An attempt to detect Cosmic Rays

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An attempt to detect Cosmic Rays coming into our
atmosphere with the help of some
statistics   By   Rodney Howe, MS. GIS/Remote
Sensing 07.02.2002
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Menzel 3 in the constellation Norma might be a
source for Cosmic Rays in our galaxy
High energy protons produced in these outbursts
get trapped in the galactic magnetic field
and might make there way into our atmosphere
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Cosmic Rays greater than the Greisen-Zatsepin-Kuzm
in (GZK) limit, eV gt 5x 1017, may come from
other galaxies.
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Protons that collide with the atmospheric
molecules at very high energies, around the GZK
limit, electron volts gt e19
Cosmic Ray
pions, muons
Create a shower or cascade of pions that decay
into muons (high energy electrons) which might be
detected by two separate Geiger counters.
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Pierre Augers Experiment (1938) with Geiger
Counters on the ground

• explore the following null hypothesis.
• That simultaneous clicks, with two or more
  detectors spaced a good distance apart (5 - 10
  meters), are not coincidental random clicks, but
  are actual Cosmic Ray Showers from high energy,
  around the GZK limit, protons impinging on our
  atmosphere.

• explore the alternative hypothesis.
• That data do not support that cosmic ray
  detection is more likely than coincident clicks
  due to chance, i.e. there might be a chance that
  coincidental (simultaneous) clicks do not come
  from cosmic rays created in a cascade shower high
  in our atmosphere.

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Two Geiger counters and a laptop to record
coincident clicks.
Recording software used NASAs Radio Jove,
January 2000.
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Geiger Counter A instructions come from John
Iovine's 'Electronic Projects for the 21st
Century'.
The Geiger-Muller tubes on both counters are the
same, but the electronics of the detectors is
slightly different.
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Geiger Counter B instructions from Images
Company at http//www.imagesco.com
Counter B, has less voltage output at the
earphones than Counter A
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Radio Jove software records data from the
laptops sound card. Counter A and B record at
different decibels on the Y axis.
Counter A averages around 3, counter B around 2
decibels. Coincident clicks are additive and go
as high as 4 decibels.
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We can use spread sheet functions to display
daily acquired data Joseph DiVerdi
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Then, create histograms of average daily
coincident hits. (Joseph DiVerdi)
There is some variation from hour to hour, day to
day, but is this different than just the random
background coincidence?
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And finally, total aggregate coincident hits per
hour. (Joseph DiVerdi)
This gives a nice Poisson distribution, it is a
distribution of hourly hits. But can we
determine if these are cosmic ray shower events?
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The data may tell us more if we could identify
clusters, that are different from a set of
randomized clusters.
For example we might identify the cluster sizes
of counter A counter B, and the additive
coincident hits of A B.
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We basically have a "trimodal" distribution in
this data. And we are going to want to
calculate three thresholds.

• The first will be a height that will separate
  events from counter A compared to counter B.
• The second will be a height that will distinguish
  events from counter B compared to counter AB.
  (potential cosmic ray shower)
• The third threshold will be to separate out
  samples with no spike and counter A.

One way to identify these three clusters is to
percolate data from the recorded data and let
the clusters fall into one of three categories,
then compare this with a randomly generated set
of clusters.
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Some Random
Clustering Statistics AVE ADEV
SDEV VAR SKEW
CURT 4.97 2.49 2.88
8.28 .00 -1.19 ns 2744
1639 1021 601 373 226 148 73
48 25 10 3 0 0 0 0
0 0 .47000 500 17665 2512
213.2387 .4810 8.5173930000 .10
.4820 8.5812940000 .10 ns 2387 1443
839 504 291 178 95 45 40 23
10 7 2 0 0 0 0 0
.48200 500 16933 5331
490.4283 .4910 8.8366640000 .10 .4920
8.1906320000 .10 .4930 9.2464790000 .10 .4940
8.1969880000 .10 Software from a book by
Stauffer and Amnon, 1992, 'Introduction to
Percolation Theory'.
note the skew is 0, indicating clusters are
random.
note the skew is 0, which indicates the
clusters are random.
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Plotting the output from the percolation routine
using random values from the computer.
Log of random cluster sizes on the Y axis,
Percolation value p on the X axis.
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Read from rajove.log rows 32800 Please
wait... Load R array from temp.log rows
32433 Some Geiger Counter
Clustering Statistics AVE ADEV
SDEV VAR SKEW
CURT 2.50 1.11 2.02
4.09 2.36 6.51 .3810
8.7795570000 .10 .3820 8.2940490000 .10 ns
0 0 0 0 0 0 0
0 33 22 27 11 1 0 0
0 0 0 .38200 500 94
6500 804.0000 .3910 8.2940490000
.10 .3920 8.7795570000 .10 .3930 8.2940490000
.10 ns 0 0 0 0 0
0 0 0 31 23 27 11 1
0 0 0 0 0 .39300 500
93 6500 841.0000
note the skew is 2.36, and the Kurtosis is 6.51
which indicates the clusters are not random.
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Plotting the output from the percolation routine
we can identify three clusters, plus perhaps a
fourth.
The third cluster will be coincident background
noise, but it is difficult to say which of these
events are cosmic ray showers.
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If we map the data in 2D E space using a Blue
Red Yellow pallet we can compare random data
to recorded cluster data.
This is random background data.
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This is clustered from an hour of Radio Jove
data. It does not seem possible to determine
cosmic ray events with this equipment.
Perhaps more sensitive equipment, and longer
exposure times?
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In Memory of Art Stokes