Minutes of 2nd Harmonic Cavity Meeting on 04 Apr 2014
====================================

Attending: C.Y. Tan, B. Pellico, G. Romanov, Y. Shylnov,
L. Spentzouris, R. Madrak, D. Wildman and B. Zwaska

(1) Tan gave an overview of what had been happening. Mainly
    simulations done bY Gennady and measurements done by Robyn and
    Dave.
    
(2) Some questions and things people volunteered to do in the
following weeks:
	  (a) Check AlN properties. Especially on its longevity.
	  (b) Robyn and Dave will procure some AlN and AL800 samples
	  to be tested.
	  (c) Bill will ask Vladimir Kashikhin to simulate a "real"
	  solenoid that will be able to give us the fields that we
	  need.
	  (d) Research topics:
	      (i) Can water be used instead of AlN disks?
	      	  Talk to SNS
		  Talk to Weiran Chou about KEK finemet cavity which
		  uses water
	      -- Tan
	      (ii) Is there any other material other than AlN that is
	      just as good? -- Linda
	   (e) Robyn will work on getting tan(delta) from the s11
	   data.
	   (f) Tan will contact Ferroxcube and National to find out
	   whether they can make AL800 and the size that they can make
	   them in.


All at the meeting agree that the solenoid design will constrain how
the cavity can be designed and this needs to be worked on.

Other points:
      (i) Shape of ceramic disk that isolates vacuum from air is
      important for RF considerations:
      		(a) disk vs cone. Cone is better than disk
	(ii) Shunt impedance of cavity is probably 100's of kiloohms.
	(iii) Modified Booster PA will work for this cavity -- needs
      to cover 77 - 107 MHz.
      	 (iv) Simulations need to done to understand how solenoidal
      field will affect beam.
      	 (v) Final dimensions cannot be set until solenoid is set.
	 (vi) Coupler will be capacitively coupled into the cavity.
	 (vii) Eddy currents need to be considered in the design
      especially on the walls that hold the coils and the surfaces of
      the cavity.
      	  (viii) Make sure when we design the water cooling channels,
      that eddies and turbulent flow is considered.