Also Thanks Flip for some good theoretical perspective. And healthy skepticism is always appreciated

Cheers,
Regina

CP observables, such as D0′s semileptonic asymmetry result, provide a chance to indirectly observe new physics. Unfortunately, while these observables are great channels for looking for deviations from the Standard Model, they are not very good at discriminating between possible new models. In other words, they’re great for identifying that there should be new physics, but it’s much more difficult to extract details about the nature of the new physics.

Also, I should remark that this result should be taken with a grain of salt. In addition from the CDF null results mentioned above, the D0 results seem a bit fishy since the deviation from the Standard Model is *too* large when taken at face value. These kinds of observables are well-constrained by self-consistency conditions, and the D0 mean value for this observable takes a bit of work to make it consistent. For more details for experts, see, e.g. the first section of [1005.4238]. So while the signal may indeed be 3 sigma, one should also have some healthy skepticism that there might be a systematic effect. (I’m *not* an expert on the experimental side, so don’t this as anything other than naive, uninformed speculation.)

Cheers,
Flip

@TimG – You’re totally right. Thanks for the catch! I was trying to say they had either a b or anti-b (its antiparticle partner) but it didn’t come out right

@Mark – will do… maybe that will be my next post

Please do so