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/XsectionRatios [ Modules ]

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NAME

module XsectionRatios

NOTES

Computes and stores the ratios of the in-medium and vacuum BB -> BB + mesons cross sections (see M. Wagner et al., PRC 71, 034910 (2005).

XsectionRatios/flagScreen [ Global module-variables ]

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SOURCE

  logical, save :: flagScreen = .false.

PURPOSE

If .true. -- The in-medium screening is applied to the input cross section. If .false. -- No cross section modification .

XsectionRatios/flagInMedium [ Global module-variables ]

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SOURCE

  logical, save :: flagInMedium = .false.

PURPOSE

If .true. -- In-medium ratios are used to decide whether an event is accepted or not. If .false. -- The event is always accepted

XsectionRatios/flagTabulate [ Global module-variables ]

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SOURCE

  logical, save :: flagTabulate = .false.

PURPOSE

If .true. -- in-medium ratios are tabulated. If .false. -- in-medium ratios are read-in. (This flag is important only if flagInMedium = .true.)

XsectionRatios/shift0 [ Global module-variables ]

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SOURCE

  real, save :: shift0 = 0.

PURPOSE

Mass shift m-m^* (GeV) for using in elementary particle collision mode.

XsectionRatios/getSigmaScreened [ Functions ]

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NAME

real function getSigmaScreened(pair,sigma)

PURPOSE

Returns the in-medium screened cross section (mbarn). See P. Daniewlewicz, NPA 673, 375 (2000); Acta. Phys. Pol. B 33, 45 (2002) INPUT:

  • type(particle), dimension(1:2), intent(in) :: pair ! incoming particles
  • real, intent(in) :: sigma ! not screened cross section

XsectionRatios/getSigmaTotal [ Functions ]

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NAME

real function getSigmaTotal(pair)

PURPOSE

Returns the total in-medium cross section (mbarn). INPUT:

  • type(particle), dimension(1:2), intent(in) :: pair ! incoming particles

NOTES: The total in-medium pp cross section is used for all types of colliding baryons/antibaryons. Returns zero if there is at least one incoming meson.

XsectionRatios/getRatio [ Functions ]

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NAME

real function getRatio(pair)

PURPOSE

Computes the ratio of the in-medium cross section to the vacuum cross section. INPUT:

  • type(particle), dimension(1:2), intent(in) :: pair ! incoming particles

XsectionRatios/accept_event [ Functions ]

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NAME

logical function accept_event(pair,finalState)

PURPOSE

Accepts or rejects the event randomly, using the in-medium cross section ratios * returns .true. --- if the event is accepted * returns .false. --- if the event is rejected INPUT:

  • type(particle), dimension(1:2), intent(in) :: pair ! incoming particles
  • type(particle), dimension(:), intent(in) :: finalState ! outgoing particles
  • real, optional :: sqrts_ini ! initial sqrts of colliding pair ! (before modifications by a 3-body collision)

XsectionRatios/init [ Subroutines ]

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NAME

subroutine init

PURPOSE

Reads in input switches from namelist XsectionRatios_input.

XsectionRatios/XsectionRatios_input [ Namelists ]

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NAME

NAMELIST /XsectionRatios_input/

PURPOSE

Includes the switches:

XsectionRatios/TabulateRatio [ Subroutines ]

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NAME

subroutine TabulateRatio

PURPOSE

Tabulates the ratio sigma_med / sigma_vac as a function of srtsStar and mass shift (m-mStar).

XsectionRatios/Ratio [ Functions ]

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NAME

real function Ratio(srtsStar,mStar,mass)

PURPOSE

Compute the ratio of the in-medium and vacuum B_1 + B_2 -> B_3 + B_4 + M_5 + M_6 + M_7 + M_8 cross sections INPUT:

  • real, intent(in) :: srtsStar ! c.m. energy (GeV),
  • real, intent(in), dimension(:) :: mStar, mass ! Dirac and vacuum masses of all particles (GeV)

OUTPUT:

  • real :: Ratio ! ratio of the in-medium and vacuum cross sections

NOTES: The particles 1 and 2 are incoming baryons, the particles 3 and 4 are outgoing baryons, the particles M_5, ..., M_8 are outgoing mesons. The routine will compute one of the ratios: B_1 + B_2 -> B_3 + B_4, B_1 + B_2 -> B_3 + B_4 + M_5, ..., B_1 + B_2 -> B_3 + B_4 + M_5 + ...+ M_8 depending on the the size n of the arrays mStar and mass, which must be in the interval [4:8].

XsectionRatios/Ratio_BaB [ Functions ]

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NAME

real function Ratio_BaB(pair,finalState)

PURPOSE

Compute the ratio of the in-medium and vacuum cross sections baryon + antibaryon -> mesons INPUT:

  • type(particle), dimension(1:2), intent(in) :: pair ! incoming particles
  • type(particle), dimension(:), intent(in) :: finalState ! outgoing particles

OUTPUT:

  • real :: Ratio_BaB ! ratio of the in-medium and vacuum cross sections

NOTES: Maximum 6 mesons can be treated (otherwice returns Ratio_BaB=1.).