Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Experimental and theoretical studies on visible light attenuation in
  water   In this study we describe lab experiments on determining the above water
reflectance Rrs coefficient, and the water attenuation coefficient Kd for fresh
water. Different types of screens (totally absorbent, gray, etc.) were
submerged in water (0-0.6 m) and illuminated from outside. The spectral density
of the water leaving radiance was measured for different depths. The results
were ran by a code which took into account the geometry of the incident
irradiation, the geometry of the screen under water, and boundary conditions at
the water surface provided by the radiation transfer theory. From the
experimental data and our model we obtain the spectral distribution of the
attenuation coefficient for fresh water and compared it with other data in
literature. These experiments, performed in the Nonlinear Wave Lab at ERAU#
represent just a preliminary calibration of the experimental protocol. More
tests with water of different degrees of turbidity, and possibly wave filed at
the water surface are in progress and will be presented in a forthcoming paper.

22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
7
The categories of this paper are: hep-th