Hℓ-⁡(η,ρ)=-ⅈ⁢ⅇ-π⁢η⁢ρℓ+1(2⁢ℓ+1)!⁢Cℓ⁡(η)⁢∫0∞(exp⁡(-ⅈ⁢(ρ⁢tanh⁡t-2⁢η⁢t))(cosh⁡t)2⁢ℓ+2+ⅈ⁢(1+t2)ℓ⁢exp⁡(-ρ⁢t+2⁢η⁢arctan⁡t))⁢ⅆ⁡t,