CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille, France

Introduction to Introduction to s s and mixing WG meetingand mixing WG meeting

Olivier Leroy

s and mixing meeting, March 12th 2009

Introduction to the beta_s and mixing WG meeting, March 12th 2009 2Olivier Leroy

NewsNews

Moriond: no new Bs->JpsiPhi results from Tevatron Depsite ~10fb-1 on tape !

The road map (draft9=LHCB-ROADMAP3-001) was sent to EB on Feb 12

Lively and constructive discussion on CDS (17 comments): http://cdsweb.cern.ch/record/1161566 We are finalizing the answers and preparing the next draft Everyone welcome to participate Before sending new comments, please read:

The road map Comments/answers already available All the supporting notes: they contain much more details than the road map

itself

Introduction to the beta_s and mixing WG meeting, March 12th 2009 3Olivier Leroy

Still to be doneStill to be done

Long pending list of tasks here: https://twiki.cern.ch/twiki/bin/view/LHCb/BetasManpower

In particular: Background

Systematics due to background Toy MC with non-flat angular background Size of side-band needed to not be systematically dominated

Related to stripping (Greig, Marta) Include min. bias additional background (K/pi decays in flight)

Selection optimization criteria Minimizing (stat+syst) uncertainty on betas in practice

No simple mathematical formula to maximize available yet: many compromises Alternative selection with lifetime biased cut allowed

Beta_s sensitivity with low integrated luminosity (Basem) Point estimate not reliable with low integrated luminosity (as CDF observed) Need to construct confidence region to quote first results

Understanding proper time / angular acceptance shapes (Yuehong, Basem) Same side tagging Simplified analysis with first data:

One angle analysis (acceptance of the 2 other angles?) Untagged analysis

S-wave (Yuehong, Concezio, …) Pure CP-even mode studies (Liming) ...

Introduction to the beta_s and mixing WG meeting, March 12th 2009 4Olivier Leroy

Supporting notes for the road mapSupporting notes for the road map

Submitted to EB: G. Lanfranchi et al. “Lifetime Unbiased Selection of Bs->J/Psi Phi and related

control channels: Bd->J/Psi K* and B+->J/Psi K+” T. du Pree et al. “Methods for Angular Analyses of B->J/psiX” 

Draft1 circulating within CP WG: M. Calvi et al. “Flavour tagging calibration of \BsJphi\, \BdJKst\ and \BuJK\

channels” C. Langenbruch et al. “Fit Bs->JpsiPhi” C. Linn et al. “Time and angular analysis of Bd->JpsiK*” C. Gobel, M. Calvi et al. “sin2beta” G. Conti, A. Hicheur, “Trigger preselection of B->JpsiX channels”

Not yet ready: S. Vecchi et al., “Systematics error on proper time and background fractions” A. Hicheur et al., “Jpsi(ee)Phi offline + trigger sel” Y. Xie et al., “KK S-wave” Note on Dms and Same side kaon ? no draft, no schedule ?