Radiohalos in a Radiochronological and Cosmological Perspective: Table 1.

Table 1. Comparison of sizes of induced bands (columns 1 to 5) with halo radii (columns 8 to 21). Column 6 gives the ⁴He ion energies at which the induced bands were formed, or the α-particle energies corresponding to the nuclides in column 7. Thus the nuclide or α-particle energy that produced any halo ring in columns 8 to 21 can be found from column 6 or 7. The letters K-L, H, S, M, and G represent halo measurements by Kerr-Lawson (15), Henderson (1, 6, 7), Schilling (9), Mahadevan (10), and Gentry. Subscripts L, M, and D indicate light, medium (dose 10 to 20 times coloration threshold), and dark (dose about 50 times coloration threshold) induced bands; L → D and L → M indicate light to dark and light to medium; these were visually determined. Gentry's measurements were made with a filar micrometer readable to 0.07 μm. The estimated overall uncertainty was ±0.3 μm. Other abbreviations: N.M., not measured; N.R., not resolved; N.P., not present.

Coloration band size (μm) E
(Mev) Nuclide U halo radius (μm) Polonium halo radius (μm) in

Biotite Fluo-
rite Cordi-
erite Biotite Fluorite Cordi-
erite Biotite Fluorite

²¹⁰Po ²¹⁴Po ²¹⁸Po ²¹⁰Po ²¹⁸Po

1. G_L 2. G_M 3. G_D 4. G 5. G 6. 7. 8. K-L 9. H 10. G 11. S 12. G 13. M 14. H 15. G_L→D 16. H 17. G_L→M 18. H 19. G_M 20. G 21. G

13.4 13.8 14.2 14.1 16.2
← 4.2

²³⁸U →
12.3 12.7 12.2→13.0 14.0 14.2 16 N.P. N.P. N.P. N.P. N.P. N.P. N.P. N.P.

N.M. 16.7 N.M. 17.3 19.2
← 4.77

²²⁶Ra →
15.4 15.3 14.8→15.8 16.9 17.1 19 N.P. N.P. N.P. N.P. N.P. N.P. N.P. N.P.

N.M. N.M. N.M. N.M. N.M.
← 4.66

²³⁰Th →
N.R. N.R. N.R. 15.8 N.R. N.R. N.P. N.P. N.P. N.P. N.P. N.P. N.P. N.P.

N.M. 16.7 N.M. 17.3 19.2
← 4.78

²³⁴U →
15.4 15.3 14.8→15.8 16.9 17.1 19 N.P. N.P. N.P. N.P. N.P. N.P. N.P. N.P.

N.M. 19.3 20.0 19.6 22.5
← 5.3

²¹⁰Po →
N.R. N.R. N.R. 19.3 19.5 N.R. 19.8 18.3→19.9 20.0 18.1→19.1 19.9 19.3 19.8 19.8

N.M. 20.5 21.1 N.M. N.M.
← 5.49

²²²Rn →
18.6 19.2 18.1→19.0 20.5 20.5 23.5 N.P. N.P. N.P. N.P. N.P. N.P. N.P. N.P.

N.M. 23.0 23.9 23.6 26.7
← 6.0

²¹⁸Po →
22.0 23.0 21.5→22.7 23.5 23.5 26.5 N.P. N.P. N.P. N.P. 24.0 23.3 N.P. 23.7

33.1 33.9 34.4 34.6 38.7
← 7.69

²¹⁴Po →
33.0 34.1 30.8→33.0 34.5 34.7 38.5 N.P. N.P. 34.5 32.5→33.8 34.0 34.0 N.P. 34.9