Arturo Quirantes, Francisco J. Olmo, Hassah Lyamani, Lucas Alados-Arboledas: Correction factors for a total scatter/backscatter nephelometer
Journal of Quantitative Spectroscopy and Radiative Transfer 109, 1496-1503 (2008)  [doi:10.1016/j.jqsrt.2007.12.014]

ABSTRACT:  Total aerosol scattering and backscattering atmospheric values are typically obtained with an integrating nephelometer.  Due to desigtn limitations, measurements do not cover the foll (0º-180º) angular range, and correction factors are necessary.  The effect of angle cutoff is examined for a nomber of particle size distributions and refractive indices.  Scattering data for sub-micron particles can be corrected by the use of a modified Anderson approximation, while data for larger particle distributions can be approximated by a function of the effective size parameter.  Correction factors for the hemispheric backscatter ratio are found to be small if nonsphericity is assumed.  Such approximations will help more accurate corrections for angle range, particularly at large size parameter values.

Keywords: Light scattering; Atmospheric aerosols; Nephelometer; Anderson approximation