coding lsqnonlin with multiple variables

Hello, I would like to fit the curve of following formula.

I want to optimize parameters (A, Tb, tau, n, alpha_g, c1, c2) with lsqnonlin. The independent variables are T and alpha. (The dependent variable is eta)

I have experimental data of T, alpha about T, and eta about T.

Please help if somebody have experience about this.

Thanks in Advance.