In this Letter, we exploit the polarization property of light to investigate the Ångström exponent describing the wavelength dependence of optical backscatter between two wavelengths. Where previous interpretation of Ångström exponent was that of a particle size indicator, the use of light polarization makes it possible to investigate the Ångström exponent dependence on the particle shape by separately retrieving the backscattering Ångström exponent of the spherical (s) and non-spherical (ns) particles contained in an atmospheric particle mixture $(p) = \{s, {\rm ns}\}$(p)={s,ns}. As an output, analytical solutions of the Maxwell's equations (Lorenz-Mie theory, spheroidal model) can then be applied to investigate the Ångström exponent dependence on the particle size and complex refractive index for each assigned shape. Interestingly, lidar-retrieved vertical profiles of backscattering Ångström exponents specific to $s$s- and ns-particles can be used by the optical community to evaluate a range of involved particle sizes and complex refractive indices for both particle shapes, $s$s and ns, as we remotely demonstrate on a case study dedicated to a dust nucleation event.

中文翻译：

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关于使用光偏振来研究反向散射Ångström指数的大小，形状和折射率依赖性。

在这封信中，我们利用光的偏振特性来研究描述两个波长之间光学反向散射的波长依赖性的Ångström指数。在以前对Ångström指数的解释是粒度指示剂的解释中，使用光偏振可以通过分别获取球形和非球形（）的反向散射Ångström指数来研究Ångström指数对颗粒形状的依赖性。 ns）个包含在大气粒子混合物$（p）= \ {s，{\ rm ns} \} $（p）= {s，ns}中的粒子。作为输出，可以将麦克斯韦方程组的解析解（洛伦茨-米氏理论，球体模型）应用于研究每种分配形状的Ångström指数对颗粒尺寸和复折射率的依赖性。有趣的是