Slow controls and instrumentation of MICE 1.Physics and systematics 2.How the state of the cooling channel gets defined 3.Engineering for the signal readout 4.Data Record M. A. Cummings Feb

Alain’s physics lecture Mice fiction in 2007 or so….. MICE measures e.g. (  out  in ) exp = ± (statistical) and compares with (  out  in ) theory. = and compares with (  out  in ) theory. = um, okay.. Could we understand this???. SIMULATION REALITY MEASUREMENT theory systematics: modeling of cooling cell is not as reality experimental systematics: modeling of spectrometers is not as reality Correct geometries TRIUMF data Beam diagnostics Proper emittance population Tracking and particle ID Cooling channel systematics

  Stated Goal  out /  in of  10 –3  Assume there will be a standard (or agreed to) definition of 6-D cooling.  What are the beam diagnostics concerns in a single particle experiment? How is beam diffusion controlled? Backgrounds?  We can also assume that the tracker can give us precision particle position and momemtum that this won’t contribute significantly to the error.  Particle ID < 1% error  The sources of systematic errors in the COOLING CHANNEL need to be under control to a level that 10 independent sources will be < the same level  A. Blondel: goal to keep each source of error <3*10 -4 level if at all possible. Systematics assumptions and questions

Instrumentation and controls  Beam diagnostics: Dipoles, “twiss” params, halo, etc.  Monitoring/safety: LH2 controls, RF, Magnets, cryogenics “slow” ~ 1 Hz  Data acquisition: information on each event Information on system state:  dE/dx density  Magnetic field  RF field  Calibration: Magnetic fields:  Offline field maps  Fringe fields  Survey/alignment  Tracking with online monitoring  Subsystems Absorbers RF Magnets

Cooling channel readout: design  Cooling channel component state (physics) Temperature inside the the absorber/vacuum Pressure on the LH2 outlet Magnetic field measurements: currents (probes) power supply location monitors RF: power, tuning, phase  Controls ( state of the system included in data record) LH2, Magnet and RF Safety systems (subset of monitoring describing the “state” of the system) Temp/flow on Helium Optical occlusion methods (laser or non-laser)  Design considerations (depends on the final dimensions, routs, ports) LH2/flammable gas safety Clearance and strain relief Feedthroughs to outside electronics Noise cancellation/shielding Robustness

Signal transfer (cooling channel)  Wire and Shielding Concerns ¤Cable plant into solenoid Shielded-twisted pairs (two pairs per Cernox) –Shield drains carried from Lakeshore(s) to sensors (not grounded) Grounding –Details depend on overall MICE grounding scheme ¤Common mode (surges) due to magnets Need to protect electronics without burning barriers ¤Noise/sensitivity issues  Feedthroughs ¤Vacuum compatible, electrically insulated ¤Have to decide pin configuration based on 2, 4 wire readouts ¤Commercially available..MDC vacuum products

Experimental controls channel list what info source how many channels who determines Beam diagnostics?Tilley/Palmer Tracker/ particle IDBross/Bonesini Magnetic Fields50Rey/Guyot Alignment50Black/Linde Slow controls?Baynham RF?D. Li Magnets10 *3Green Absorbers20 *3Cummings Is this the right approach now?

The magnetic measurement devices as from the proposal see pages 52, 53. NB, we need to know *where* the probes are for this to work : The magnet system will be operated in a variety of currents and even polarities and it is difficult to assume that the field maps will simply be the linear superposition of those measured on each single magnet independently: forces are likely to squeeze the supports and move the coils in the cryostats. we will measure the magnetic field with probes (NIKHEF) (contacts Frank Linde and Frank Filthaut and ) A. Blondel, TB talk

Global monitoring and experiments  Want to record a full configuration of the experiment at every “pulse”.  Pulse = trigger = ?  Will be running with different configuration of calibration run in order to get a handle on the systematics: ¤With RF, no beam ¤without RF, beam ¤without any ¤with both RF and beam. ¤With magnets no absorbers ¤With magnets one absorber ¤Magnets, with and without RF  Want to start understanding the tolerances needed for emittance measurement

Example of such: Coil tilt tolerance. Take U. Bravar's MICE note 62: this looks like a quadratic dependence. it takes 4 0 =0.068 rad to get a change by ==> it will take  (tilt) = 0.068rad x sqrt(0.001/0.065) to get a change by this is 8mrad or 0.5 degrees. this sensitivity is (3x) smaller than the tolerance calculated by U. Bravar, because MICE will be sensitive to effects that are somewhat smaller than what is assumed to be needed for the cooling channel. similarly for the transverse position I find ~6mm tolerance instead of 20mm From A. Blondel TB talk:

quantitydesign tol.monitoringwith beam / exp. conf beam optics transfer matrix: for ex. (p t, p L, phi, x 0, y 0 ) in (p t, p L, phi, x 0, y 0 ) out measure with no RF and empty absorbers each time one changes the mag set-up. positions of coils internal survey some mmalignment position monitor currentssome amp-meter position monitoring mag fieldsome mag probes amount of absorber (in g/cm 2) 3*10 -3 = 1mm/35 cm density through T & P thickness.. Optical occlusion? measure energy loss of muons for 0 absorber, 1 absorber, two absorbers with RF off. RF field measure E to dE/E= Measure phase measure energy of muons vs RF phase before and after cooling channel  What physics controls can we define?  How can we control it by design tolerances / by monitoring / with the beam itself

 example of such an experiment E out -E in (GeV) simulated by Janot in 2001(nb: this was at 88 MHz) … this measures E RF (t) E RF (  ) dependence…

So far… the required monitoring should consist of: -- Ampermeter for each coil -- Magnetic field measurement -- monitor position of probes and coil assemblies (with ref. to an absolute coordinate system) -- E RF (t) (gradient and phase of each cavity) -- absorber density (i.e. T & P) and thickness. -- Beams -- Cryo  Look toward how we do this in a neutrino factory  Want to get information unique to this cooling experiment e.g. the muons themselves will provide very powerful cross- check (energy loss and energy gain, transfer matrix)