Block FWCOEF

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I think in the final write-up of the proposal it will be very good to give in the Appendix a translation of the basis of Wilson coefficients used in the FLSHA to the other commonly used basis. This will maybe encourage the other authors of the flavour programs to more easily adopt the FSLHA, even if they use another basis. Muehlleitner, 13:23, June 25, 2009.

Hi Margarete please read my comment on the four-tildes signature. Cheers Pietro 13:25, 25 June 2009 (UTC)

Full WC's or NP part only?

Hi, I am wondering if we should allow for separate blocks for the "New Physics" and "SM" parts of the Wilson Coefficients. Cheers Pietro 17:22, 27 June 2009 (UTC)

Hi Pietro, This is the approach that Aoife and I use in our code and it has worked well. It gives us more discretion to treat the NP contribution to the Wilson coefficients differently than the SM in for example the evolution code. It also means that all tools can use the same version of the SM as a reference point. If we don't do this, we should at least define how one should be extracted from the other (C_i = C_i^SM + C_i^NP at MW for example). Cheers, Will. Wreece 11:34, 29 June 2009 (UTC)
Indeed, I was asking this because my program for b->s gamma, SusyBSG, also treats the NP contribution differently from the SM contribution. Cheers, Pietro 14:55, 29 June 2009 (UTC)
Hi Pietro, do you treat non-SM operators also? I guess it would be fine for the SM contribution to for e.g. C7' to be 0 (or close enough), and the entire operator to be in the NP part. In this case, perhaps the rule should be that Wilson coefficients not explicitly defined should be zero. Will. Wreece 15:21, 29 June 2009 (UTC)
What we must do is define the format of the blocks. Then which entries are actually filled depends on the individual codes (it would anyway be reasonable to decide that the missing entries are zero). One option might be to duplicate the blocks, I mean replacing FWCOEFF with, e.g., FWCOEFFSM and FWCOEFFNP. Or, in alternative, we could introduce another entry in each line of the block, which would be e.g. 0 for SM+NP, 1 for SM-only and 2 for NP-only. This would limit the proliferation of blocks (we already have proposals for creating different blocks for each kind of flavour transition, e.g. Delta_B =1, Delta_B = 2, and so on). Cheers, Pietro 10:42, 30 June 2009 (UTC)
Hi Pietro. I like your second idea more. Perhaps it can be extended further to incorporate the Delta_B number also. I was looking at the SLHA docs, but I can't see whether there can be multiple arguments to the block, like FWCOEF Q=4.6 D=2 where D is Delta_B. I see your point that we don't want to fill a format will blocks which are almost exactly the same. Wreece 15:39, 1 July 2009 (UTC)
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