assemblies White Beam Stop (Incidence angle = 2.5°) Bremsstrahlung collimator (18 mm x 80 mm) Vacuum pump port Position sensor port (never implemented) Mono- beam White beam
P4-20 Shutter Mode Keys White Beam Stop lock and pin Mono- Beam Stop lock and pin Safety Stop lock and pin
P4-20 : White Beam Mode Mono Shutter key secured in cylinder lock White Beam Stop key secured in PSS panel Safety Shutter key secured in PSS panel White beam passes above the absorber and travels through the collimator. Bremsstrahlung radiation is collimated via the 80 mm x 18 mm aperture.
P4-20 : Bremsstrahlung Collimation White beam and Bremsstrahlung impinge on the aperture The small White beam spot passes completely through the aperture Bremsstrahlung radiation is collimated (constrained) by the 18 mm x 80 mm opening In White beam Mode, the shutter acts like a beam transport tube with a Bremsstrahlung collimator inside
P4-20 : Mono- Beam Mode P4 Mono Shutter key secured in PSS panel P4 White Beam Stop key secured in cylinder lock P4 Safety Shutter key secured in cylinder lock White beam is intercepted by the absorber and stops. Bremsstrahlung radiation is stopped by the tungsten in the collimator block.
P4 Shutter Modifications The P4 shutter evolved as a result of several factors: Experience Discussion with other beamlines who were using previous versions of the device Complexity Desire for the elimination of mode changes Cost Fabrication of certain pieces was expensive Flexibility Sometimes used as a Mono- shutter (with the desire for White beam use in the future)
P4-30 : Shutter Side View White Beam Stop (Incidence angle = 3°) Bremsstrahlung collimator (14 mm x 16 mm)
P4-30 : 4-ID-A No mode change White beam absorber is redundant to FE Shutter (PS2) Standard S3-30 collimator follows White beam absorber In 4-ID-A there are 2 mirrors upstream of the P4-30 that need to be kept warm. This device is like having a second PS2.
P4-30 : White Beam Absorber When the absorber is down (shutter closed), the White beam intercepts the walls (3° incident angle) and is stopped. When the absorber is up (shutter open), the aperture aligns with the White beam and allows it to pass through. Aperture = 5.5 mm x 5.5 mm
P4-39 : White Beam Absorber The White beam absorber has been modified such that it can accept photons from two ID sources. When the absorber is up (shutter open), the aperture aligns with the 2 White beams and allows them to pass through. Aperture = 6 mm x 14 mm
P4-30 : Bremsstralung Collimation White beam and Bremsstrahlung impinge on the aperture The small White beam spot passes completely through the aperture Bremsstrahlung radiation is collimated (constrained) by the 14 mm x 16 mm aperture This view of the S3-30 collimator is from the downstream end looking upstream
P4-40 : 4-ID-B No mode change Standard S3-30 collimator follows White beam absorber Will stop White Beam, Pink Beam, and Mono- Beam The White beam absorber is smaller than the in the P4-39. The power density decreases because the beam is divergent. The absorber does not need to be as large due to the distance from the ID source (~60 m).
P4-40 : White Beam Absorber The thin surface is made of glid-cop. The larger block is copper. The two are explosively bonded together. Incident angle = 8° Cooling is directed down the center of the actuator. (Top View)
P4-15 Shutter Side View Pink, Mono-shutter Assemblies Bremsstrahlung collimator (12mm x 16 mm White Beam) (50mm x 16 mm Pink, Mono- Beam) White Beam Absorber (Incidence angle = 4.5°) Mono- beam White beam
P4-15 Shutter Mode Keys White beam Absorber lock and pin Pink, Mono- beam Stop locks and pins Safety Stop lock and pin
P4-15 : White Beam Absorber When the White beam absorber is down (Mono- mode), the White beam intercepts the walls (4.5° incident angle) and is stopped.
P4-15 : Pink Beam Absorber When the Pink beam absorber is down (shutter closed), the Pink beam intercepts the walls (16° incident angle) and is stopped. This absorber also acts as a Mono- stop.
P4-15 : Collimator Block White beam aperture (12 mm x 16 mm) Mono- beam aperture Pink beam aperture (50 mm x 16 mm)
P4-15 : White Beam Mode P4 shutter was redesigned by ChemMatCARS to reduce cost and to operate in White beam, Pink beam, and Mono- beam modes. In White beam mode, the Pink/Mono- shutters are locked in the open position and the keys are captured in the PSS panel The absorber is lowered and White beam travels above it The Safety Stop is lowered to allow White beam to pass and Bremsstrahlung radiation is collimated by the 12 mm x 16 mm aperture.
P4-15 : Pink, Mono- Beam Mode In Pink/Mono- beam mode, the White beam absorber is raised and locked in place to intercept the White beam The Safety Stop is lowered to absorb Bremsstrahlung radiation AND its upper aperture allows the less intense beams to pass through.
P4-50 : 24-ID-B, 31-ID-C, 32-ID-A Fixed White beam stop Standard S3-30 collimator follows the White beam stop Mode change occurs by moving the entire device upward
P4-50 : Shutter Side View S3-30 Collimator Fixed White Beam Absorber Aperture = 8 mm x 10 mm
P4-50 : Shutter Mode Keys Mono- stop lock and key(s) Shutter table lock and key
P4-50 : 32-ID-A Absorber Absorber is fixed in place. It has no moving cylinder.
P4-50 : Administrative Restrictions The ability to change modes has been inhibited. Downstream stations are not verified for White Beam. 24-ID-B & 31-ID-C have had their Mono- shutter locks completely removed 32-ID-A has had its Mono- shutter keys placed under Configuration Control