Calculate the effective neutron capture radius of a nucleus having a cross section of 1.0 barn.

Explanation

To calculate the effective neutron capture radius of a nucleus with a cross section of 1.0 barn, we can follow these steps:

### Step 1: Understand the Unit of Cross Section
The cross section is given in barns, where 1 barn is defined as \(1 \text{ barn} = 10^{-24} \text{ cm}^2\).

### Step 2: Convert Cross Section to Area
Since the cross section is given as 1.0 barn, we can convert it to square centimeters:
\[
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