Linear Optics Verification for PEP-II using Model-Independent Analysis
نویسندگان
چکیده
We verify all quadrupole strengths (both normal and skew) and determine sextupole feed-downs as well as all BPM gains and BPM cross-plane couplings by an SVDenhanced least-squares fitting of the phase advances (only those which are accurately determined) and the Green’s functions (specified by the local transfer matrix components R12, R34, R32, and R14). The phase advances and the Green’s functions are obtained by analyzing turnby-turn Beam Position Monitor (BPM) data from highresolution model-independent analysis (MIA). Once the magnet strengths are verified, a magnet correction priority sequence can be exercised in the computer before one tries to correct the real accelerator. Results from PEP-II LER measurement are presented.
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