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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.)