Dear Shi-Chieh, Celine and Michael



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.


My guess is that only the VBF channel might violate the unitarity bounds.
In any case, I agree with Michael that we should first check that unitarity is not violated in the 
region where the events are. If this happens (best scenario) we have no problem 
comparing different channels. Probably we will run into trouble for higher energy pp
colliders.

 
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.


I need to collect information that is scattered in many papers. I'll get back to you when I
have it.
 

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?


My understanding is that this is true. The feynrules group  (Celine et al) is releasing a new
package that will allow to interface with aMC@NLO so this will make the comparison easier.
 
greetings, oscar


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