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changed constant for mass of neutron in MeV/c^2 and modified inverse-velocity documentation

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This commit is contained in:
Sam Shaner 2015-10-23 18:54:36 -04:00
parent 8ff4866020
commit 6038733a22
3 changed files with 28 additions and 23 deletions
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15
docs/source/usersguide/input.rst
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@ -1390,9 +1390,11 @@ The ``<tally>`` element accepts the following sub-elements:
"events". These correspond to the following physical quantities:
:flux:
Total flux in particle-cm per source particle. Note: The ``analog``
estimator is actually identical to the ``collision`` estimator for the
flux score.
Total flux in particle-cm per source particle.
.. note::
The ``analog`` estimator is actually identical to the ``collision``
estimator for the flux score.
:total:
Total reaction rate in reactions per source particle.
@ -1480,8 +1482,11 @@ The ``<tally>`` element accepts the following sub-elements:
:inverse-velocity:
The flux-weighted inverse velocity where the velocity is in units of
meters per second. Note: The ``analog`` estimator is actually identical
to the ``collision`` estimator for the inverse-velocity score.
meters per second.
.. note::
The ``analog`` estimator is actually identical to the ``collision``
estimator for the inverse-velocity score.
:events:
Number of scoring events. Units are events per source particle.

32
src/constants.F90
View file

@ -60,22 +60,22 @@ module constants
! Values here are from the Committee on Data for Science and Technology
! (CODATA) 2010 recommendation (doi:10.1103/RevModPhys.84.1527).
real(8), parameter :: &
PI = 3.1415926535898_8, & ! pi
MASS_NEUTRON = 1.008664916_8, & ! mass of a neutron in amu
MASS_PROTON = 1.007276466812_8, & ! mass of a proton in amu
AMU = 1.660538921e-27_8, & ! 1 amu in kg
AMU_MEV = 931.494061_8, & ! 1 amu in MeV/c^2
C_LIGHT = 2.99792458e8_8, & ! speed of light in a vacuum
N_AVOGADRO = 0.602214129_8, & ! Avogadro's number in 10^24/mol
K_BOLTZMANN = 8.6173324e-11_8, & ! Boltzmann constant in MeV/K
INFINITY = huge(0.0_8), & ! positive infinity
ZERO = 0.0_8, &
HALF = 0.5_8, &
ONE = 1.0_8, &
TWO = 2.0_8, &
THREE = 3.0_8, &
FOUR = 4.0_8
real(8), parameter :: &
PI = 3.1415926535898_8, & ! pi
MASS_NEUTRON = 1.008664916_8, & ! mass of a neutron in amu
MASS_NEUTRON_MEV = 939.565379_8, & ! mass of a neutron in MeV/c^2
MASS_PROTON = 1.007276466812_8, & ! mass of a proton in amu
AMU = 1.660538921e-27_8, & ! 1 amu in kg
C_LIGHT = 2.99792458e8_8, & ! speed of light in a vacuum
N_AVOGADRO = 0.602214129_8, & ! Avogadro's number in 10^24/mol
K_BOLTZMANN = 8.6173324e-11_8, & ! Boltzmann constant in MeV/K
INFINITY = huge(0.0_8), & ! positive infinity
ZERO = 0.0_8, &
HALF = 0.5_8, &
ONE = 1.0_8, &
TWO = 2.0_8, &
THREE = 3.0_8, &
FOUR = 4.0_8
! ============================================================================
! GEOMETRY-RELATED CONSTANTS

4
src/tally.F90
View file

@ -140,11 +140,11 @@ contains
score = p % last_wgt
end if
score = score / material_xs % total &
/ (sqrt(2 * p % E / (MASS_NEUTRON * AMU_MEV)) * C_LIGHT)
/ (sqrt(TWO * p % E / (MASS_NEUTRON_MEV)) * C_LIGHT)
else
! For inverse velocity, we need no cross section
score = flux / (sqrt(2 * p % E / (MASS_NEUTRON * AMU_MEV)) * C_LIGHT)
score = flux / (sqrt(TWO * p % E / (MASS_NEUTRON_MEV)) * C_LIGHT)
end if