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Dear Shih-Chieh, It seems indeed that the scale at which unitarity is violated is different for Michael and for me. However, there are differences : We do not use the same process, the same operator and maybe also not the same assumptions for the derivation of the unitarity bound. I will look at it for WW scattering with dimension-six to see where the difference mainly come from. Michael, could you give your operator with all the convention and some details how you derive this bound? You can find the details about our result in our paper (1205.4231). Cheers, Celine On Wed, 2012-12-12 at 13:48 -0800, Shih-Chieh Hsu wrote: > Sorry for that I didn't complete my email. Please see a small > modifications below. > > On 12/12/12 1:41 PM, Shih-Chieh Hsu wrote: > > Dear Oscar, Celine and Michael, > > > > Thank you very much for your comprehensive introductions of your > > electroweak effective field theories. > > I learned more depth about different aspects of your EFT today. > > > > I have a couple of questions looking forward to your further comments. > > > > Q1. What is the appropriate approach to probe gauge couplings > > in a consistent way in inclusive diboson, VBS diboson+jj and triboton > > production at hadron colliders? > > > > Celine commented that we don't need energy dependence form factor > > to preserve unitary for WW production by considering all dimension 6 > > operators. > > However, Michael use VBS WW+jj production as an example to show that > > we need to > > introduce s^hat dependent form factor in order to preserve unitarity. > > The TGC limit derived in inclusive WW might not be compared to the TGC > > limit > > derived in VBS WW+jet neither Triboson production. > > > > Q2. Could Oscar give us a summary of the coupling constants with > > necessary form factor for the Dimension 6 and Dimension8 operators? > > To my understanding, we only introduce Dimension 8 operators for > > neutral gauge couplings. > For practical approaches, we agreed to only introduce Dimension 8 > operators for neutral gauge couplings. > > Cheers, > > Shih-Chieh > > > > > Q3. It looks to me VBFNLO, MadGraph5 and Oscar's package all implement > > the same effective field theory. > > Do I understand it correctly that we should be able to reproduce > > the same calculations > > from each generator? > > > > Q4. In the end, the TGC/QGC operators are linear expansions of the > > effective Lagrangian. > > Do I expect the production cross-section can be represented as > > a quadratic dependent function > > of each gauge coupling coefficients? > > > > Sincerely yours, > > > > Shih-Chieh > > > > ######################################################################## > > Use REPLY-ALL to reply to list > > > > To unsubscribe from the SNOWMASS-ELECTROWEAK list, click the following > > link: > > https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=SNOWMASS-ELECTROWEAK&A=1 > > > ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the SNOWMASS-ELECTROWEAK list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=SNOWMASS-ELECTROWEAK&A=1