Could neutron flux from a hotter primary star/keep a brown dwarf burning?

Question

Brown dwarfs are the smallest class of star ranging from 13 to 80 times the mass of Jupiter, 0.01-0.08 solar masses; it is thought that they are stars only because fusion reactions involving hydrogen's heavy isotopes, deuterium and tritium, are possible at much lower temperatures and pressures than the proton-proton fusion of their heavier cousins the Red dwarfs. Brown Dwarfs are consequently thought to be quite short lived, burning through their heavy isotopes in a 100 million years or less before going cold.

Deuterium and Tritium can form through neutron capture but Hydrogen and Deuterium both have small neutron capture cross sections making the event unlikely under what might be considered normal circumstances.

Now the question, could hotter true stars in multi-star systems with low mass dwarf candidates produce enough neutron flux, and capture, to make a noticeable difference to the lifespan of their Brown Dwarf companions?

I'd like answers to take into account the temperature/flux range of known stars and assume a tight orbit similar to that of 51 Pegasi b for the Brown Dwarf candidate.

Answer 1

What's the odds that the two stars are close enough for a significant fraction of any neutrons to cross the gap? Remember that a free neutron has a rather short half-life of 10 minutes, and that the target star will span a small part of the arc of the sky, the extreme majority of particles would simply miss.

What sort of star gives significant levels of neutrons in the first place? The star would need to have fusion or fission right at the surface, in practice this means localized infrequent events like large solar flares.

So the Brown Dwarf receives a tiny fraction of the neutrons created by the larger star,
and those neutrons are only created by a tiny fraction of reactions on the parent star,
and many of those neutrons will decay while crossing the space between the stars.

The Brown dwarf will indeed receive an energy boost in fusables from the neutron flux of the bigger star, but it is a minuscule fraction of a minuscule fraction of a fraction of the total energy output of the bigger star.

The direct photonic illumination will be many magnitudes more relevant.

Answer 2

Seems unlikely because whatever capture is going on would likely be high in the brown dwarf's atmosphere in relation to the comparatively tiny fusion region.