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Merged
valeriaRaffuzzi merged 5 commits into from
Mar 19, 2026
Merged

Fission energy release #197

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e0f0e44
Added fission * energy release as a cross section
ChasingNeutrons Feb 24, 2026
66f39c5
Merge branch 'develop' into kappa_fission
ChasingNeutrons Mar 3, 2026
c368354
Fixes
ChasingNeutrons Mar 3, 2026
7195090
Added MG energy per fission
ChasingNeutrons Mar 17, 2026
9f88c70
Fix to docs
ChasingNeutrons Mar 17, 2026
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2 changes: 2 additions & 0 deletions IntegrationTestFiles/mgMat2
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Expand Up @@ -25,3 +25,5 @@ fission (1.0 0.0 0.0 0.0);
chi (0.8 0.2 0.0 0.0);

nu (2.3 0.0 0.0 0.0);

kappa (202 193 180 200);
17 changes: 15 additions & 2 deletions NuclearData/Reactions/reactionMG/Tests/fissionMG_test.f90
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Expand Up @@ -17,8 +17,7 @@ module fissionMG_test
!!
real(defReal),dimension(*),parameter :: nu = [2.3_defReal, 2.0_defReal, 1.3_defReal]
real(defReal),dimension(*),parameter :: chi = [0.333333_defReal, 0.333333_defReal, 0.333334_defReal]


real(defReal),dimension(*),parameter :: kappa = [200.0_defReal, 203.0_defReal, 201.0_defReal]

contains

Expand Down Expand Up @@ -63,6 +62,7 @@ subroutine fissionMG_Build_And_Functionality()
! Test Misc functionality
@assertEqual(ZERO, reaction % releaseDelayed(1), TOL)
@assertEqual(ZERO, reaction % sampleDelayRate(2, rand),TOL )
@assertEqual(202.27_defReal, reaction % getKappa(7),1E-5)

! Test Release
@assertEqual(ZERO, reaction % releasePrompt(-2), TOL)
Expand All @@ -74,6 +74,19 @@ subroutine fissionMG_Build_And_Functionality()
call dictT % kill()
call reaction % kill()

! Restart and test with kappa data included
call dictT % init(3)
call dictT % store('numberOfGroups',3)
call dictT % store('chi', chi)
call dictT % store('nu',nu)
call dictT % store('kappa', kappa)

! Build data Deck and initialise
data % dict => dictT
call reaction % init(data, macroFission)
@assertEqual(203.0_defReal, reaction % getKappa(2), 1E-5)

end subroutine fissionMG_Build_And_Functionality


end module fissionMG_test
54 changes: 48 additions & 6 deletions NuclearData/Reactions/reactionMG/fissionMG_class.f90
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Expand Up @@ -22,18 +22,21 @@ module fissionMG_class
!! A special type of MG reaction that contains data related to fission
!!
!! At the moment it has no information about delayed emissions, shall be introduced
!! at a latter date.
!! at a later date.
!! Fission spectrum is independent of the energy group
!!
!! Public members:
!! data -> data for fissionMG [energyGroup, reaction (nu or chi)]
!! data -> data for fissionMG [energyGroup, reaction (nu, chi, or optionally kappa)]
!! hasKappa -> flag for whether there is energy per fission data
!!
!! Interface:
!! reactionMG interface
!! buildFromDict -> builds fissionMG from a SCONE dictionary
!! getKappa -> obtains the energy per fission in MeV
!!
type, public, extends(reactionMG) :: fissionMG
real(defReal),dimension(:,:),allocatable :: data
logical(defBool) :: hasKappa = .false.
contains
! Superclass procedures
procedure :: init
Expand All @@ -46,13 +49,19 @@ module fissionMG_class

! Local procedures
procedure :: buildFromDict
procedure :: getKappa

end type fissionMG

!!
!! Reaction indices
!!
integer(shortInt),parameter :: NU_DAT = 1, CHI_DAT = 2
integer(shortInt),parameter :: NU_DAT = 1, CHI_DAT = 2, KAPPA_DAT = 3

!!
!! Default value of kappa used if no data is provided
!!
real(defReal), private, parameter :: KAPPA_DEFAULT = 202.27 ! [MeV]

contains

Expand Down Expand Up @@ -216,9 +225,27 @@ subroutine buildFromDict(self, dict)

! Get number of groups
call dict % get(nG, 'numberOfGroups')

! Check if energy per fission is present and allocate space appropriately
if (dict % isPresent('kappa')) then

self % hasKappa = .true.
allocate(self % data(nG, 3))

! Get kappa
call dict % get(temp, 'kappa')
if(size(temp) /= ng) then
call fatalError(Here, 'Invalid number of values of kappa. Given: '// numToChar(size(temp)) // &
' Expected: ' // numToChar(nG))
end if
self % data(:,KAPPA_DAT) = temp

else

self % hasKappa = .false.
allocate(self % data(nG, 2))

! Allocate space
allocate(self % data(nG, 2))
end if

! Get nu
call dict % get(temp, 'nu')
Expand Down Expand Up @@ -246,6 +273,22 @@ subroutine buildFromDict(self, dict)

end subroutine buildFromDict

!!
!! Get the energy release from fission
!!
pure function getKappa(self, G) result(kappa)
class(fissionMG), intent(in) :: self
integer(shortInt), intent(in) :: G
real(defReal) :: kappa

if (self % hasKappa) then
kappa = self % data(G, KAPPA_DAT)
else
kappa = KAPPA_DEFAULT
end if

end function getKappa

!!
!! Cast reactionHandle pointer to fissionMG pointer
!!
Expand All @@ -270,5 +313,4 @@ pure function fissionMG_TptrCast(source) result(ptr)

end function fissionMG_TptrCast


end module fissionMG_class
17 changes: 17 additions & 0 deletions NuclearData/Reactions/uncorrelatedReactionCE/fissionCE_class.f90
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Expand Up @@ -54,6 +54,7 @@ module fissionCE_class
!! eLawPrompt -> Energy Law for the prompt fission neutrons
!! nuBarDelayed -> Delayed release table for incindent energy [MeV]
!! delayed -> Information about Delayed emission precursors
!! Q -> Q value for the reaction [MeV]
!!
!! Interface:
!! uncorrelatedReactionCE interface
Expand All @@ -65,6 +66,7 @@ module fissionCE_class
class(energyLawENDF), allocatable :: eLawPrompt
class(releaseLawENDF),allocatable :: nuBarDelayed
type(precursor),dimension(:),allocatable :: delayed
real(defReal) :: Q = ZERO

contains
! Superclass procedures
Expand All @@ -79,6 +81,7 @@ module fissionCE_class

! Type specific procedures
procedure :: buildFromACE
procedure :: getQ
end type fissionCE

contains
Expand Down Expand Up @@ -148,8 +151,21 @@ elemental subroutine kill(self)
deallocate(self % delayed)
end if

self % Q = ZERO

end subroutine kill

!!
!! Returns the Q-value
!!
pure function getQ(self) result(Q)
class(fissionCE), intent(in) :: self
real(defReal) :: Q

Q = self % Q

end function getQ

!!
!! Returns true if reaction is in Centre-Of-Mass frame
!!
Expand Down Expand Up @@ -349,6 +365,7 @@ subroutine buildFromACE(self, ACE, MT)
! Read basic data
call new_totalNU(self % nuBarTotal, ACE)
call new_energyLawENDF(self % eLawPrompt, ACE, MT)
self % Q = ACE % QforMT(MT)

! Read Delayed Data
if (withDelayed) then
Expand Down
3 changes: 3 additions & 0 deletions NuclearData/ceNeutronData/aceDatabase/aceNeutronDatabase_class.f90
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Expand Up @@ -937,6 +937,9 @@ subroutine init(self, dict, ptr, silent )

end if

! Obtain the energy per fission with which to scale fission heating
call dict % getOrDefault(self % H235, 'energyPerFission', 202.27_defReal)

! Get path to ACE library
call dict % get(aceLibPath,'aceLibrary')

Expand Down
53 changes: 37 additions & 16 deletions NuclearData/ceNeutronData/aceDatabase/aceNeutronNuclide_class.f90
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Expand Up @@ -41,14 +41,17 @@ module aceNeutronNuclide_class


! Grid location parameters
integer(shortInt), parameter :: TOTAL_XS = 1
integer(shortInt), parameter :: ESCATTER_XS = 2
integer(shortInt), parameter :: IESCATTER_XS = 3
integer(shortInt), parameter :: CAPTURE_XS = 4
integer(shortInt), parameter :: FISSION_XS = 5
integer(shortInt), parameter :: NU_FISSION = 6
integer(shortInt), parameter :: PROMPT_NU_FISSION = 7
integer(shortInt), parameter :: TOTAL_XS = 1
integer(shortInt), parameter :: ESCATTER_XS = 2
integer(shortInt), parameter :: IESCATTER_XS = 3
integer(shortInt), parameter :: CAPTURE_XS = 4
integer(shortInt), parameter :: FISSION_XS = 5
integer(shortInt), parameter :: NU_FISSION = 6
integer(shortInt), parameter :: KAPPA_XS = 7
integer(shortInt), parameter :: PROMPT_NU_FISSION = 8

integer(shortInt), parameter :: NON_FISSILE_SIZE = 4, &
FISSILE_SIZE = 8

!!
!! Groups data related to an MT reaction
Expand Down Expand Up @@ -437,10 +440,12 @@ elemental subroutine microXSs(self, xss, idx, f)
if (self % isFissile()) then
xss % fission = data(FISSION_XS, 2) * f + (ONE-f) * data(FISSION_XS, 1)
xss % nuFission = data(NU_FISSION, 2) * f + (ONE-f) * data(NU_FISSION, 1)
xss % kappaXS = data(KAPPA_XS, 2) * f + (ONE-f) * data(KAPPA_XS, 1)
xss % promptNuFission = data(PROMPT_NU_FISSION, 2) * f + (ONE-f) * data(PROMPT_NU_FISSION, 1)
else
xss % fission = ZERO
xss % nuFission = ZERO
xss % kappaXS = ZERO
xss % promptNuFission = ZERO
end if
end associate
Expand Down Expand Up @@ -486,10 +491,12 @@ subroutine getThXSs(self, xss, idx, f, E, kT, rand)
if (self % isFissile()) then
xss % fission = data(FISSION_XS, 2) * f + (ONE-f) * data(FISSION_XS, 1)
xss % nuFission = data(NU_FISSION, 2) * f + (ONE-f) * data(NU_FISSION, 1)
xss % kappaXS = data(KAPPA_XS, 2) * f + (ONE-f) * data(KAPPA_XS, 1)
xss % promptNuFission = data(PROMPT_NU_FISSION, 2) * f + (ONE-f) * data(PROMPT_NU_FISSION, 1)
else
xss % fission = ZERO
xss % nuFission = ZERO
xss % fission = ZERO
xss % nuFission = ZERO
xss % kappaXS = ZERO
xss % promptNuFission = ZERO
end if

Expand Down Expand Up @@ -560,10 +567,12 @@ subroutine getUrrXSs(self, xss, idx, f, E, xi)
if (self % isFissile()) then
xss % fission = data(FISSION_XS, 2) * f + (ONE-f) * data(FISSION_XS, 1)
xss % nuFission = data(NU_FISSION, 2) * f + (ONE-f) * data(NU_FISSION, 1)
xss % kappaXS = data(KAPPA_XS, 2) * f + (ONE-f) * data(KAPPA_XS, 1)
xss % promptNuFission = data(PROMPT_NU_FISSION, 2) * f + (ONE-f) * data(PROMPT_NU_FISSION, 1)
else
xss % fission = ZERO
xss % nuFission = ZERO
xss % fission = ZERO
xss % nuFission = ZERO
xss % kappaXS = ZERO
xss % promptNuFission = ZERO
end if

Expand Down Expand Up @@ -594,6 +603,7 @@ subroutine getUrrXSs(self, xss, idx, f, E, xi)

if (self % isFissile()) then
xss % nuFission = xss % nuFission/xss % fission * val(3)
xss % kappaXS = xss % kappaXS / xss % fission * val(3)
xss % promptNuFission = xss % promptNuFission/xss % fission * val(3)
xss % fission = val(3)
end if
Expand Down Expand Up @@ -733,6 +743,7 @@ subroutine init(self, ACE, nucIdx, database)
top, firstIdxMT4
real(defReal), dimension(:), allocatable :: xsMT4
type(stackInt) :: scatterMT, absMT
real(defReal) :: H_Q
character(100), parameter :: Here = "init (aceNeutronNuclide_class.f90)"

! Reset nuclide just in case
Expand All @@ -753,9 +764,9 @@ subroutine init(self, ACE, nucIdx, database)

! Allocate space for main XSs
if (self % isFissile()) then
N = 7
N = FISSILE_SIZE
else
N = 4
N = NON_FISSILE_SIZE
end if

allocate(self % mainData(N, Ngrid))
Expand Down Expand Up @@ -815,10 +826,20 @@ subroutine init(self, ACE, nucIdx, database)
call self % fission % init(ACE, N_f)
end if

! Calculate nuFission
! Obtain Heating/Q scaling ratio
! Check if database is associated in order to satisfy tests where it might not be!
if (associated(database)) then
H_Q = database % H235 / database % Q235
else
H_Q = ONE
end if

! Calculate nuFission and kappaXS
do i = bottom, Ngrid
self % mainData(NU_FISSION,i) = self % mainData(FISSION_XS,i) * &
self % fission % release(self % eGrid(i))
self % mainData(NU_FISSION,i) = self % mainData(FISSION_XS,i) * &
self % fission % release(self % eGrid(i))
self % mainData(KAPPA_XS,i) = self % mainData(FISSION_XS,i) * &
self % fission % getQ() * H_Q
self % mainData(PROMPT_NU_FISSION,i) = self % mainData(FISSION_XS,i) * &
self % fission % releasePrompt(self % eGrid(i))
end do
Expand Down
6 changes: 6 additions & 0 deletions NuclearData/ceNeutronData/ceNeutronDatabase_inter.f90
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Expand Up @@ -39,6 +39,8 @@ module ceNeutronDatabase_inter
!!
!! Public Members:
!! mapDBRCnuc -> map to link indexes of DBRC nuclides with their corresponding 0K
!! H235 -> heating fission of U235, used for scaling fission energy
!! Q235 -> Q-value of U235 fission, used for scaling fission energy
!!
!! Interface:
!! nuclearDatabase Interface
Expand All @@ -53,6 +55,10 @@ module ceNeutronDatabase_inter
!!
type, public, abstract, extends(nuclearDatabase) :: ceNeutronDatabase
type(intMap) :: mapDBRCnuc

! Default fission scaling [MeV]
real(defReal) :: H235 = 202.27_defReal
real(defReal) :: Q235 = 193.406_defReal

contains

Expand Down
4 changes: 4 additions & 0 deletions NuclearData/mgNeutronData/baseMgNeutron/Tests/baseMgNeutronDatabase_iTest.f90
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Expand Up @@ -114,6 +114,7 @@ subroutine testBaseMgNeutronDatabaseWithP0()
@assertEqual(1.0_defReal, xss % capture, TOL)
@assertEqual(1.0_defReal, xss % fission, TOL)
@assertEqual(2.3_defReal, xss % nuFission, TOL)
@assertEqual(202.0_defReal, xss % kappaXS, TOL)

matClass => baseMgNeutronMaterial_CptrCast(database % getMaterial(1))
@assertTrue(associated(matClass), "Type Ptr Cast has failed")
Expand All @@ -127,6 +128,7 @@ subroutine testBaseMgNeutronDatabaseWithP0()
@assertEqual(4.0_defReal, xss % capture, TOL)
@assertEqual(0.0_defReal, xss % fission, TOL)
@assertEqual(0.0_defReal, xss % nuFission, TOL)
@assertEqual(0.0_defReal, xss % kappaXS, TOL)

! Get some invalid Materials
mat => baseMgNeutronMaterial_TptrCast(database % getMaterial(0))
Expand Down Expand Up @@ -243,6 +245,7 @@ subroutine testBaseMgNeutronDatabaseWithP1()
@assertEqual(1.0_defReal, xss % capture, TOL)
@assertEqual(1.0_defReal, xss % fission, TOL)
@assertEqual(2.3_defReal, xss % nuFission, TOL)
@assertEqual(202.0_defReal, xss % kappaXS, TOL)

matClass => baseMgNeutronMaterial_CptrCast(database % getMaterial(1))
@assertTrue(associated(matClass), "Type Ptr Cast has failed")
Expand All @@ -256,6 +259,7 @@ subroutine testBaseMgNeutronDatabaseWithP1()
@assertEqual(4.0_defReal, xss % capture, TOL)
@assertEqual(0.0_defReal, xss % fission, TOL)
@assertEqual(0.0_defReal, xss % nuFission, TOL)
@assertEqual(0.0_defReal, xss % kappaXS, TOL)

! Get some invalid Materials
mat => baseMgNeutronMaterial_TptrCast(database % getMaterial(0))
Expand Down
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