Cross section table file format


Common file header is as follows:
!filetype    xs <ia>
!fileversion <yyyymmdd>
!filedate    <dow> <mmm> <dd> <hh>:<mm>:<ss> <yyyy> 
#
# comment
#
where <ia> is the type of interaction, see following sections.
The usual file name extension is: .<ia>.xs.

Electromagnetic (EM) interactions

EM interactions comprise elastic scattering, excitation, and ionization. Cross sections can be total (TCS), single differential in energy (or angle) (SDCS), and double differential in both energy and angle.
The common cross section file header is followed by:
!target      <material>
where <material> specifies a generic material name or chemical composition. Targets can be atomic or molecular.

Total Cross Sections (TCS)

Interactions <ia>={'l,t' | 'x,t' | 'i,t' } are foreseen for total elastic scattering, excitation, and ionization, respectively.
The common EM interaction file header is followed by:
!projectile   <projectile>
!shell      <shell-number_1>
<E_proj> <sigma_xx/cm**2> [<E_loss>] 
...
!shell      <shell-number_n>
<E_proj> <sigma_xx/cm**2> [<E_loss>] 
Partial cross sections for the different atomic or molecular electronic shells of the target may be given. Use !shell 0 for the sum of all shells.
The projectile energy <E_proj> is given in MeV/u for ionic projectiles and in keV for the others.
The energy loss <E_loss> is the potential energy needed for the respective interaction. It is optional and makes sense for excitations and for the sum of all shells (!shell 0). It is expected in keV.

Single Differential Cross Sections (SDCS)

Ionization

Interaction <ia>={ 'i,s' } is foreseen for single (energy) differential ionization, i.e. secondary electron energy spectra.
The common EM cross section file header is followed by:
!projectile   <projectile>
!shell      <shell-number_1>
!eproj      <E_proj_1> [<E_loss>]  
<E_e-/keV> <dsigma_si/dE/cm**2/keV>  
...
!eproj      <E_proj_2> [<E_loss>]
<E_e-/keV> <dsigma_si/dE/cm**2/keV>  
...
!shell      <shell-number_n>
!eproj      <E_proj_1> [<E_loss>]
<E_e-/keV> <dsigma_si/dE/cm**2/keV>  
... 
Partial cross sections for the different atomic or molecular electronic shells of the target may be given. Use !shell 0 if the sum of all shells is given.
The projectile energy <E_proj> is given in MeV/u for ionic projectiles and in keV for the others.

Elastic Scattering

Interaction <ia>={ 'l,s' } is foreseen for elastic scattering angular distributions.
The common EM cross section file header is followed by:
!projectile   <projectile>
!shell      <shell-number_1>
!eproj      <E_proj_1>
<cos(theta)> <dsigma_sl/dOmega/cm**2/sr>  
...
!eproj      <E_proj_2>
<cos(theta)> <dsigma_sl/dOmega/cm**2/sr>  
...
!shell      <shell-number_n>
!eproj      <E_proj_1>
<cos(theta)> <dsigma_sl/dOmega/cm**2/sr>  
... 
Partial cross sections for the different atomic or molecular electronic shells of the target may be given. Use !shell 0 if the sum of all shells is given.
The projectile energy <E_proj> is given in MeV/u for ionic projectiles and in keV for the others.

Double Differential Cross Sections (DDCS)

Interaction <ia>={ 'l,d' | 'x,d' | 'i,d' } is foreseen for double differential (energy,angle) cross sections.
The common EM cross section file header is followed by:
!projectile   <projectile>

!shell      <shell-number_1>
!eproj      <E_proj_1_1> [<E_loss>]
!esec       <E_sec_1_1_1>
<cos(theta)> <dsigma_di/dE/dOmega/cm**2/keV/sr>  
...
!esec       <E_sec_1_1_2>
<cos(theta)> <dsigma_di/dE/dOmega/cm**2/keV/sr>  
...
!eproj      <E_proj_1_2> [<E_loss>]
!esec       <E_sec_1_2_1>
<cos(theta)> <dsigma_di/dE/dOmega/cm**2/keV/sr>  
...
!esec       <E_sec_1_2_2>
<cos(theta)> <dsigma_di/dE/dOmega/cm**2/keV/sr>  
...

!shell      <shell-number_2>
!eproj      <E_proj_2_1> [<E_loss>]
!esec       <E_sec_2_1_1>
<cos(theta)> <dsigma_di/dE/dOmega/cm**2/keV/sr>  
...
!esec       <E_sec_2_1_2>
<cos(theta)> <dsigma_di/dE/dOmega/cm**2/keV/sr>  
...
!eproj      <E_proj_2_2> [<E_loss>]
!esec       <E_sec_2_2_1>
<cos(theta)> <dsigma_di/dE/dOmega/cm**2/keV/sr>  
...
!esec       <E_sec_2_2_2>
<cos(theta)> <dsigma_di/dE/dOmega/cm**2/keV/sr>  
...
Partial cross sections for the different atomic or molecular electronic shells of the target may be given. Use !shell 0 for the sum of all shells.
The projectile energy <E_proj> is given in MeV/u for ionic projectiles and in keV for the others.
The secondary electron energy <E_sec> is given in keV.
The usual file name extension is .<ia>.xs. Some formal examples for total, single and double differential cross sections.
Last updated: M.Kraemer,
$Id: traxfmtxs.html,v 1.1 2011/03/23 10:11:35 kraemer Exp $