(meteorobs) the population indices

[RainerArlt]

Hello Sahar and all,

> [...]
> This equation delivers a set of corresponding <Delta m>. Using Table, 
> we converted <Delta m> into population indices (this will give us the 
> r-values for our main effective observing periods.).
> r	<Delta m>	r	<Delta m>
> 1.5	5.830	3.1	2.750
> 1.6	5.301	3.2	2.682
> 1.7	4.894	3.3	2.618
> 1.8	4.568	3.4	2.559
> 1.9	4.298	3.5	2.503
> 2.0	4.069	3.6	2.450
> 2.1	3.872	3.7	2.400
> 2.2	3.700	3.8	2.353
> 2.3	3.549	3.9	2.308
> 2.4	3.413	4.0	2.266
> 2.5	3.291	4.1	2.226
> 2.6	3.180	4.2	2.187
> 2.7	3.079	4.3	2.151
> 2.8	2.987	4.4	2.116
> 2.9	2.902	4.5	2.082
> 3.0	2.823		
> 
> But we wants to know where this table come from and how can we 
> account them. Can you tell us about it?

The conversion table is obtained by computer simulations. One does
the opposite way of determining the population index: one assumes
a population index. So the true distribution of meteors over
magnitudes is known (exponential). You generate random numbers
with this distribution. You also have to know the perception
probabilities of a meteor at a given distance from the limiting
magnitude. These are taken from Koschack & Rendtel
(http://www.imo.net/articles/results.html), which has recently
been reviewed by Pete Gural an WGN. You have to convolve the
meteors generated also with this distribution. After generating
a million meteors, you get a distribution as if it would have
been observed. You compute the average Delta-m and get the
value in the second column of the Table.

Best wishes,
Rainer