Attendees: Rebecca, Shanjie, Armin, Eliazar, Eric, Alex, Eliazar, Marc, Ophelia
*Alyssa on vacation for next 2 weeks
Agenda:
- MFX photon dump sizing
- CXI KB mirror shielding
- Note Status: DRAFT circulated
- Stopper location in XRT Alcove
- XRT collimators
- Raytrace methodology
Discussion:
- MFX photon dump sizing
- Assumptions: KB locations IP ; sample is worst case reflector; mirrors are silicon. Calculations will be run for various beam powers. Various concrete burnthrough limits.
- We have a preliminary size based on single pulse damage only but we need to know load from steady state
- sheetrock burnthrough...or should we put layer of something else?
- Concrete wall burnthrough calc for XPP. held up...we need help with assumptions/calc check
- more info needed on KBs: substrate coating, focal length range
- focal length ~4m?
- substrates?
- CXI KB mirror shielding
- Note Status: Shanjie circulated draft 10/29
- Info needed:
- check mech. drawings
- (maybe design changes coming...TBD after meetings with SACLA)
- Stopper location in XRT Alcove
- Requirements to consider?
- check prefocusing lenses - we are removing. confirm. - yes we will remove
- stopped
- XRT collimators
- need upgraded L2Si version (2 locations)
- Yiping is looking into the air attenuation calc.
- air attenuation calculations need to be vetted - by whom??? Ask Yiping who he knows in the community.
- David asked Yiping to start working on it
- latest study on tunneling through air...papers: https://journals.iucr.org/s/issues/2016/01/00/xt5002/index.html
- someone from DESY can help?
- is our gas attenuator going to work?
- HXR atten needs upgrades to get to 2x pressure
- We should be concerned here?
- https://slac.sharepoint.com/sites/pub/Publications/BCS_Absorber_Diode_Based_BTM.pdf?CT=1614317177038&OR=ItemsView
- https://portal.slac.stanford.edu/sites/lcls_public/lcls_ii/acc_phy/technotes_lib/LCLS-II-TN-15-25.pdf
- https://portal.slac.stanford.edu/sites/lcls_public/lcls_ii/acc_phy/technotes_lib/LCLS-II-TN-15-24.pdf
- https://portal.slac.stanford.edu/sites/lcls_public/lcls_ii/acc_phy/technotes_lib/LCLS-II-TN-15-23.pdf
- air attenuation calculations need to be vetted - by whom??? Ask Yiping who he knows in the community.
- Collimator type and material
- reuse XTES design? or TBD
- Solid atten has thick Si
- operable to 25kEv (w/Si+SSt) - hack in XRT
- Diamond, Silicon, and Germanium planned for new Solid attenuator
- Power Slits - change blade
- BeO2 ceramic blades? TBD
- 10x more absorbant than Si??
- Scatter Slits
- No change - just limit insertion range
- Raytrace methodology
- build tolerances into raytrace?
- Shanjie will send an example
- drawing method
- spreadsheet data?
- reference files
- RP requirements says you need to consider tolerance but doesnt prescribe how we do that
- build tolerances into raytrace?