function [y]=N_sphere(d);
%
% 2005.12
% Emmanuel Boss
% emmanuel.boss@maine.edu
% School of Marine Sciences, University of Maine, USA
%
% Calculates the non-normalized PSD of the calibration beads.
%
%
% INPUT
% Sphere diameter                               (D)     [m] 

% OUTPUT
% concentration of particle of size D            (y)

%modal particle diameter
mean=1.992e-6;
%standard deviation oaround particle diameter
sd=0.025e-6;

y=exp(-(d-mean).^2./(2*sd^2));
