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Examining cosmic ray neutron radiation near ground by neutron monitors for example (http://www.nmdb.eu), different stations show similar dynamics in the signal.

At one station, I like to "substract" the incoming radiation in order to obtain information about local effects. Can I take the incoming signal from another station? But signals of two stations differ:

  1. sometimes lags up to 10 days between similar peaks
  2. peaks differ in amplitude
  3. efficiencies differ between the detectors

How to correct for such effects analytically? (like the known corrections for pressure, latitude, altitude, etc.) Or are there appropriate techniques for statistical decomposition?

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I'm a bit confused. If station A's signal looks like station B's but lagging by 10 days, that must be a coincidence. The time travel delay between different parts of the planet is measured in milliseconds, not days. Or are you just trying to use one station's peaks as templates for a "generic peak" that can be subtracted elsewhere? –  Chris White Feb 5 at 21:47
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I have to agree with @Chris at this point. How comfortable are you with the application of counting statistics to rate measurements? Do you know what I mean if I say something like "well, the bump looks good, but it is only about 2.4 sigma above background" and what that does not imply? Do you know how to do a calculation to get that figure? –  dmckee Feb 6 at 0:07
    
Of course I only mean signifikant peaks below 1 sigma, so real world dynamics. Once I saw quite similar peaks in a 10 days distance, but maybe it really was coincidence. So let us forget about point 1, and focus on 2 and 3, please. –  Martin Feb 6 at 8:12
    
Larger numbers of standard deviations (sigma) above background makes a peak more significant. A one-sigma peak is something that can occur by pure chance (i.e. not indicating anything interesting but just coincidence) very often. The definition of "significant" depends a bit of your field, the number of bins you examine and the size of your data set, but you really need at least three sigma to feel really confident. –  dmckee Feb 8 at 0:41
    
This is not a question about noise, it is about comparing dynamics, non-noise peaks (that happen for both detectors but differ in amplitude), trends of two signals different in mean, amplitude, number of channels, effectiveness for specific energies. In the comment above I meant "above" instead of "below" but wasnt able to edit after 5mins. –  Martin Feb 8 at 6:41

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