Control of the physical processes

For most of the individual processes the default option (indicated below) can be changed via data records [BASE040]. The processes are controlled via a control variable which is in the common /GCKING/. If not otherwise noted, the meaning of the control variable is the following:

= 0

The process is completely ignored.

= 1

The process is considered and possible secondary particles generating from the interaction are put into the /GCKING/ common. If the interacting particle disappears in the interaction, then it is stopped with ISTOP=1 (common /GCTRAK/)

= 2

The process is considered. If secondary particles result from the interaction, they are not generated and their energy is simply added in the variable DESTEP (common /GCTRAK/. If the interacting particle disappears in the interaction, the variable ISTOP is set to 2.

Keyword

Related process

DCAY

Decay in flight. The decaying particles stops. The variable IDCAY controls this process.

IDCAY =0

No decay in flight.

=1

( D) Decay in flight with generation of secondaries.

=2

Decay in flight without generation of secondaries.

MULS

Multiple scattering. The variable IMULS controls this process.

IMULS =0

No multiple scattering.

=1

( D) Multiple scattering according to Molière theory.

=2

Same as 1. Kept for backward compatibility.

=3

Pure Gaussian scattering according to the Rossi formula.

PFIS

Nuclear fission induced by a photon. The photon stops. The variable IPFIS controls this process.

IPFIS =0

( D) No photo-fission.

=1

Photo-fission with generation of secondaries.

=2

Photo-fission without generation of secondaries.

MUNU

Muon-nucleus interactions. The muon is not stopped. The variable IMUNU controls this process.

IMUNU =0

No muon-nucleus interactions.

=1

( D) Muon-nucleus interactions with generation of secondaries.

=2

Muon-nucleus interactions without generation of secondaries.

LOSS

Continuous energy loss. The variable ILOSS controls this process.

ILOSS =0

No continuous energy loss,IDRAY is forced to 0.

=1

Continuous energy loss with generation of $\delta$ -rays above DCUTE (common /GCUTS/) and restricted Landau fluctuations below DCUTE.

=2

( D) Continuous energy loss without generation of $\delta$ -rays and full Landau-Vavilov-Gauss fluctuations. In this case the variable IDRAY is forced to 0 to avoid double counting of fluctuations.

=3

Same as 1, kept for backward compatibility.

=4

Energy loss without fluctuation. The value obtained from the tables is used directly.

PHOT

Photoelectric effect. The interacting photon is stopped. The variable IPHOT controls this process.

IPHOT =0

No photo-electric effect.

=1

( D) Photo-electric effect with generation of the electron.

=2

Photo-electric effect without generation of the electron.

COMP

Compton scattering. The variable ICOMP controls this process.

ICOMP =0

No Compton scattering.

=1

( D) Compton scattering with generation of .

=2

Compton scattering without generation of .

PAIR

Pair production. The interacting $\gamma$ is stopped. The variable IPAIR controls this process.

IPAIR =0

No pair production.

=1

( D) Pair production with generation of /.

=2

Pair production without generation of /.

BREM

bremsstrahlung. The interacting particle (, , $\mu +$ , $\mu -$ ) is not stopped. The variable IBREM controls this process.

IBREM =0

No bremsstrahlung.

=1

( D) bremsstrahlung with generation of $\gamma$ .

=2

bremsstrahlung without generation of $\gamma$ .

RAYL

Rayleigh effect. The interacting $\gamma$ is not stopped. The variable IRAYL controls this process.

IRAYL =0

( D) No Rayleigh effect.

=1

Rayleigh effect.

DRAY

$\delta$ -ray production. The variable IDRAY controls this process.

IDRAY =0

No $\delta$ -rays production.

=1

( D) $\delta$ -rays production with generation of .

=2

$\delta$ -rays production without generation of .

ANNI

Positron annihilation. The is stopped. The variable IANNI controls this process.

IANNI =0

No positron annihilation.

=1

( D) Positron annihilation with generation of photons.

=2

Positron annihilation without generation of photons.

HADR

Hadronic interactions. The particle is stopped in case of inelastic interaction, while it is not stopped in case of elastic interaction. The variable IHADR controls this process.

IHADR =0

No hadronic interactions.

=1

( D) Hadronic interactions with generation of secondaries.

=2

Hadronic interactions without generation of secondaries.

>2

Can be used in the user code GUPHAD and GUHADR to chose a hadronic package. These values have no effect on the hadronic packages themselves.

LABS

Light ABSorption. This process is the absorption of light photons (particle type 7) in dielectric materials. It is turned on by default when the generation of Cerenkov light is requested (data record CKOV). For more information see [PHYS260].

ILABS =0

No absorption of photons.

=1

Absorption of photons with possible detection.

STRA

This flag turns on the collision sampling method to simulate energy loss in thin materials, particularly gases. For more information see [PHYS334].

ISTRA =0

( D) Collision sampling switched off.

=1

Collision sampling activated.

SYNC

Synchrotron radiation in magnetic field.

ISYNC =0

( D) The synchrotron radiation is not simulated.

=1

Synchrotron photons are generated, at the end of the tracking step.

=2

Photons are not generated, the energy is deposit locally.

=3

Synchrotron photons are generated, distributed along the curved path of the particle.

M. Maire, F.Carminati

PHYS010