FLUKA: OPT-PROD
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OPT-PROD
requests and controls production of Cherenkov, Transition and Scintillation
Radiation in specified materials
See also OPT-PROP, Chap. 12}.
For SDUM
= CERE-OFF: switches off Cherenkov production
WHAT(1-3): not used
WHAT(4-6): assignment to materials, see below
SDUM
= CERE-OFF
For SDUM
= TRD-OFF: switches off Transition Radiation production
WHAT(1-3): not used
WHAT(4-6): assignment to materials, see below
SDUM
= TRD-OFF
For SDUM
= SCIN-OFF: switches off Scintillation light production
WHAT(1-3): not used
WHAT(4-6): assignment to materials, see below
SDUM
= SCIN-OFF
For SDUM
= CERENKOV: switches on Cherenkov production and defines photon
energy range
WHAT(1)
= minimum Cherenkov photon emission energy in GeV
Default
: 2.07E-9 GeV (2.07 eV, corresponding to 600 nm)
WHAT(2)
= maximum Cherenkov photon emission energy in GeV
Default
: 4.96E-9 GeV (4.96 eV, corresponding to 250 nm)
WHAT(3)
: not used
WHAT(4-6): assignment to materials, see below
SDUM
= CERENKOV
For SDUM
= CEREN-WV: switches on Cherenkov production and defines photon
wavelength range
WHAT(1)
= minimum Cherenkov photon emission wavelength in cm
Default
: 2.50E-5 cm (250 nm, or 1.2E6 GHz)
WHAT(2)
= maximum Cherenkov photon emission wavelength in cm
Default
: 6.00E-5 cm (600 nm, or 5.E5 GHz)
WHAT(3)
: not used
WHAT(4-6): assignment to materials, see below
SDUM
= CEREN-WV
For SDUM
= CEREN-OM: switches on Cherenkov production and defines photon
angular frequency range
WHAT(1)
= minimum Cherenkov photon angular frequency omega
= 2 x pi x frequency (in rad/s)
Default
: 3.14E15 rad/s (corresponding to 600 nm)
WHAT(2)
= maximum Cherenkov photon angular frequency omega
= 2 x pi x frequency (in rad/s)
Default
: 7.53E15 rad/s (corresponding to 250 nm)
WHAT(3)
: not used
WHAT(4-6): assignment to materials, see below
SDUM
= CEREN-OM
For SDUM
= SCINTILL: switches on Scintillation Light production and
defines photon energy
WHAT(1)
= i-th scintillation photon emission energy in GeV (i_max =3,
see Note 4)
WHAT(2)
> 0: fraction of energy loss going into i-th scintillation
photon emission.
=< -100: forces to use a user routine (see SPHSPC, USFSCI)
>= -99.0 and =< 0.0: ignored
WHAT(3)
: time constant of scintillation light in seconds
WHAT(4-6): assignment to materials, see below
SDUM
= SCINTILL
For SDUM
= SCINT-WV: switches on Scintillation Light production and
defines photon wavelength
WHAT(1)
= i-th scintillation photon emission wavelength in cm (i_max =3,
see Note 4)
Default
: 2.50E-5 cm (250 nm, or 1.2E6 GHz)
WHAT(2)
> 0: fraction of energy loss going into i-th scintillation
photon emission
=< -100: forces to use a user routine (see SPHSPC, USFSCI)
>= -99.0 and =< 0.0: ignored
WHAT(3)
: time constant of scintillation light in seconds
WHAT(4-6): assignment to materials, see below
SDUM
= SCINT-WV
For SDUM
= SCINT-OM: switches on Scintillation Light production and
defines photon angular frequency range
WHAT(1)
= i-th scintillation photon emission angular frequency omega =
2 x pi x frequency (in rad/s), (i_max =3, see Note 4)
Default
: 3.14E15 rad/s (corresponding to 600 nm)
WHAT(2)
> 0: fraction of energy loss going into i-th scintillation
photon emission
=< -100: forces to use a user routine (see SPHSPC, USFSCI)
>= -99.0 and =< 0.0: ignored
WHAT(3)
: time constant of scintillation light in seconds
WHAT(4-6): assignment to materials, see below
SDUM
= SCINT-OM
For all previous SDUM
's:
WHAT(4)
= lower bound of the indices of materials in which the indicated
Cherenkov, Scintillation or TRD photon emission range is defined
From material WHAT(4)
...
Default
= 3
WHAT(5)
= upper bound of the indices of materials in which the indicated
Cherenkov or TRD photon emission range is defined
...To material WHAT(5)
...
Default
= WHAT(4)
WHAT(6)
= step length in assigning indices
...in step of WHAT(6)
Default
= 1
Default
: (option OPT-PROD not given): no Cherenkov, scintillation or TRD
photon production
Notes:
1) Optical photons such as those produced by Cherenkov effect
are distinguished by their FLUKA name (OPTIPHOT) and by
their FLUKA id number (-1), as shown in 5}.
2) To transport optical photons, it is necessary to define
the optical properties of the relevant materials by
means of option OPT-PROP. Users can also write their own
routines USRMED (which is called at every step and at
boundary crossings when activated with MAT-PROP) and FRGHNS
(which defines surface roughness).
3) The energy/wavelength/frequency range as defined
by OPT-PROD for Cherenkov photon production is not
necessarily the same as that defined for transport by means
of OPT-PROP. The default values, however, are the same.
4) In case of scintillation light, only monochromatic photons are
considered for the moment, with a maximum of 3 different lines. The
lines can be defined repeating i times the OPT-PROD card with
SDUM
= SCINTILL. The energy lost by ionizing particles is partially
spent to produce optical photons, according to the fraction entered
in what(2). The sum of what(2) for all OPT-PROD cards in a
given material must be <1 (usually much less).
Example:
OPT-PROD 2.E-9 3.E-9 0.0 16.0 17.0 0. CERENKOV
OPT-PROD 2.E-9 3.E-9 0.0 19.0 20.0 0. CERENKOV
OPT-PROD 3.E-5 6.E-5 0.0 18.0 22.0 2. CEREN-WV
OPT-PROD 3.14E15 6.28E15 0.0 21.0 0.0 0. CEREN-OM
OPT-PROP 3.E-5 5.E-5 6.E-5 16.0 22.0 0. WV-LIMIT
MAT-PROP 1.0 0.0 0.0 17. 21. 4. USERDIRE
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