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Dear Chip and Michael,

Sunday 930 PM version.

Slide 5. Lepton colliders statement is generically correct but I think 
misleading.
Only e+e- colliders currently offer competitive sensitivity in all decay 
modes as can be seen from the tables in the Higgs report.

Slide 11,12. Higgs self coupling. Not clear that the muon collider can 
do this given
dominance of nu nu H H as the exploration channel. Also no entry in the 
corresponding table.

Slide 20.
sub-MeV at TLEP -> sub-MeV potential at TLEP
(there has been no demonstration that the systematics on efficiency, 
background and luminosity can
be controlled - this is much harder with no longitudinal polarization. 
The total luminosity is also very debatable ..)

Slide 50. This seems impressive (electroweakinos at LHC), but without a 
full understanding of the caveats / model assumptions /
statement that the low delta_M region is not accessible, it can be 
extremely misleading.
A throw-away naive implication is that LHC has the capability to rule 
out charginos to 800 GeV in mass, whereas my
interpretation of the plot is that there is no model independent 
exclusion of charginos much beyond that
achieved at LEP2 feasible from LHC.

Slide 65.
1. The numbers I have seen that seem to represent a reasonable 
apples-with-apples comparison of ILC and TLEP
    prospects indicate that at 250 GeV TLEP lumi is very similar to ILC 
capability while consuming much more in power.
    ILC can have 3e34 at 250 GeV
    TLEP claims  4.8e34 at 240 GeV per IP.
    So I would not say and be able to defend "possibility of up to 
10*higher luminosity" than ILC at 250 GeV.
    250 GeV looks to more be the cross-over point where linear becomes 
more sensible than circular for a cost-constrained design.

2. I would be careful with comparing the conservative ILC projections 
with the numbers coming from TLEP.
     The systematic errors in sin^2theta and mW are very different.
     It seems unreasonable to put hard numbers on the table for ILC/TLEP 
comparison on those.
     at least change "improve" -> "might improve".
     It is clear that TLEP could have higher lumi below 200 GeV, making 
use of this depends critically on
     being able to control systematics associated with for example 
polarization (for A_LR)which is not so obvious for circular.

     MZ improvement is an improvement over LEP (not over ILC).

        regards
             Graham



On 8/5/2013 12:21 AM, Raymond Brock wrote:
> hi EF conveners,
>
> Now we've had time to actually put things into a talk-like form.
>
> If you go to http://www.pa.msu.edu/~brock/file_sharing/snowmass2013/ 
> <http://www.pa.msu.edu/%7Ebrock/file_sharing/snowmass2013/>
>
> Look at the 930pm titled pdf. What you'll notice is a brutal 
> elimination of words into what we hope is the essence of your 
> conclusions. I might include the full complement of conclusions as an 
> appendix.
>
> o What's not been touched since this afternoon is the physics case 
> slides for the new machines...that requires some thought still to 
> emphasize the important cases. These are meant to be "why" we would 
> build an upgrade or such a facility.
>
> o I'm teetering back and forth about vacuum instability.
>
> o Noticed: Slide 18 should say Knew where to look for the Higgs Boson
>
> So you need to tell me if we've hacked too much, or the wrong things. 
> Again, we're presuming that the audience is not EF colleagues but 
> others who don't do this work every day.
>
> Finally...
>
> o I'm thinking of a slide that says the following. You should tell me 
> how you think this might be received.
>
> A slide that would be horizontal, but would show the following 
> "documentation scale"
>
> LHC   > TDR
>
> ILC    = TDR
>
> ILC-HL = TDR
>
> CLIC  =  CDR
>
> muon collider     < CDR
>
> TLEP     (blank)
>
> This would make two points. First, I continue to feel tension between 
> the natural conservatism built into projecting with a running, 
> battle-scarred real detector at LHC as compared with a highly tuned, 
> but still proposed detector at ILC. I also clearly am sensitive to the 
> tension between the very sophisticated ILC proposals and the really 
> virtual TLEP ideas.
>
> What do you think?
>
> best
> Chip and Michael
>
> ---------------------------------------------------------------
> Raymond Brock  *  University Distinguished Professor
> Department of Physics and Astronomy
> Michigan State University
> Biomedical Physical Sciences
> 567 WIlson Road, Room 3210
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-- 
Graham W. Wilson
Associate Professor
Dept. of Physics and Astronomy
University of Kansas
Lawrence, KS 66045
Office Tel.   785-864-5231
Web: http://heplx3.phsx.ku.edu/~graham/


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