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Muon Project

Aware Coincidence Box Decoder (C-Box): $85
Aware Triple Coincidence Box Decoder (Triple C-Box) $129
Phone or write to order or for more details.
Aware Coincidence Box
To: Bryan J. Boardman, Aware Electronics Corp.:

I have been a contributor to your company's website from St. Croix, Virgin Islands. After teaching science at St. Joseph High School for 29 years and all schools for 55 years, I have retired at the age of 80 and moved to St. Francis de Sales High School in Toledo, Ohio. But I have not retired from my many interests which include monitoring the variations in the muon flux. Using my equipment from Aware, I recently monitored the muon flux intensity variations for one day from 8/20/17 to 8/21/17 which included the partial solar eclipse in this area. The results show an interesting low point around the time the partial solar eclipse was at a maximum. The online article on my website is at Solar Eclipse Muon Data or from the link at the top of Monitoring Muons on the Surface of the Earth

In Toledo, Ohio, two RM-60 geiger counters were placed in an horizontal position, connected to a coincidence detector, and the data was recorded with a LCD -90 Pro Micro-Controller Data- Logger for a 25 hour and 24 minutes time period from 2023 EDT on 08/20/17 to 2147 EDT on 08/21/17. (The equipment names and models refer to the products from the Aware Electronics Company.)

Using a computer, a graph was made of the data showing the muon flux level vs time. The muon flux counts were grouped into 120 minute periods on this graph. A regression analysis was also performed which is shown by the slopping line on the graph.

Eclipse Muon Flux - Toledo Ohio

To: Bryan J. Boardman, Aware Electronics Corp.:

Two RM-60s and a C-Box
I just posted graphs of 1) A week-long muon observation in the normal up-down coincidence detector position and 2) Around day-long muon observations of the coincidence detector placed in NS, EW positions and 45 deg, angles facing N,E,W, and S.

The week-long graph shows a slight downturn in the regression line. Perhaps it is connected with the passing of a sunspot at the start of the week. The variations in the coincidence detector positions clearly shows different average muon counts with the EW and NS positions the lowest and the 45 deg angle positions slightly higher but lower than the up-down position. The new data is posted (together with the previous data) at:
Monitoring Muons on the Surface of the Earth

Viewers are welcome to analyze and relate the data to astronomical changes and send feedback to the email address listed on my website.

James Petrait
St. Croix, U.S.Virgin Islands

Be sure to check out James's great Muon website by-way-of the link above.

Ron Fleshman's Cosmic Rays page uses two RM-60s, an Aware Coincidence Box, a telephone line splitter and two copies of Aw-Radw software to record both cosmic ray hits and background radiation levels:
Ron Fleshman's Cosmic Rays
Pisgah Astronomical Research Institute's Cosmic Ray Monitor uses two RM-70s and an Aware Coincidence Box:
Pisgah Astronomical Research Institute's Cosmic Ray Monitor
Cosmic ray info.:
Terrestrial cosmic ray intensities

We now sell a triple coincidence box (Triple C-Box $129) for use with three RMs to plot Electromagnetic cascades in lead for generation of Rossi Curve.

Rossi Curve Info.:
Wikipedia Rossi curve
Demonstrating cosmic ray induced electromagnetic cascades

Bruno Rossi info.:

Reproducing Rossi's cascade experiment using three RM-80s, one Triple C-Box or two C-Boxes, one USB-MSP or LCD-90 Pro, and Aware software or your own interface software

Also needed lead or iron absorber sheets, 6 x 6 to 12 x 12 or larger, various thicknesses. Suitable lead absorbers can be made from lead flashing used in the building industry. McMaster Carr sells lead sheets McMaster Carr Lead Sheets

Also needed spacers to hold the pile of lead sheets ~2.5cm above the RM-80 windows.

Place three RM-80s on a table, on their backs, with the windows facing up. Position them in a triangle formation such that the windows are as close as possible to each other.

Place the spacers around the R-80s then place the lead sheets on top of the spacers. Size the spacers to provide an ~2 to 3cm gap between the top of the RM-80 windows and the bottom of the lead sheets.

Plug the three RM-80s into the Triple C-Box and plug the Triple C-Box into the USB-MSP or LCD-90. Start recording the coincidences per hour. Every hour or more, add an additional absorber sheet to the pile. Plot the coincidences per hour versus total thickness. It should generate a graph similar to the following:

Shower curve obtained by Rossi using a triangular arrangement of GM tubes
Coincidence Experiments using two RM-60s:


"We propose to explore the nature of cosmic particles by proposing an astute combination of measurements made in spatially distinct points by several Geiger counters. The analysis of the signals acquired by these detectors, and in particular the quasi-simultaneous measurement of the passage of ionizing particles by several detectors, makes it possible to supplement the information on the dose rate with information about the direction of incidence of the particle. We thus reproduce a number of experiments, according to a so-called coincidence strategy, which made it possible more than 70 years ago to elucidate the nature of the cosmic particles.

Two RM-60s fixed on an equatorial plank

Experimental implementation of the coincidence method by means of two Geiger counters fixed on an assembly (equatorial plank) allowing to vary the zenith angle. Top right: output voltage of each Geiger counter, illustrating the events observed in coincidence (pulse in the middle of the screen) and the rejection of the signals observed by a single detector (pulses on the bottom trace, right half of the 'screen).
Two RM-60s and lead

Experimental set-up: The two Geiger counters are in a configuration in which they have little probability of detecting an incident cosmic ray and only the sheaves of particles induced by interaction with the lead sheets can induce a simultaneous response of the two detectors. The lead sheets are 2 mm thick and a number ranging from 0 to 10 sheets are placed on the counters. All the leaves are cut out according to a square of 5x5 cm2.
Two RM-60s and lead
Interpretation of the measure. The "two-count" configuration of the two counters has only a small probability of detecting an incident particle (blue), and only the creation of a spray of secondary particles (red) reaching "both" Interpret the results of measurements.

Art and Muons. Aware's equipment used in Paris art exhibit NOX-MATTER:
NOX-MATTER A study for Muons and Silence
Another link about NOX-MATTER Study for Muons and Silence

Aware's C-Boxes each paired with two RM-60s utilized in NOX-MATTER:

An artist wiring NOX-MATTER:

Dear Sir,

Over a year ago, I purchased 2 RM-80's, a coincidence box decoder, plus software. I use my muon detector every day with an old 486 Dell that has run almost continuously since January 12, 2001.

My daily corrected muon counts show very good variability, and this variability allows me to study muon counts in relation to other data I am collecting about the Sun's behavior and the Earth's magnetic field.

My question has to do with neutrons. You offer equipment for detecting neutrons. I'm wondering whether that equipment could be used to detect the small variations in the background neutron count. I live at 43.15 North and 71.89 West, with an elevation of 630 feet and a cutoff rigidity of approximately 1.5 GV. The equipment would be kept in a room with a pretty constant temperature and snow would would not be allowed to accumulate on the roof.

Please let me know what you think and what equipment you believe I will need.

Dear John,

I think you might detect only one background neutron every few hours so it would be very hard to detect a pattern. The only additional information I would have is that which is on our website regarding the neutron tube.

From another page Page 2 which might help with muon pattern probability:
As mentioned elsewhere, Professor Jim C. Yu has written a lesson using the RM-60 and software in combination with a spreadsheet wherein students plot the frequency distribution of background radiation. This generates the classic bell shaped curve. Also calculated: Mean and standard deviation.
To view gif images of lesson generated by a scanner:

  • Click for Prof. Jim C. Yu's Lesson

    Example 3D Example 3D

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