2 ready sections (i) 3 ready sections (ii) 4 sections still in preparation it would be also worth...
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Sections still in preparationSections still in preparation
It would be also worth adding a brief section on possible It would be also worth adding a brief section on possible strategies for the startup of the measurementsstrategies for the startup of the measurements
In particular, how to stage the analysis in steps of increasing complexity Will see once all the main sections will be ready
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Physics casePhysics case Introduction to the CP violation formalism to the main Introduction to the CP violation formalism to the main
motivations of the measurementsmotivations of the measurements , U-spin, etc..
Brief review of the experimental status, including all the Brief review of the experimental status, including all the relevant results from the B-factories and CDFrelevant results from the B-factories and CDF
Time dependentasymmetries
Direct CP chargeasymmetries
Branchingfractions
See also Eduardo’stalk later foranother view
Will be later used forWill be later used forevaluating theevaluating theimpact of the LHCbimpact of the LHCbmeasurementsmeasurementsin this sectorin this sector
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Event selectionEvent selection
Offline and online (HLT2) selectionOffline and online (HLT2) selection See Angelo’s review talk later and Laurence’s for the baryonic decays
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PID calibrationPID calibration loglogLL calibration for pions and kaons using the golden calibration for pions and kaons using the golden
D*D*DD decay chain decay chain Crucial work, now being extended to the proton sector with p decays
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Modelization of the invariant mass line Modelization of the invariant mass line shapeshape
Important in order to perform reliable fits of the BImportant in order to perform reliable fits of the Bhh hh mass spectrummass spectrum
Not a trivial task, due to FSR effects Need to properly take into account the
bremstrahlung energydistribution
See specific talkSee specific talklaterlater
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Proper time resolution and acceptanceProper time resolution and acceptance
Parameterization of the Parameterization of the acceptance as a function acceptance as a function of the proper time andof the proper time and3-Gaussian fixed 3-Gaussian fixed resolution modelresolution model
See Laurence’s talk for further studies on the proper time model
Not yet included in the road map document
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Absolute lifetime measurementsAbsolute lifetime measurements
Proof of principle of event-by-event acceptance function Proof of principle of event-by-event acceptance function method and PID-based Bmethod and PID-based BssKK++KK-- HLT selection HLT selection
For a relative lifetime study see Harry’s presentation laterFor a relative lifetime study see Harry’s presentation later
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Misalignment studiesMisalignment studies
Impact of misalignments on the VELO, IT and OT stations Impact of misalignments on the VELO, IT and OT stations on the physics analysison the physics analysis
Parametric study in some misalignment scenarios, ranging from no misalignment to disaster
InterestingInterestingstudy towardsstudy towardsthe understandingthe understandingof systematicsof systematicsassociated toassociated topotentialpotentialtracking issues tracking issues
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Flavour tagging strategyFlavour tagging strategyand performanceand performance
This section hosts a This section hosts a discussion on the peculiar discussion on the peculiar features of the Bfeatures of the Bhh decay hh decay modes concerning flavour modes concerning flavour tagging, outlining a possible tagging, outlining a possible strategy for a proper strategy for a proper employment of the tagging employment of the tagging algorithms and reporting algorithms and reporting measurements of the tagging measurements of the tagging performance on offline performance on offline selected eventsselected events
See specific talk laterSee specific talk later
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CP sensitivity studiesCP sensitivity studies
In this section we write down the complete p.d.f. for time, In this section we write down the complete p.d.f. for time, mass, PID, tagging decision, tagging category, etc..mass, PID, tagging decision, tagging category, etc..
Then we perform maximum likelihood fits of the whole Then we perform maximum likelihood fits of the whole BBhh event sample, comprising Bhh event sample, comprising B3-body and 3-body and combinatorial backgroundcombinatorial background
Both fitting the p.d.f. to toy Monte Carlo samples and to the full Monte Carlo sample which passes the event selection
The fit features about 60 free parameters at present The final fit will exceed 100 free parameters
Although they seem a lot, consider that the CDF analysis features 38 parameters at present, but with mass only fits, i.e. no time dependency
Section towards completionSection towards completion Expected to be ready by the end of the next (LHCb) week
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Simple snapshot of a CP fit on a Simple snapshot of a CP fit on a toy Monte Carlo sampletoy Monte Carlo sample
Projection of the p.d.f. on the invariant massProjection of the p.d.f. on the invariant mass Each color represents a different final state (CP-conjugates are light↔dark)
Light and dark blue: BdK Red: Bd
Yellow: BsKK Light and dark green: BsK
Light and dark orange: bpK Light and dark magenta: bpDark gray: 3-body background Light gray: combinatorial background