qspec.a_tilda  (  i ,  j_l ,  f_l ,  j_u ,  f_u ,  as_sympy = False  )[source]

The relative peak strength in a hyperfine structure spectrum $$f_F^{F^\prime} = (2F_l + 1)(2F_u + 1) \begin{Bmatrix} J_u & J_l & 1 \\ F_l & F_u & I \end{Bmatrix}^2,$$ as used in TILDA.

Parameters:

isympy_quant

The nuclear spin quantum number $I$.

j_lsympy_quant

The electronic total angular momentum quantum number $J_l$ of the lower state.

f_lsympy_quant

The total angular momentum quantum number $F_l$ of the lower state.

j_usympy_quant

The electronic total angular momentum quantum number $J_u$ of the upper state.

f_usympy_quant

The total angular momentum quantum number $F_u$ of the upper state.

as_sympybool

Return the result as a symbol (True) or as a float (False).

Returns:

outsympy_core | float

The relative peak strength $f_F^{F^\prime}$.