Heitler London Method: What Do S & T Mean?

[LagrangeEuler]

http://books.google.rs/books?id=vrc...epage&q=Nolting Heitler London method&f=false

What means labels s and t on page 189. formula 5.37
|\psi_s\rangle=|q\rangle^{(+)}|0;0\rangle
|\psi_t\rangle=|q\rangle^{(-)}|1;m_s\rangle
?

 

[Bill_K]

s stands for singlet (antisymmetric) and t stands for triplet (symmetric)

 

[LagrangeEuler]

Tnx. One more question. Is it mistake in relations 5.38?

(\frac{p_1^2}{2m}-\frac{e^2}{2\pi\epsilon_0r_{1a}})|\psi_a^{(1)} \rangle=E_a|\psi_a^{(1)}\rangle

Why not

(\frac{p_1^2}{2m}-\frac{e^2}{4\pi\epsilon_0r_{1a}})|\psi_a^{(1)} \rangle=E_a|\psi_a^{(1)}\rangle
?