The de-Broglie wavelength of a neutron in thermal equilibrium

The de-Broglie wavelength of a neutron in thermal equilibrium with heavy water at a temperature T (Kelvin) and mass m, is :-

We know that,
de-Broglie wavelength

λ =	h	=	h
	P		√2 m(KE)

K.E. of thermal neutron

=	3	kT
	2

=	h
	√2m(3/2 kT)

λ =	h
	√3 mkT

	h
	√3mKT

	2h
	√3mKT

	2h
	√mKT

	h
	√mKT