Is the fragmentation of Carbon ions mainly composed of alpha particles?

[alangne1]

I'm analyzing data taken from 500 MeV/nucleon Iron beam and 290 MeV/nucleon Carbon beam. When looking at the fragmentation that has occured, the fragmentation for the Carbon beam seems almost always be alpha particles (I though I would see some Beryllium as well). Does this mean that the Carbon nucleus is essentially just three alpha particles?

 

[Norman]

Alangne,

Assuming you are only looking at projectile fragmentation, have you compared your data with that of Zeitlin et al., who also looked at 290 MeV/n Carbon on 6 different targets?
http://prc.aps.org/abstract/PRC/v76/i1/e014911

If you look at the paper, while their analysis was fairly difficult, they were able to compute the different fragmentation cross sections (summed over isotope for a given charge). You will see in that paper that the 3 He breakup cross section is not the largest, though it is large. For instance, the Z=3 cross section was larger. The Z=3 channel happens to include the 2 He production data also, however. This is due to the type of detector they were using. The Z=3 data and the 2 He data completely overlap and are very difficult to untangle.

Again, I am not sure what your experimental setup was so don't know if you are talking exclusive or inclusive reactions here. The Zeitlin et al. paper is for inclusive total cross sections.

Cheers,
Norman