Field modeling

J. Nelson

2/2/05

Tracking support meeting

Since we last met

• Put out action itemshttp://www-hep.physics.wm.edu/~jkn/minos/tracking/0501_tracking.txt

• Please send comments and corrections

More progress

• Francisco will be liaison with Bob Wands on modeling– Bob well on the way to a variable slots model

• Gets rid of one functional B-B’ mapping for variable gaps

– Strategizing on the end effects model• Geometry limited by number of elements• Talking with Bob about

– Partial slots and gap– Gap & no slots– Fall back position is no gaps & no slots

» Would need to treat the end model as a correction to original

– Need to spec the conductor path in ISM gap• JKN & Francisco• Useful for mass distribution in the new geometry too• (see next page)

Coil Exit Geometry

Bfield interfaces• Talked to Robert…

• Put in Jeff’s variable gap B -> B’ with parameters• Put in Jeff’s B-H variation model (also B->B’) with parameters for all plates • Plane by plane overall scale factors

– Will eventually be results of • Bdot correction * Bdot calibration * global correction• 1st is the hysteresis data from the bdot system• 2nd is the channel-to-channel calibration of the bdot ADCs• 3rd muon calibration for the SM1/SM2/ND from range vs curvature

• Put in Erik’s collar and coil models with parameters• Provision for Robert’s field admixture model for effects• Need to have plate-by-plate B->B’ mappings for B-H curve corrections

– Eventually interface to DB table for B-H and construction information about what heat is were in a plane

• Provision for modeling the air field in the SM gap in 6cm planes of air – Is this easy ???

Bdot system• Coordination meeting on Tuesday

– Francisco has verified the can use same code for ND & FD coil control (life gets easier)– Bench test up an running at W&M – Keith (W&M UG), Francisco, and Jason Koskinen working on merging various code

• Jason’s revisions to output table and timing• Jason’s input table methods• Keith’s drift calibration and current limiting code• Francisco on debugging some hardware at Soudan (time outs)• Francisco bench verification of signal

– Goal is to converge by end next week– Some longer term items (ADC calibration, client server)

• Running now requires a few days without beam to attempt to run– Test and them optimize run (currently 4 hours per loop)

• A few days or ~4 runs– Collect production data (few hours per SM)

• FD polarity put back to normal yesterday

• ND magnet ran for many hours without problem– Only waiting on ND switch control with Bdot for bdot running– System fine for normal operations