The magnetic field at the centre of a current carrying circular loop of radius \( R \) is \( 16 \, \mu \text{T} \). The magnetic field at a distance \( x = \sqrt{3} R \) on its axis from the centre is ______ \( \mu \text{T} \).
\( 2 \)
\( 4 \)
\( 2\sqrt{2} \)
\( 8 \)