Rivet analyses
title: BELLE_2009_I817326
Differential branching ratio, polarization and asymmetries in $B\to K^{(*)}\ell^+\ell^-$
Experiment: BELLE (KEKB)
Inspire ID: 817326
Status: VALIDATED NOHEPDATA
Authors: - Peter Richardson
References: - Phys.Rev.Lett. 103 (2009) 171801
Beams: * *
Beam energies: ANY
Run details: - Any process production B0 and B+ mesons, oeiginally Upsilon(4S) decay
Measurement of the differential branching ratio, polarization and asymmetries in $B\to K^{(*)}\ell^+\ell^-$ as a function of $q^2$.
Source code:BELLE_2009_I817326.cc
```c++ // -- C++ --
include "Rivet/Analysis.hh"
include "Rivet/Projections/DecayedParticles.hh"
include "Rivet/Projections/UnstableParticles.hh"
namespace Rivet {
/// @brief B -> K(*) l+ l- class BELLE_2009_I817326 : public Analysis { public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BELLE_2009_I817326);
/// @name Analysis methods
/// @{
/// Book histograms and initialise projections before the run
void init() {
// Initialise and register projections
UnstableParticles ufs = UnstableParticles(Cuts::abspid == 511 or Cuts::abspid == 521);
declare(ufs, "UFS");
DecayedParticles BB(ufs);
BB.addStable(443);
BB.addStable(100443);
BB.addStable(PID::K0S);
BB.addStable(PID::K0L);
BB.addStable(313);
BB.addStable(-313);
BB.addStable(323);
BB.addStable(-323);
declare(BB, "BB");
for (unsigned int ix = 0; ix < 2; ++ix) {
book(_p_FL[ix], 1, 1 + ix, 2);
for (unsigned int iy = 0; iy < 2; ++iy) {
book(_h_br[ix][iy], 1 + ix, 1 + iy, 1);
book(_p_FB[ix][iy], 1 + ix, 1 + iy, 4);
for (unsigned int iz = 0; iz < 2; ++iz)
book(_h_br_B[ix][iy][iz],
"TMP/h_br_" + toString(ix + 1) + "_" + toString(iy + 1) + "_" + toString(iz + 1),
refData(1 + ix, 1 + iy, 1));
}
};
for (unsigned int ix = 0; ix < 3; ++ix) book(_c[ix], "TMP/c_" + toString(ix + 1));
}
/// Perform the per-event analysis
void analyze(const Event& event) {
static const map<PdgId, unsigned int>& mode1 = {{321, 1}, {13, 1}, {-13, 1}};
static const map<PdgId, unsigned int>& mode1CC = {{-321, 1}, {13, 1}, {-13, 1}};
static const map<PdgId, unsigned int>& mode2 = {{310, 1}, {13, 1}, {-13, 1}};
static const map<PdgId, unsigned int>& mode2CC = {{130, 1}, {13, 1}, {-13, 1}};
static const map<PdgId, unsigned int>& mode3 = {{321, 1}, {11, 1}, {-11, 1}};
static const map<PdgId, unsigned int>& mode3CC = {{-321, 1}, {11, 1}, {-11, 1}};
static const map<PdgId, unsigned int>& mode4 = {{310, 1}, {11, 1}, {-11, 1}};
static const map<PdgId, unsigned int>& mode4CC = {{130, 1}, {11, 1}, {-11, 1}};
static const map<PdgId, unsigned int>& mode5 = {{323, 1}, {13, 1}, {-13, 1}};
static const map<PdgId, unsigned int>& mode5CC = {{-323, 1}, {13, 1}, {-13, 1}};
static const map<PdgId, unsigned int>& mode6 = {{313, 1}, {13, 1}, {-13, 1}};
static const map<PdgId, unsigned int>& mode6CC = {{-313, 1}, {13, 1}, {-13, 1}};
static const map<PdgId, unsigned int>& mode7 = {{323, 1}, {11, 1}, {-11, 1}};
static const map<PdgId, unsigned int>& mode7CC = {{-323, 1}, {11, 1}, {-11, 1}};
static const map<PdgId, unsigned int>& mode8 = {{313, 1}, {11, 1}, {-11, 1}};
static const map<PdgId, unsigned int>& mode8CC = {{-313, 1}, {11, 1}, {-11, 1}};
DecayedParticles BB = apply<DecayedParticles>(event, "BB");
for (unsigned int ix = 0; ix < BB.decaying().size(); ++ix) {
_c[0]->fill();
if (BB.decaying()[ix].abspid() == 521)
_c[1]->fill();
else
_c[2]->fill();
int imode = 0;
if ((BB.decaying()[ix].pid() > 0 && BB.modeMatches(ix, 3, mode1))
|| (BB.decaying()[ix].pid() < 0 && BB.modeMatches(ix, 3, mode1CC)))
imode = 0;
else if (BB.modeMatches(ix, 3, mode2) || BB.modeMatches(ix, 3, mode2CC))
imode = 1;
else if ((BB.decaying()[ix].pid() > 0 && BB.modeMatches(ix, 3, mode3))
|| (BB.decaying()[ix].pid() < 0 && BB.modeMatches(ix, 3, mode3CC)))
imode = 2;
else if (BB.modeMatches(ix, 3, mode4) || BB.modeMatches(ix, 3, mode4CC))
imode = 3;
else if ((BB.decaying()[ix].pid() > 0 && BB.modeMatches(ix, 3, mode5))
|| (BB.decaying()[ix].pid() < 0 && BB.modeMatches(ix, 3, mode5CC)))
imode = 4;
else if ((BB.decaying()[ix].pid() > 0 && BB.modeMatches(ix, 3, mode6))
|| (BB.decaying()[ix].pid() < 0 && BB.modeMatches(ix, 3, mode6CC)))
imode = 5;
else if ((BB.decaying()[ix].pid() > 0 && BB.modeMatches(ix, 3, mode7))
|| (BB.decaying()[ix].pid() < 0 && BB.modeMatches(ix, 3, mode7CC)))
imode = 6;
else if ((BB.decaying()[ix].pid() > 0 && BB.modeMatches(ix, 3, mode8))
|| (BB.decaying()[ix].pid() < 0 && BB.modeMatches(ix, 3, mode8CC)))
imode = 7;
else
continue;
int il = imode < 2 || imode == 4 || imode == 5 ? 13 : 11;
const Particle& lp = BB.decayProducts()[ix].at(-il)[0];
const Particle& lm = BB.decayProducts()[ix].at(il)[0];
double qq = (lp.momentum() + lm.momentum()).mass2();
for (unsigned int iy = 0; iy < 2; ++iy) {
if (imode < 4) {
_h_br[1][iy]->fill(qq);
if (BB.decaying()[ix].abspid() == 521)
_h_br_B[1][iy][0]->fill(qq);
else
_h_br_B[1][iy][1]->fill(qq);
}
else {
_h_br[0][iy]->fill(qq);
if (BB.decaying()[ix].abspid() == 521)
_h_br_B[0][iy][0]->fill(qq);
else
_h_br_B[0][iy][1]->fill(qq);
}
}
// first boost to bottom frame
const LorentzTransform boost = LorentzTransform::mkFrameTransformFromBeta(
BB.decaying()[ix].momentum().betaVec());
FourMomentum plp = boost.transform(lp.momentum());
FourMomentum plm = boost.transform(lm.momentum());
FourMomentum pB = boost.transform(BB.decaying()[ix].momentum());
// lepton stuff
const LorentzTransform boost2 = LorentzTransform::mkFrameTransformFromBeta((plp + plm).betaVec());
plp = boost2.transform(plp);
double cTheta = plp.p3().unit().dot(boost.transform(pB).p3().unit());
double AFB = cTheta > 0 ? 1 : -1;
for (unsigned int iy = 0; iy < 2; ++iy) {
if (imode < 4)
_p_FB[1][iy]->fill(qq, AFB);
else
_p_FB[0][iy]->fill(qq, AFB);
}
// only K* for FL
if (imode < 4) continue;
int iK = BB.decaying()[ix].abspid() == 521 ? 323 : 313;
iK *= BB.decaying()[ix].pid() / BB.decaying()[ix].abspid();
const Particle& Kstar = BB.decayProducts()[ix].at(iK)[0];
FourMomentum pKstar = boost.transform(Kstar.momentum());
if (Kstar.children().size() != 2) continue;
Particle KK;
if (Kstar.abspid() == 313) {
if (Kstar.children()[0].abspid() == 321 && Kstar.children()[1].abspid() == 211)
KK = Kstar.children()[0];
else if (Kstar.children()[1].abspid() == 321 && Kstar.children()[0].abspid() == 211)
KK = Kstar.children()[1];
else
continue;
}
else {
if (Kstar.children()[0].abspid() == 311 && Kstar.children()[1].abspid() == 211)
KK = Kstar.children()[0];
else if (Kstar.children()[1].abspid() == 311 && Kstar.children()[0].abspid() == 211)
KK = Kstar.children()[1];
else if (Kstar.children()[0].abspid() == 310 && Kstar.children()[1].abspid() == 211)
KK = Kstar.children()[0];
else if (Kstar.children()[1].abspid() == 310 && Kstar.children()[0].abspid() == 211)
KK = Kstar.children()[1];
else if (Kstar.children()[0].abspid() == 321 && Kstar.children()[1].abspid() == 111 && il == 11)
KK = Kstar.children()[0];
else if (Kstar.children()[1].abspid() == 321 && Kstar.children()[0].abspid() == 111 && il == 11)
KK = Kstar.children()[1];
else
continue;
if (KK.abspid() == 311) {
if (KK.children().size() == 1 && KK.children()[0].pid() == 310)
KK = KK.children()[0];
else
continue;
}
}
FourMomentum pK = boost.transform(KK.momentum());
const LorentzTransform boost3 = LorentzTransform::mkFrameTransformFromBeta(pKstar.betaVec());
pK = boost3.transform(pK);
cTheta = pK.p3().unit().dot(boost.transform(pB).p3().unit());
double FL = .5 * (5. * sqr(cTheta) - 1.);
for (unsigned int iy = 0; iy < 2; ++iy) _p_FL[iy]->fill(qq, FL);
}
}
/// Normalise histograms etc., after the run
void finalize() {
// ratio of lifetimes
double rLife = 1. / 1.078;
for (unsigned int ix = 0; ix < 2; ++ix) {
for (unsigned int iy = 0; iy < 2; ++iy) {
scale(_h_br[ix][iy], 0.5e7 / *_c[0]);
for (unsigned int il = 0; il < 2; ++il) {
scale(_h_br_B[ix][iy][il], 0.5e7 / *_c[il + 1]);
if (il == 0) scale(_h_br_B[ix][iy][il], rLife);
}
// A_I plots
Estimate1DPtr AI;
book(AI, 1 + ix, 1 + iy, 3);
asymm(_h_br_B[ix][iy][1], _h_br_B[ix][iy][0], AI);
}
}
}
/// @}
/// @name Histograms
/// @{
Histo1DPtr _h_br[2][2], _h_br_B[2][2][2];
Profile1DPtr _p_FL[2], _p_FB[2][2];
CounterPtr _c[3];
/// @}
};
RIVET_DECLARE_PLUGIN(BELLE_2009_I817326);
} ```