Undergrad Decay of the Bs0 particle and supersymmetry

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The first single-experiment observation of the decay Bs0→ μ+μ- was reported, with a branching fraction of (2.8±0.6)x10-9, aligning with Standard Model (SM) predictions. This decay is significant for exploring potential new effects of supersymmetry, which has been a focus for over 30 years. Recent results show that the decay B^0→ μ μ is now closer to SM predictions, narrowing down the parameter range for supersymmetry models without ruling them out. Discussions also highlighted the flexibility of supersymmetry theories and the anticipation of results from the 2016 LHC run, expected in March. Overall, the findings contribute to the ongoing search for evidence of beyond the Standard Model physics.
kodama
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14 February 2017: First single experiment observation of the decay Bs0→ μ+μ-.
From discovery to precision measurement.
[ Branching fraction Bs0→ μ+μ- = (2.8±0.6)x10-9 ; B0→ μ+μ- < 3.4x10-10 ]

"“We love this decay because it is one of the most promising places to search for any new effects of supersymmetry,” Archilli says. “Scientists searched for this decay for more than 30 years and now we finally have the first single-experiment observation.”

the decay and lifetime is accord with SM predictions

how does supersymmetry effect decay in precision measurements and how many standard deviations does supersymmetry effects differ from SM, and from LHCb results?
 
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Nice to see that result.

##B^0 \to \mu \mu## was a bit above the SM expectation in previous results, now it is closer to the SM prediction again.

The predictions with supersymmetry cover the whole interesting range, sometimes even values below the SM prediction. You cannot rule out supersymmetry that way, but it narrows down the parameter range a lot.
 
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mfb said:
Nice to see that result.

##B^0 \to \mu \mu## was a bit above the SM expectation in previous results, now it is closer to the SM prediction again.

The predictions with supersymmetry cover the whole interesting range, sometimes even values below the SM prediction. You cannot rule out supersymmetry that way, but it narrows down the parameter range a lot.

any specific details, esp in combination with other constraints from other measurements supersymmetry? is MSSM or nMSSM still viable, or does something like nnMSSM is needed?
 
You can find specific details in the specific publications of your favorite SUSY model.
 
mfb said:
You can find specific details in the specific publications of your favorite SUSY model.
what is your favorite SUSY model? one that survives all previous constraints ?

any SUSY rumors on 2016 LHC run?
 
My favorite SUSY model is no SUSY.

Every experimental evidence for BSM physics would be better than no such evidence, no matter which theory it supports, but until we have such evidence I don't care much about SUSY. It is just too flexible with its 1xx free parameters.
 
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mfb said:
My favorite SUSY model is no SUSY.

Every experimental evidence for BSM physics would be better than no such evidence, no matter which theory it supports, but until we have such evidence I don't care much about SUSY. It is just too flexible with its 1xx free parameters.
has there been any rumors of any bsm about the 2016 lhc run, some 40 fb-1? when will results be announced?
 
First results are expected by Moriond in March. I can't (and don't want to) comment on rumors.
 
mfb said:
First results are expected by Moriond in March. I can't (and don't want to) comment on rumors.

March is only a few weeks away. will results reflect analysis of the full 2016 40 fb-1 plus 2011-2015 data, or only a small fraction of 2016 results?
 
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We had a small fraction of 2016 data for ICHEP in August already.

Most searches will probably use the full 2016 dataset (+2015). It doesn't make much sense to publish results now that are based on a part of the 2016 dataset. If the analyses are not done yet, the results will be shown later. More complex analyses need more time.
 
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