evgen::ldm::Kaon2HiggsFlux Class Reference

Kaon2HiggsFlux class definiton Implementation of model taken from: https://arxiv.org/abs/1909.11670. More...

Inheritance diagram for evgen::ldm::Kaon2HiggsFlux:

Public Member Functions
	Kaon2HiggsFlux (fhicl::ParameterSet const &pset)
	Constructor. More...
	~Kaon2HiggsFlux ()
	Destructor. More...
bool	MakeFlux (const simb::MCFlux &flux, MeVPrtlFlux &higgs, double &weight) override
void	configure (const fhicl::ParameterSet &) override
	Interface for configuring the particular algorithm tool. More...
double	MaxWeight () override
Public Member Functions inherited from evgen::ldm::IMeVPrtlFlux
virtual	~IMeVPrtlFlux () noexcept=default
	Virtual Destructor. More...
	IMeVPrtlFlux (const fhicl::ParameterSet &pset)
Public Member Functions inherited from evgen::ldm::IMeVPrtlStage
virtual	~IMeVPrtlStage () noexcept
	Virtual Destructor. More...
	IMeVPrtlStage (const char *name)
TVector3	RandomUnitVector ()
double	GetRandom ()
const char *	Name ()

Private Attributes
double	fM
	Mass of Higgs [GeV]. More...
double	fMixingAngle
	Mixing angle of dark higgs. More...
bool	fKDAROnly
bool	fKDIFOnly
bool	fKDIFandBeamline
bool	fIgnoreParentDecayTime
double	fKPBR
double	fKLBR

Additional Inherited Members
Protected Member Functions inherited from evgen::ldm::IMeVPrtlFlux
TLorentzVector	BeamOrigin ()
double	EnuLab (double enucm, TLorentzVector meson_mom, TLorentzVector meson_pos)
Protected Attributes inherited from evgen::ldm::IMeVPrtlFlux
evgb::EvtTimeShiftI *	fTimeShiftMethod
TRotation	fBeam2Det
TVector3	fBeamOrigin
std::string	fSpillTimeConfig
Protected Attributes inherited from evgen::ldm::IMeVPrtlStage
CLHEP::HepRandomEngine *	fEngine
const char *	fName

Detailed Description

Kaon2HiggsFlux class definiton Implementation of model taken from: https://arxiv.org/abs/1909.11670.

Definition at line 48 of file Kaon2HiggsFlux_tool.cc.

Constructor & Destructor Documentation

evgen::ldm::Kaon2HiggsFlux::Kaon2HiggsFlux

(

fhicl::ParameterSet const &

pset

)

Constructor.

Definition at line 80 of file Kaon2HiggsFlux_tool.cc.

                                                           :
  IMeVPrtlStage("Kaon2HiggsFlux"), 
  IMeVPrtlFlux(pset) 
{
    this->configure(pset);

}

evgen::ldm::Kaon2HiggsFlux::~Kaon2HiggsFlux

(

)

Destructor.

Definition at line 90 of file Kaon2HiggsFlux_tool.cc.

{
}

Member Function Documentation

void evgen::ldm::Kaon2HiggsFlux::configure ( const fhicl::ParameterSet &  )

overridevirtual

Interface for configuring the particular algorithm tool.

Parameters

ParameterSet

The input set of parameters for configuration

Implements evgen::ldm::IMeVPrtlStage.

Definition at line 181 of file Kaon2HiggsFlux_tool.cc.

{
  fM = pset.get<double>("M");
  fMixingAngle = pset.get<double>("MixingAngle");
  fIgnoreParentDecayTime = pset.get<bool>("IgnoreParentDecayTime");
  fKDAROnly = pset.get<bool>("KDAROnly", false);
  fKDIFOnly = pset.get<bool>("KDIFOnly", false);
  fKDIFandBeamline = pset.get<bool>("KDIFandBeamline", false);

  // Throw exception for a bad mass value
  if (fM > Constants::Instance().kplus_mass - Constants::Instance().piplus_mass && 
      fM > Constants::Instance().klong_mass - Constants::Instance().pizero_mass) {
    throw cet::exception("Kaon2HiggsFlux Tool: BAD MASS. Configured mass (" + std::to_string(fM) +
         ") is larger than allowed for K+ (" + std::to_string(Constants::Instance().kplus_mass - Constants::Instance().piplus_mass) + ") and KL (" +
         std::to_string(Constants::Instance().klong_mass - Constants::Instance().pizero_mass) + " production.");
  } 

  fKPBR = KaonPlusBranchingRatio(fM, fMixingAngle);
  fKLBR = KaonLongBranchingRatio(fM, fMixingAngle);

  std::cout << "K+ branching ratio: " << fKPBR << std::endl;
  std::cout << "K0 branching ratio: " << fKLBR << std::endl;

}

bool evgen::ldm::Kaon2HiggsFlux::MakeFlux ( const simb::MCFlux &  flux, MeVPrtlFlux &  higgs, double &  weight  )

overridevirtual

Implements evgen::ldm::IMeVPrtlFlux.

Definition at line 214 of file Kaon2HiggsFlux_tool.cc.

                                                                                                {

  // make the kaon parent
  evgen::ldm::KaonParent kaon(flux);
  if (!kaon.kaon_pdg) return false; // parent wasn't a kaon

  // select on the kaon
  if (fKDAROnly && (kaon.mom.P() > 1e-3 || kaon.pos.Z() < 72000.)) return false; //selects KDAR from absorber only.
  if (fKDAROnly) std::cout << "FOUND KDAR\n";
  if (fKDIFOnly && (kaon.mom.P() <= 1e-3)){ // no KDAR allowed (from anywhere). Accepts KDIF from beamline or absorber.
    std::cout << "found KDAR, skipping to next event\n";
    return false;
  }
  if (fKDIFandBeamline && (kaon.mom.P() <= 1e-3 && kaon.pos.Z() >= 72000.)) return false; //allows for KDAR from decay-pipe, and any KDIF. This option is exactly orthogonal to "KDAROnly" option. 

  TLorentzVector Beam4 = BeamOrigin();
  // get position in detector frame
  higgs.pos_beamcoord = kaon.pos;
  higgs.pos = kaon.pos;
  higgs.pos.Transform(fBeam2Det);
  higgs.pos += Beam4;

  if (fIgnoreParentDecayTime) higgs.pos.SetT(Beam4.T());

  // get the momentum direction in the kaon parent rest frame
  double kaon_mass = kaon.mom.M();  
  double higs_mass = fM;
  double pion_mass = TDatabasePDG::Instance()->GetParticle(PionPdg(kaon.kaon_pdg))->Mass();

  // ignore if we can't make this higgs
  if (kaon_mass - pion_mass < higs_mass) return false;

  // isotropic decay
  TVector3 kaon_frame_momentum = RandomUnitVector() * higgs_momentum(kaon_mass, pion_mass, higs_mass);
  std::cout << "Rest frame higgs P: " <<  higgs_momentum(kaon_mass, pion_mass, higs_mass) << std::endl;

  // boost to lab frame
  TLorentzVector mom;
  mom.SetVectM(kaon_frame_momentum, higs_mass);
  mom.Boost(kaon.mom.BoostVector());

  higgs.mom_beamcoord = mom;
  // rotate to detector frame
  higgs.mom = mom;
  higgs.mom.Transform(fBeam2Det);

  higgs.kmom_beamcoord = kaon.mom;
  // also save the kaon momentum in the detector frame
  higgs.kmom = kaon.mom;
  higgs.kmom.Transform(fBeam2Det);

  // The weight is the importance weight times the branching-ratio weight 
  weight = kaon.weight / SMKaonBR(kaon.kaon_pdg);
  if (kaon.kaon_pdg == 130 /* KLong */) {
    weight = weight * fKLBR;
  }
  else { // KPlus or KMinus
    weight = weight * fKPBR;
  }

  // and save the secondary momentum
  higgs.sec = higgs.kmom - higgs.mom;
  higgs.sec_beamcoord = higgs.kmom_beamcoord - higgs.mom_beamcoord;

  // set the mixing
  higgs.C1 = fMixingAngle;
  higgs.mass = fM;

  higgs.kaon_pdg = kaon.kaon_pdg;
  higgs.generator = 0; // kDissonantHiggs
  higgs.secondary_pdg = PionPdg(kaon.kaon_pdg);
  higgs.equiv_enu = EnuLab(flux.fnecm, higgs.kmom, higgs.pos);

  return true;
}

double evgen::ldm::Kaon2HiggsFlux::MaxWeight ( )

overridevirtual

Implements evgen::ldm::IMeVPrtlStage.

Definition at line 206 of file Kaon2HiggsFlux_tool.cc.

                                 {
  // Weight comes from the NuMi importance weight -- max is 100 (add in an epsilon) 
  //
  // Also get the max BR
  return 100.0001 * std::max(fKPBR / SMKaonBR(321), fKLBR / SMKaonBR(130));
}

Member Data Documentation

bool evgen::ldm::Kaon2HiggsFlux::fIgnoreParentDecayTime

private

Definition at line 73 of file Kaon2HiggsFlux_tool.cc.

bool evgen::ldm::Kaon2HiggsFlux::fKDAROnly

private

Definition at line 70 of file Kaon2HiggsFlux_tool.cc.

bool evgen::ldm::Kaon2HiggsFlux::fKDIFandBeamline

private

Definition at line 72 of file Kaon2HiggsFlux_tool.cc.

bool evgen::ldm::Kaon2HiggsFlux::fKDIFOnly

private

Definition at line 71 of file Kaon2HiggsFlux_tool.cc.

double evgen::ldm::Kaon2HiggsFlux::fKLBR

private

Definition at line 77 of file Kaon2HiggsFlux_tool.cc.

double evgen::ldm::Kaon2HiggsFlux::fKPBR

private

Definition at line 76 of file Kaon2HiggsFlux_tool.cc.

double evgen::ldm::Kaon2HiggsFlux::fM

private

Mass of Higgs [GeV].

Definition at line 68 of file Kaon2HiggsFlux_tool.cc.

double evgen::ldm::Kaon2HiggsFlux::fMixingAngle

private

Mixing angle of dark higgs.

Definition at line 69 of file Kaon2HiggsFlux_tool.cc.

---

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

• Kaon2HiggsFlux_tool.cc