Aperture Model
Envisage on-line aperture model providing:
- Full description of both rings - all elements including beam screens, vacuum chamber elements, transitions, detectors, TAN, TAS.
- Design aperture plus any alignment errors to be included. Plus tolerances. Track any changes to the model.
- (Access to known non-conformities.)
- Functions to derive aperture at given element or location, or element range or location range
- "Continuous model of the aperture for each of the two sequences LHCB1 and LHCB2 as a Mathematica function" (JJ)
- Incorporation of beam-based aperture measurements.
- Access to measured closed orbit, separation and crossing angle bumps...
- Inclusion of moveable elements such as collimators and roman pots.
- Include transfer lines, injection region
Applications
- Aperture scans - on-line plot of closed orbit, beam envelope, aperture and possibly beam loss monitors
- Similarly for background optimization: on-line plot of LSS aperture including closed orbit, BLMs, BCMs, tertiary collimators, separation and crossing angle bumps.
- Collimator scans: aperture, collimator positions, down stream losses
- Similarly for injection region scans.
Proposal
- Pull in extended element list from layout database including vacuum chambers, beam screens etc.
- Import aperture model from MAD in LSA database - put onus on aperture model exported to MAD from the layout database to be uptodate and complete. Version control - archive on update.
- Provide client API in JAVA to given aperture as function of element/location/ range etc.
- Provide client API to return closed orbit at any given time. Plus any known applied bumps.
- Provide client API to return collimator positions at any given time
- (Possible interface to Mathematica to give continous function if deemed necessary.)