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Also, by the time we have a VLHC, the theory prediction will certainly by known to greater than 30%. We have the technology now to do this. On Fri, Aug 23, 2013 at 12:58 PM, Christopher G. Tully < [log in to unmask]> wrote: > Hi Graham, > The 8% precision on the Higgs self-coupling from VLHC comes from white > paper submitted > by Wei-Ming Yao and this analysis reproduces the results for HL-LHC and > extends the analysis > to HE-LHC and VLHC. Jianming is away, but knows the status of the > documentation for that > analysis (which I gather you have not seen). > It is true that there is another potential source for higher precision on > the Higgs self-coupling. > The 6 TeV muon collider has the potential to achieve 2% and if this white > paper contribution > arrives in time with the full background simulation, then we will revise > that conclusion point. > Best, > Chris > > > On Aug 23, 2013, at 12:11 PM, Graham W. Wilson <[log in to unmask]> wrote: > > > Hi Rick, > > > > I haven't followed the hadron collider Higgs self-coupling > discussion in detail, but from a quick reading of the > > draft Higgs report and relevant papers (I couldn't find ref 69), it > seems clear that double-Higgs production statistics > > is likely to be a strength of VLHC. But how much this translates into a > Higgs self coupling measurement > > and in particular a model-independent measurement of the Higgs > self-coupling when there is a 30% error on > > the theoretical cross-section and many different non HHH coupling > contributions to final states with HH is not clear at all. > > So I don't think your "likely the best place for Higgs self-coupling" is > supported by the current documentation. > > > > regards > > Graham > > > > On 8/23/2013 9:45 AM, Rick Van Kooten wrote: > >> On 8/22/13 8:57 PM, Peskin, Michael E. wrote: > >>> > >>> Dear Colleagues, > >>> > >>> I attach the most recent versions of the Snowmass Executive Summary > and the > >>> EF 5-page summary. We will discuss these in our meeting tomorrow. > >>> > >>> The Executive summary got somewhat rearranged. The frontier conveners > >>> wanted the capabilities sections pulled out and merged into a common > section. > >>> This means that the accelerator part of the LHC, ILC, and VLHC > discussion > >>> occurs much later in the document. But, please look it over. I did > insert > >>> language on the US leadership in high-field magnets. > >> > >> Regarding the current top-level executive summary, I would like to see > the _unique_ capabilities of e+e- machines stressed, and as one example: > >> > >> "They can reach sub-percent precision in the Higgs boson properties, > allowing discoveries of percent-level deviations predicted in theoretical > models." > >> > >> to > >> > >> "They can reach sub-percent precision in the Higgs boson properties in > a unique, model-independent way, allowing discoveries of percent-level > deviations predicted in theoretical models." > >> > >> This is just transferring some wording from the longer summary. I > believe that we are all agreed that an "all hadron" option, i.e., HL-LHC -> > HE-LHC/VLHC would definitely be missing out on important physics and > capabilities and we want to make that clear. > >> > >> Also a small suggestion: adding "at least", i.e.,: > >> > >> "They can improve the precision of our knowledge of the $W$, $Z$, and > top properties by at least an order of magnitude". > >> > >>> > >>> As to the rest of the VLHC discussion, let's talk about it tomorrow. > The > >>> new particles group would like a stronger endorsement of VLHC in the > executive > >>> summary. I am rather cool to this, because the VLHC is not on the > table > >>> now. It would be good to get more opinions from the members of > >>> our group. > >> > >> There is no denying that a ~100 TeV VLHC brings a lot to the table > (including likely the best place for Higgs self-coupling) and we should say > this, but with the caveats that Graham clearly points out. I do like > Ashutosh's suggested wording encouraging a conceptual design report which > is what would be needed to come to more solid conclusion. We could preface > his encouraging statement with "Although beyond the 20-year timeline of > this report, further investigations of the physics and technical issues > would be opportune at this time..." (and indeed the same holds true for > TLEP). > >> > >> Regards, > >> Rick > >> > >> > > > > > > -- > > 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/ > > > > ######################################################################## > > Use REPLY-ALL to reply to list > > > > To unsubscribe from the SNOWMASS-EF list, click the following link: > > https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=SNOWMASS-EF&A=1 > > ######################################################################## > Use REPLY-ALL to reply to list > > To unsubscribe from the SNOWMASS-EF list, click the following link: > https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=SNOWMASS-EF&A=1 > ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the SNOWMASS-EF list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=SNOWMASS-EF&A=1