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We now describe the implementation of the neutrino scattering cross sections
and branching ratios into a nuclear reaction network that describes the time
rate of change of a target nucleus (I) by all possible interactions
(previously defined in the introduction) involving a single neutron, proton,
alpha-particle, or gamma-ray in either the incident (j) or exit (k)
channel to create the product nucleus (L). We also include reaction linkages
via the three weak interactions beta decay (beta-), positron decay
(beta+), and electron capture (E.C.).
Specifically, we concentrate on the
nuclear cross section (as a function of incident particle energy) that
describes the probability of producing nucleus L via the weak or strong and
electromagnetic reactions mentioned above.
The product of a charged or neutral
current cross section with an appropriate branching ratio provides for
enhancement of some of these "standard" reaction network linkages (as is the
case with all three neutral current reactions considered), although two of the
six charged current reactions have no analog to possible reaction linkages
within the standard reaction network.
Neutral Current Contributions
The product of the neutral current cross section sigma_neut and the appropriate
neutral current proton (Bp), neutron (Bn), or alpha-particle (Balpha) branching
ratio provide for enhancement of the three reverse reactions (gamma,p),
(gamma,n), and (gamma,alpha), respectively. These are analogous to
photodisintegration reactions in a standard reaction network.
Charged Current Contributions
The gamma-ray channel of the charged current interaction is a modification to
the beta decay or positron decay + E.C. rate. For the modification of the
positron rate, one must modify the rate that flows into target nucleus I, not
I itself.
The beta decay (beta-) rate out of target nucleus I should be modified by
addition of the product sigma_e- X B_gammabeta-.
The positron decay plus electron capture rate (beta+EC) flowing into target
nucleus I should be modified by addition of the product sigma_e+ X B_gammabeta+.
The product of sigma_e- X B_nbeta- is the cross section for the target nucleus
I to interact with a neutrino and eject an electron and a neutron. It is like a
(p,2n) reaction (except that no proton is absorbed and only one neutron is
ejected) and has no present analog in the standard reaction network.
The product of sigma_e- X B_pbeta- is the cross section for the target nucleus
I to interact with a neutrino and eject an electron and a proton. It makes the
same product nucleus as a (gamma,n) reaction but ejects a proton rather than a
neutron.
The product of sigma_e+ X B_nbeta+ is the cross section for the target nucleus
I to interact with an antineutrino and eject a positron and a neutron. It yields
the same product nucleus as a (gamma,p) reaction but makes a neutron rather
than a proton.
The product of sigma_e+ X B_pbeta+ is the cross section for the target nucleus
I to interact with an antineutrino and eject a positron and a proton. It is
like a (n,2p) reaction (except that no neutron is absorbed and only one proton
is ejected) and has no present analog in the standard reaction network.
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