Chandrasekhar–Fermi method
Chandrasekhar–Fermi method  or CF method or Davis–Chandrasekhar–Fermi method is a method that is used to calculate the mean strength of the interstellar magnetic field that is projected on the plane of the sky. The method was described by Leverett Davis Jr in 1951 and independently by Subrahmanyan Chandrasekhar and Enrico Fermi in 1953. According to this method, the magnetic field  in the plane of the sky is given by

where  is the mass density,  is the line-of-sight velocity dispersion and  is the dispersion of polarization angles and  is an order unity factor, which is typically taken it to be . The method is also employed for prestellar molecular clouds. References

Astrophysics