Timeline for Higgs mass and EW precision tests
Current License: CC BY-SA 3.0
5 events
| when toggle format | what | by | license | comment | |
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| Sep 17, 2015 at 22:31 | comment | added | Karozo | Good answer, you can't use the unitary gauge for loop processes (you can see that by the propagator of the gauge boson), for example in the $B-\bar{B}$ mixing you have to take into account the Goldston bosons. | |
| May 11, 2015 at 10:41 | comment | added | Clever | I took the definitions from a sheet of paper I found on my desk ;) In the paper you cited on page 18, (4.12)-(4.15) are the definitions. Not (all) the $\Pi$'s are zero, but $\hat{U}$ and $\hat{T}$ are defined as differences. These parameters are not restricted to tree level calculations. However, if you go to higher order, you also have to adjust the 'normalization', i.e. the SM computation. | |
| May 9, 2015 at 8:28 | comment | added | Worldsheep | Aren't S T and U rather parametrising the deviations from the SM at tree level? | |
| May 8, 2015 at 17:17 | comment | added | Worldsheep | Thank you for your explanation. I still don't understand everything of what you have explained (I'm new to the subject). Have you seen how the S T U parameters are defined in the document I have provided? How can they be zero in the SM? Doesn't $\Pi(q^2)$ contain corrections of the form " -O- " where the loop is given for instance by a top and bottom quark? | |
| May 8, 2015 at 17:08 | history | answered | Clever | CC BY-SA 3.0 |