fitDeltaT Class Reference

Inheritance diagram for fitDeltaT:

Collaboration diagram for fitDeltaT:

Public Member Functions
def	__init__ (self)
def	event (self)
def	terminate (self)

Public Attributes
	nentries
	Total number of analyzed events.
	DT
	Time difference between the decays of the two generated B mesons.
	Tsig
	Decay time of the signal B mesons. More...
	Ttag
	Decay time of the tag-side B meson.
	DT0
	Production time of the B mesons.
	Tau
	B0-meson lifetime.
	A
	Direct CP-violation parameter (CP violation in decay).
	S
	Mixing-induced CP-violation parameter (CP violation caused by the overlap between mixing and decay phases)
	DM
	Mass difference between the two B0-mass eigenstates.
	Norm
	Normalization factor of the quantum mechanical pdfs.
	BetaGamma
	Lorentz boost of the B mesons.
	q
	Flavor of the tag-side B0 meson at the time of its decay.
	qsig
	Flavor of the signal-side B0 meson at the time of its decay.
	fitData
	RooDataSet containing DT and q for each event.
	fitDataTag
	RooDataSet containing Ttag and q for each event.
	fitDataTagDeltaTPos
	RooDataSet containing Ttag and q for positive DT.
	fitDataTagDeltaTNeg
	RooDataSet containing Ttag and q for negative DT.
	fitDataSig
	RooDataSet containing Tsig and q for each event.
	fitDataSigDeltaTPos
	RooDataSet containing Tsig and q for positive DT.
	fitDataSigDeltaTNeg
	RooDataSet containing Tsig and q for negative DT.
	B0sInTagSide
	Number of tag-side B0s (positive flavor).
	B0barsInTagSide
	Number of tag-side anti-B0s (negative flavor).
	B0sInSignalSide
	Number of B0s in the signal side (positive flavor).
	B0barsInSignalSide
	Number of anti-B0s in the signal side (negative flavor).
	fractionB0barInSignalSide
	Fraction of anti-B0s in the signal side.
	fractionB0InSignalSide
	Fraction of B0s in the signal side.
	DeltaZsigUpsilon
	Difference between the production and the decay vertices of the signal-side B0 meson in z direction.
	DeltaZtagUpsilon
	Difference between the production and the decay vertices of the tag-side B0 meson in z direction.
	fitDataDeltaZsigUpsilon
	RooDataSet containing DeltaZsigUpsilon and q.
	fitDataDeltaZtagUpsilon
	RooDataSet containing DeltaZtagUpsilon and q.
	TsigPosNeg
	Empty variable just to define the limits of the frames in the plots for Tsig.
	TtagPosNeg
	Empty variable just to define the limits of the frames in the plots for Ttag.

Detailed Description

This class makes plots to validate the generated CP asymmetry. It saves the decay time information of the simulation
for both B mesons by running as a basf2 module.  It fills the information in RooDataSets and at the end it fits the
known quantum mechanical pdfs to the delta T distribution and the individual decay time distributions of
the signal and the tag-side B mesons to check if the S and the A parameters in the simulation are correct.

Definition at line 252 of file B0_GenDeltaTFit.py.

Constructor & Destructor Documentation

__init__()

def __init__

(

self

)

Here the module initializes by declaring the variables corresponding to the interesting physical parameters and
decay times. The RooDataSets where the information will be saved are also declared.

Definition at line 324 of file B0_GenDeltaTFit.py.

    def __init__(self):
        """
        Here the module initializes by declaring the variables corresponding to the interesting physical parameters and
        decay times. The RooDataSets where the information will be saved are also declared.
        """
        super().__init__()
        self.nentries = 0
 
        self.DT = ROOT.RooRealVar("DT", "#Delta#it{t}", 0., -11., 11., "ps")
        self.Tsig = ROOT.RooRealVar("Tsig", "#it{t}_{sig}^{gen}", 0., 0., 11., "ps")
        self.Ttag = ROOT.RooRealVar("Ttag", "#it{t}_{tag}^{gen}", 0., 0., 11., "ps")
        self.DT0 = ROOT.RooRealVar("DT0", "DT0", 0., -7., 7.)
        self.Tau = ROOT.RooRealVar("Tau", "Tau", 1.525, 0., 4.)
        self.A = ROOT.RooRealVar("A", "A", 0, -1, 1)
        self.S = ROOT.RooRealVar("S", "S", 0, -1, 1)
        self.DM = ROOT.RooRealVar("DM", "DM", 0.507)
        self.Norm = ROOT.RooRealVar("Norm", "Norm", 2, 1, 8)
        self.BetaGamma = ROOT.RooRealVar("BetaGamma", "BetaGamma", 0.5, 0.1, 1)
 
        self.q = ROOT.RooCategory("q", "q")
        self.q.defineType("1")
        self.q.defineType("-1")
 
        self.qsig = ROOT.RooCategory("qsig", "qsig")
        self.qsig.defineType("1")
        self.qsig.defineType("-1")
 
        self.fitData = ROOT.RooDataSet("fitData", "fitData", ROOT.RooArgSet(self.DT, self.q))
        self.fitDataTag = ROOT.RooDataSet("fitDataTag", "fitDataTag", ROOT.RooArgSet(self.Ttag, self.q))
        self.fitDataTagDeltaTPos = ROOT.RooDataSet("fitDataTagDeltaTPos", "fitDataTagDeltaTPos", ROOT.RooArgSet(self.Ttag, self.q))
        self.fitDataTagDeltaTNeg = ROOT.RooDataSet("fitDataTagDeltaTNeg", "fitDataTagDeltaTNeg", ROOT.RooArgSet(self.Ttag, self.q))
        self.fitDataSig = ROOT.RooDataSet("fitDataSig", "fitDataSig", ROOT.RooArgSet(self.Tsig, self.q, self.qsig))
        self.fitDataSigDeltaTPos = ROOT.RooDataSet("fitDataSigDeltaTPos", "fitDataSigDeltaTPos", ROOT.RooArgSet(self.Tsig, self.q))
        self.fitDataSigDeltaTNeg = ROOT.RooDataSet("fitDataSigDeltaTNeg", "fitDataSigDeltaTNeg", ROOT.RooArgSet(self.Tsig, self.q))
 
        self.B0sInTagSide = 0
        self.B0barsInTagSide = 0
 
        self.B0sInSignalSide = 0
        self.B0barsInSignalSide = 0
        self.fractionB0barInSignalSide = 0.7057091319609885
        self.fractionB0InSignalSide = 0.2942908680390115
 
        # Study od Delta z
 
        self.DeltaZsigUpsilon = ROOT.RooRealVar("DeltaZsigUpsilon", "(#it{z}_{sig}^{dec} - #it{z}_{sig}^{prod})^{gen}", 0., 0., 0.8)
        self.DeltaZtagUpsilon = ROOT.RooRealVar(
            "DeltaZtagUpsilon",
            "(#it{z}_{tag}^{dec} - #it{z}_{tag}^{prod})^{gen}",
            0.,
            0.,
            0.8,
            "mm")
        self.fitDataDeltaZsigUpsilon = ROOT.RooDataSet(
            "fitDataDeltaZsigUpsilon",
            "fitDataDeltaZsigUpsilon",
            ROOT.RooArgSet(
                self.DeltaZsigUpsilon,
                self.q))
        self.fitDataDeltaZtagUpsilon = ROOT.RooDataSet(
            "fitDataDeltaZtagUpsilon",
            "fitDataDeltaZtagUpsilon",
            ROOT.RooArgSet(
                self.DeltaZtagUpsilon,
                self.q))
 
        # Only for plotting
 
        self.TsigPosNeg = ROOT.RooRealVar("Tsig", "#it{t}_{sig}^{gen}", 0., 0., 7., "ps")
        self.TtagPosNeg = ROOT.RooRealVar("Ttag", "#it{t}_{tag}^{gen}", 0., 0., 7., "ps")
 

Member Function Documentation

event()

def event

(

self

)

Here the information is collected event by event.

Definition at line 395 of file B0_GenDeltaTFit.py.

terminate()

def terminate

(

self

)

Here the known quantum mechanical pdfs are defined and fitted to the generated MC distributions.
Afterwards, the plots are saved.

Definition at line 492 of file B0_GenDeltaTFit.py.

Member Data Documentation

Tsig

Tsig

Decay time of the signal B mesons.

Attention! This script recognizes only B0-> JPsiKs as signal B meson.

Definition at line 333 of file B0_GenDeltaTFit.py.

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The documentation for this class was generated from the following file:

• analysis/release-validation/CPVTools/B0_GenDeltaTFit.py