Sibyll Production CS

[StFroese]

I am currently trying to generate prod cs for proton-proton interaction. When I call the cross_section it seem that the code end up in this lines.

chromo/src/chromo/models/sibyll.py

Lines 257 to 266 in e9310e8

	tot, el, inel, diff, _, _ = self._lib.sib_sigma_hp(sib_id, kin.ecm)
	return CrossSectionData(
	total=tot,
	elastic=el,
	inelastic=inel,
	diffractive_xb=diff[0],
	diffractive_ax=diff[1],
	diffractive_xx=diff[2],
	diffractive_axb=0,
	)

Which calls the sibyll hadron-proton subroutine, which does not return a production cross section.
As far as I know the prod cs is defines as:
$\sigma_{prod} = \sigma_{tot} - \sigma_{el} - \sigma_{qela}$

The quasi-elastic cs should be zero since this process does not include neuclei, right?

Can we do?

return CrossSectionData( 
     total=tot, 
     elastic=el, 
     inelastic=inel, 
     prod=inel, # just adding it here
     diffractive_xb=diff[0], 
     diffractive_ax=diff[1], 
     diffractive_xx=diff[2], 
     diffractive_axb=0, 
 ) 

Or is this not correct or will mess up some community wide nomenclature?

[StFroese]

@afedynitch can you check?

[StFroese]

Same for QGSJET I think:

chromo/src/chromo/models/qgsjet.py

Lines 277 to 285 in e9310e8

	gtot, gin, gel, gdp, gdt, bel = self._lib.cqgshh_ha_cs()
	return CrossSectionData(
	total=gtot,
	inelastic=gin,
	elastic=gel,
	diffractive_xb=gdp,
	diffractive_ax=gdt,
	b_elastic=bel,
	)

[StFroese]

This is a problem if one wants to compute the prod cs of a compisite target that contains protons for example.

chromo/src/chromo/common.py

Lines 804 to 816 in e9310e8

	with self._temporary_kinematics(kin):
	kin2 = self.kinematics
	if isinstance(kin2.p2, CompositeTarget):
	cross_section = CrossSectionData(0, 0, 0, 0, 0, 0, 0)
	kin3 = copy.copy(kin2)
	for component, fraction in zip(kin2.p2.components, kin2.p2.fractions):
	kin3.p2 = component
	# this calls cross_section recursively, which is fine
	cross_section._mul_radd(
	fraction, self._cross_section(kin3, max_info=max_info)
	)
	return cross_section
	return self._cross_section(kin, max_info=max_info)

the nans are summed