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/mesonHyperon [ Modules ]

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NAME

module mesonHyperon

PURPOSE

Includes the cross sections for nonstrange meson - Hyperon inelastic scattering. Public routines:


mesonHyperon/mesonY [ Subroutines ]

[ Top ] [ mesonHyperon ] [ Subroutines ]

NAME

subroutine mesonY(srts,teilchenIN,mediumATcollision,momentumLRF,teilchenOUT,sigmaTot,sigmaElast,plotFlag)

PURPOSE

Evaluates Y pi -> Y^*, Lambda eta -> Lambda(1670), Y^* pi -> Y^*, Y pi -> Kbar N and Y^* pi -> Kbar N

                 as well as 

Ybar pi -> Y^*bar, LambdaBar eta -> antiLambdaBar(1670), Y^*bar pi -> Y^*bar, Ybar pi -> K Nbar and Y^*bar pi -> K Nbar cross sections and returns also a "preevent"

INPUTS

  • real, intent(in) :: srts ! sqrt(s) in the process
  • type(particle),dimension(1:2), intent(in) :: teilchenIn ! colliding particles
  • type(medium), intent(in) :: mediumATcollision ! Medium informations at the position of the collision
  • real, intent(in) ,dimension(0:3) :: momentumLRF ! Total Momentum in LRF

Debugging:

  • logical, intent(in),optional :: plotFlag ! Switch on plotting of the Xsections

OUTPUT

  • real, intent(out) :: sigmaTot ! total Xsection
  • real, intent(out) :: sigmaElast ! elastic Xsection

This routine does a Monte-Carlo-decision according to the partial cross sections to decide on a final state with maximal 2 final state particles. These are returned in the vector teilchenOut. The kinematics of these teilchen is only fixed in the case of a single produced resonance. Otherwise the kinematics still need to be established. The result is:

  • type(preEvent),dimension(1:3), intent(out) :: teilchenOut ! outgoing particles

The cross sections are based on parameterization by M. Effenberger.

NOTES

Possible final states are :


mesonHyperon/evaluateXsections [ Subroutines ]

[ Top ] [ mesonHyperon ] [ Subroutines ]

NAME

subroutine evaluateXsections

PURPOSE

Evaluates Y(Y^*) pi -> Y^* and Y(Y^*) pi -> Kbar N cross sections.

NOTES

There is a resonance contribution to Y(Y^*) pi scattering.


mesonHyperon/init [ Subroutines ]

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NAME

subroutine init

PURPOSE

Discretises the backgrond cross sections for Y pi -> Kbar N


mesonHyperon/makeDecision [ Subroutines ]

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NAME

subroutine makeDecision

PURPOSE

Chooses randomly one of possible outgoing channels in meson-hyperon collision. Outgoing channels are: Y^* and Kbar N. Also the charges of outgoing particles are selected.


mesonHyperon/makeOutput [ Subroutines ]

[ Top ] [ mesonHyperon ] [ Subroutines ]

NAME

subroutine makeOutput

PURPOSE

Writes all cross sections to file as function of srts and plab [GeV] . Filenames:

  • 'mesonY_sigTotElast.dat' : sigmaTot, sigmaElast
  • 'mesonY_KbarN.dat' : Kbar Nucleon outgoing channel (summed
  • over final isospins)
  • 'pionLambda_KbarN.dat' : pi Lambda -> Kbar N isospin averaged
  • 'pionSigma_KbarN.dat' : pi Sigma -> Kbar N isospin averaged


mesonHyperon/evaluateResContr [ Subroutines ]

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NAME

subroutine evaluateResContr(sigmaElast_res,sigmaKbarN_res)

PURPOSE

Computes elastic cross section Y (Y^*) pi -> Y (Y^*) pi and Kbar N production (final isospin sum) Y (Y^*) pi -> Kbar N due to intermediate resonances

OUTPUT

  • real, intent(out) :: sigmaElast_res ! resonance contribution to the elastic Xsection
  • real, intent(out) :: sigmaKbarN_res ! resonance contribution to the Kbar N production cross section summed over final isospins