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Dear mu2e Colleagues,

There will be a general mu2e teleconference next Wednesday, Aug. 14 at the
usual time (2 PM eastern, 1 PM Central). One subject I'd like
to begin the discussion of is the issue of what R&D support we should
request for the LOI. We need to begin the process of identifying
what R&D will be necessary and who and what will be required to do it.

Naturally, we hope that our Fermilab colleagues will continue their excellent
work in developing the proton beam. We need to discuss what sort of support they need for this. Is there some area where the
Universities can help particularly addressing issues related to the muon
collection solenoid and target?

We should keep in mind that the MECO design has been pretty thoroughly reviewed
by technically knowledgeable committees and they have not found any
'show-stoppers'. In that sense, we think we have a design with a very high
probability of working. Nevertheless, as always some areas could use
a little more study.

One issue which probably should be addressed is whether the MECO design
could handle potentially as much as 200 kW of beam instead
of the 50 kW of beam planned at BNL. This affects the
primary target heating, PS cryostat heat and radiation load,
the detector system, ...

For the detectors, there remains the issue of which tracker design to use,
and as already mentioned, how high the intensity can go before we
run into problems with backgrounds: false tracks leading to high energy tails
in the energy response function, paralyzed detectors during injection, etc.
We also need to solve the question of whether and how much we
need to cut the tracker and calorimeter HV's during
injection to handle the 'flash'.
Shielding of the Cosmic Ray Veto from the neutrons from the stopping
target probably also needs more study.

One possible goal would be to get more muons in a narrower momentum range.
This will allow stopping more muons in a thinner target (a thinner target
means less energy straggling and improved conversion electron energy
resolution).
Some collaborators (Y. Semertzidis for example) had some ideas to put
baffles into the production and /or transport solenoids to help
reduce late-arriving and other unwanted particles and to narrow the
momentum band. This probably deserves further study.
The work of Muons Inc. should of course be encouraged to see if they can come
up with a cleaner narrower-momentum, muon beam, and perhaps the Universities could work with them in their studies.

We can discuss whether it would be productive to investigate ways to reduce
the cost and/or improve the performance of the solenoid system. We should
realize that a lot of excellent design work has been done, and the
system as proposed is quite a good one, with many clever features.
If we feel we need to save money, then we should probably investigate whether we can relax some of the stringent physics requirements which have been placed on the field gradients.

There will probably be some questions relating to the PRISM/PRIME approach
relative to the MECO approach, and a modest evaluation of the
relative merits of the two approaches might be appropriate.

There are many potential areas of study. I think we need to list what
they might be, then select the few most important.
Please bring your ideas!

Thanks-
Jim