Thanks Robin,
> On 20 mei 2016, at 23:40, mix...@bigpond.com wrote:
>
> In reply to Stephen Cooke's message of Fri, 20 May 2016 12:04:22 +0200:
> Hi,
> [snip]
>> Is there a relationship between the cross-section for slow neutron capture
>> in particular nuclei and the nucleus excitation energy needed in the nucleus
>> to cause neutron spallation?
>>
>> For example B10 has a high neutron cross-section. Is there s relationship
>> between this and the energy needed for Neutron spallation from B11?
>
> That's what I would expect too. Nuclei with a high neutron capture
> cross-section
> really "want" to have that extra neutron, because they become much more
> stable.
> Conversely, removing the neutron from the new stable nucleus should be very
> difficult.
> Compare the neutron capture energy release with that of other nuclei. I would
> expect it to be larger.
>
> In this case, 10B+n => 11B + 11.454 MeV
>
> (That's a lot for a single particle capture reaction).
>
> Another high capture cross-section reaction is:-
>
> 3He+n => 4He + 20.578 MeV
>
> which is why He3 is used in some neutron detectors.
>
> Regards,
>
> Robin van Spaandonk
>
> http://rvanspaa.freehostia.com/project.html
>