TABLE 6b

RADIONUCLIDES PRODUCED COSMOGENICALLY BY NEUTRON BOMBARDMENT OF ARGON -- PART I:

CHLORINE (36Cl), SULFUR (35S), AND ALUMINUM (26Al)

36Cl 35S 26Al
Half-life 3.08 × 105 years 87.9 days 7.4 × 105 years
Production Rate (atoms·cm-2·s-1)
Troposphere

Total Atmosphere

4 × 10-4

1.1 × 10-3

4.9 × 10-4

1.4 × 10-4

3.8 × 10-5

1.4 × 10-5

Global Inventory 1.4 × 104 kg 4.5 g (1 PBq) 1000 kg
Distribution (%)
Stratosphere

Troposphere

Biosphere/land surface

Mixed ocean layer

Deep ocean layer

Ocean sediments

0.0001

0.8

10.0

24.0

0.4

0

57.0

0.000006

29.0

0.014

69.0

0

0.00013

0.0000007

29.0

0.0014

0.007

0.007

Concentration

Stratosphere

Troposphere

Oceans



0.0048 Bq/kg air

0.00013 Bq/kg air

--

--

--

0.28 × 10-3



--

--

0.6 × 10-3

Main Radiation 714 keV 167 keV ß(+)1.17 MeV

1.88 MeV 1.81 MeV

1.6, 2.17 MeV from 511 keV

38Cl daughter isotope

Notes: (1) Inventory as of 1967.

TABLE 6b (continued)

RADIONUCLIDES PRODUCED COSMOGENICALLY BY NEUTRON BOMBARDMENT OF ARGON -- PART II:

SODIUM ( 22Na), PHOSPHORUS ( 32P AND 33P), AND SILICON( 32Si)

22Na 32P 33P 26Si
Half-life 2.62 years 14.28 days 24.4 days 280 years
Production Rate (atoms·cm-2·s-1)
Troposphere

Total Atmosphere

2.4 × 10-5

1.8 × 10-5

2.7 × 10-4

8.1 × 10-4

2.2 × 10-4

6.8 × 10-4

5.4 × 10-5

1.6 × 10-4

Global Inventory

Distribution (%)

Stratosphere

Troposphere

Biosphere/land surface

Mixed ocean layer

Deep ocean layer

Ocean sediments

1.9-2.0 kg



25.0

1.7

21.0

44.0

8.0

0

0.4 g



60.0

24.0

4.7

13.0

7.0

0

0.6 g (3PBq)



64.0

16.0

5.6

11.0

1.0

0

1.4 kg



0.19

0.011

29.0

0.35

68.0

2.8



Concentration
Stratosphere

Troposphere

Oceans

8.5 × 10-5 Bq/kg air

1 × 10-7 Bq/kg air

--

0.028 Bq/kg air

1 × 10-4 Bq/kg air

--

0.025 Bq/kg air

1 × 10-4 Bq/kg air

--

--

--

4.66 × 10-7 Bq/kg water

Main Radiation

+ 0.545 MeV

+ 1.82 MeV

1.275 MeV

511 keV

1.710 MeV 248 keV 210 keV
Notes: (1) Inventory as of 1967.

(2) Some distribution data total to greater than 100% because of rounding errors.