Big Gamma Combination Workbook

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Introduction

Really useful paper with equations is "Effective Lifetimes of Bs Decays and their constrains on Bs mixing parameters": arXiv:1109.5115
Another one which the flavour specific guys (Stone/Gandini) quote to get their equation is EPJ: DOI:10.1007/s100529901079

Input Channels

Bs -> JPsiKK

Contains CP-odd and CP-even mixtures. Best individual constraint on these parameters by far.

src/PDF_BG_JPsiKK.cpp

Theory

• Currently IS NOT CURRENTLY USED
• Direct observation for and

Observables:

Use the paper which is the stand-a-alone BsJpsiPhi 1fb result (i.e. not the update in which it was combined with JPsif0) which is: arXiv:1112.3183.
The 1fb-1 paper which was combined with JpsiPiPi was: arXiv:1304.2600

Bs -> JPsif0

The decay via the f0 resonance alone is completely CP-odd and hence the lifetime can be used as a direct constraint on . There is a more sophisticated analysis which does the full Bs->JPsiPiPi spectrum (i.e. through severeal resonant states) but this again becomes a mix of CP eigenstates (although is 97.5% CP-odd) and hence no breakdown of the lifetimes is provided.

src/PDF_BG_JPsif0.cpp

Theory

• Currently use effective lifetime as direct input to such that
• Could move to correct with: ala HFAG to first order:
  
  See HFAG report Eq. 50 51 and also arXiv:1109.5115

Observables

• 
• which gives
• This is the the JPsif0(980) 1fb result arXiv:1207.0878v3
• This information must be available for 3fb given that there has been a full JPsiPiPi analysis (severeal resonanances) with CP-odd and CP-even components although I can't find a particular result. The all resonanaces paper is arXiv:1405.4140 which is LHCb-ANA-2014-021

Bs -> DsDs

This is now a pure CP-even eigenstate so we get direct access to via the effective lifetime measurement.

src/PDF_BG_DsDs.cpp

Theory

• Currently use effective lifetime as direct input to such that
• Could move to correct with: ala HFAG to first order:
  
  See HFAG report Eq. 50 51 and also arXiv:1109.5115

Observables

• 
• which gives
• comes from this paper 3fb: arXiv:1312.1217
• this paper also includes the Bs -> D-Ds+ flavor-specific lifetime which maybe can be used as well? (similat to DsPi?)

Bs->KK

Also a pure CP-odd state so similarly to DsDs the effective lifetime gives acces to . Similarly might be useful to reparameterise in terms of

src/PDF_BG_KK.cpp

Theory

• Currently use effective lifetime as direct input to such that
• Could move to correct with: ala HFAG to first order:
  
  See HFAG report Eq. 50 51 and also arXiv:1109.5115

Observables

• 
• which gives
• comes from this paper 1fb: arXiv:1406.7204
• this paper also includes the Bs -> pi+K- flavor-specific lifetime which maybe can be used as well? (similar to DsPi?)

Bs -> DsPi

This is a flavour specific channel (has access to both and

src/PDF_BG_DsPi.cpp

Theory

• Actually gets rather tricky here
• Make the assumption that under NO (neglible) CP violation in Bs mixing that the following is true
  
  
• This is used by the DsPi guys and they cite EPJ article here

Observables

• 
• can be used with above to constrain and
• comes from 1fb: arXiv:1407.5873
• uses the know B0 lifetime as input

Useful Links