# Re: Mean Energy

From: G. Battistoni <giuseppe.battistoni_at_mi.infn.it>
Date: Fri, 23 Apr 2010 23:24:14 +0200

Hi
That plot was obtained by plotting the content of a file called **tab.lis
corresponding to the dector associated to your USRBDX. That file
contains a table of values organized
in 4 columns. The table starts from the lowest energy and the four
columns represent respectively
E_min, E_max, the differential fluence F and the statistical error in
percentage Sigma_F
You can obtain the average energy by processing those numbers in the
following way:
For each energy bin you build the product of mean energy of the bin E
times F
and sum together all the results, obtaining S1.
In parallel, you also build the sum of all F values, obtaining S2.
Then the average energy is <E> = S1/S2

In case of a linear energy binning the mean energy of bin i is
(E_max(i)+E_min(i))/2.
For a log energy binning a better evalutation of the mean energy of the
bin is the
square root of the product E_max(i) times E_min(i).

Giuseppe Battistoni

Emre EROGLU wrote:
> Hi all,
>
> I have positron energy distribution with USRBDX card (see attachment).
> I need to know or calculate mean positron energy. How can i do?
>