Stacked geometry concept for CosmicWatch based muon detectors in coincidence mode

Douglas Jackson; Ishannita Banerjee; John Naber; Swagato Banerjee

arxiv: 2601.10879 · v2 · submitted 2026-01-15 · ⚛️ physics.ins-det

Stacked geometry concept for CosmicWatch based muon detectors in coincidence mode

Ishannita Banerjee , Swagato Banerjee , Douglas Jackson , John Naber This is my paper

Pith reviewed 2026-05-16 13:11 UTC · model grok-4.3

classification ⚛️ physics.ins-det

keywords cosmic muonsscintillator detectorscoincidence detectionbackground reductionstacked geometrySiPM sensorsArduino acquisitionflux monitoring

0 comments

The pith

Stacked scintillator detectors run in coincidence to cut uncorrelated background in cosmic muon measurements.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper describes two CosmicWatch muon detector modules stacked and wrapped together, each read by its own SiPM and linked through Arduino microcontrollers so that only events producing signals in both layers within a short time window are recorded. This geometry restricts the accepted solid angle to particles that cross both scintillators and the coincidence requirement discards random hits from noise or single-layer background. The resulting count rates therefore contain a higher fraction of true cosmic muons. The instrument was operated through the 2024 total solar eclipse and maintained stable performance under field conditions. The architecture is presented as inexpensive and scalable enough for building distributed arrays that monitor muon flux over large areas.

Core claim

A stacked pair of scintillator modules operated in coincidence defines a constrained solid angle and applies a temporal filter that rejects uncorrelated background events and local electronic noise while preserving the large majority of true muons that traverse both layers.

What carries the argument

The stacked scintillator geometry that limits acceptance angle together with coincidence logic on linked Arduino microcontrollers.

If this is right

Cleaner count rates become available for tracking variations in cosmic muon flux.
Local electronic noise contributes far less to the recorded data.
Portable, battery-powered units can be replicated to form geographically distributed monitoring networks.
Field deployment remains practical, as shown by continuous operation through a total solar eclipse.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

The same stacking principle could be combined with pulse-height analysis to separate muons from other penetrating particles.
Citizen-science arrays built from these units might map regional differences in atmospheric muon production linked to weather or solar activity.
If the coincidence window is made adjustable, the design could test how background rejection trades off against muon acceptance in different environments.

Load-bearing premise

The chosen coincidence time window and layer spacing reject most uncorrelated background while still capturing essentially all genuine muons that cross both detectors.

What would settle it

A direct comparison of single-layer versus coincidence count rates during a period of known stable muon flux; if the coincidence rate falls far below the expected true-muon rate, the assumption that genuine events are preserved would be falsified.

read the original abstract

CosmicWatch-based muon detectors are inexpensive, handheld, battery-powered, portable instruments designed to measure the flux of secondary muons produced when primary cosmic rays continuously strike the Earth's atmosphere. As these muons pass through the detector, plastic scintillators generate light, which is collected by silicon photomultiplier (SiPM) sensors and converted to an electric signal. The signal is processed by an Arduino-based acquisition system and recorded as count rates corresponding to the cosmic muon flux. A stacked configuration consisting of two scintillator modules wrapped together and read by two SiPM sensors, which are operated in coincidence mode via linked Arduino microcontrollers, is presented. The novelty of this work is in demonstrating that detector geometry improves signal purity by defining a constrained solid angle and enabling coincidence filtering, thereby reducing uncorrelated background and local electronic noise. The system was deployed during the 2024 total solar eclipse, demonstrating stable field operation and reliable flux monitoring. The mechanical design, coincidence logic implementation, and performance characterization of the instrument are described. Overall, this work demonstrates a scalable, robust, and inexpensive architecture suitable for geographically distributed muon flux monitoring arrays.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Desk Editor's Note private letter to a colleague

The paper gives a clear build for stacking two CosmicWatch modules with Arduino coincidence logic and shows it running stably during the eclipse, but it never measures the background rejection or purity gain it claims.

read the letter

The main point is a hardware refinement: two scintillator-SiPM units stacked together and read out in coincidence through linked Arduinos to narrow the solid angle and cut uncorrelated hits. They describe the wrapping, the mechanical stack, the coincidence window logic, and a field run during the 2024 eclipse that produced steady count rates. That part is useful and reproducible for anyone who already uses CosmicWatch boards and wants a quick way to add coincidence without new electronics. The design choices are straightforward and the field test confirms the setup survives real conditions. The soft spot is the missing data. The text asserts that the geometry plus coincidence reduces background and electronic noise, yet it only reports raw rates and stability notes. There is no single-versus-coincidence rate comparison, no accidental-coincidence probability, and no efficiency or purity number. Without those, the central claim stays an untested design choice rather than a demonstrated result. This is for groups building small, low-cost muon arrays or running student projects. A reader who needs the mechanical details and Arduino code pattern will get something concrete. The work is honest engineering rather than overstated physics, so it deserves a serious referee who can ask for the rate comparisons and a short efficiency calculation. I would send it to review with that request rather than desk-reject it.

Referee Report

2 major / 2 minor

Summary. The manuscript presents a stacked geometry for CosmicWatch muon detectors consisting of two scintillator modules read by separate SiPMs and operated in coincidence via linked Arduino microcontrollers. It claims that the constrained solid angle and coincidence filtering reduce uncorrelated background and electronic noise, thereby improving signal purity relative to single-detector operation. The work describes the mechanical stacking, coincidence logic implementation, and reports raw count rates plus stability notes from a deployment during the 2024 total solar eclipse, concluding that the architecture is scalable and suitable for distributed flux-monitoring arrays.

Significance. If quantitative validation of the purity gain is supplied, the design offers a low-cost, portable hardware modification to an existing open-source detector that could enable geographically distributed coincidence arrays for cosmic-ray studies. The eclipse deployment demonstrates field robustness, but the absence of comparative metrics leaves the claimed improvement as an unverified design assumption rather than a demonstrated result.

major comments (2)

[Performance characterization] Performance characterization section: only raw count rates and qualitative stability notes are reported; no single-detector versus coincidence rate comparison, no measured or calculated accidental-coincidence probability, and no efficiency or purity figure of merit are provided. These data are required to substantiate the central claim that the stacked geometry plus coincidence window rejects uncorrelated background while retaining essentially all true through-going muons.
[Abstract and §1] Abstract and §1: the stated novelty is that detector geometry 'improves signal purity' via coincidence filtering, yet the manuscript supplies no quantitative evidence (e.g., background rejection factor or purity ratio) to support this assertion over a single-detector baseline.

minor comments (2)

[Coincidence logic implementation] The coincidence-window timing parameters and Arduino logic diagram would benefit from explicit numerical values and a timing diagram to allow replication.
[Figures] Figure captions should explicitly state whether the plotted rates are single-detector or coincidence-mode data.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive review. We agree that quantitative comparisons are needed to substantiate the purity improvement and will add the requested metrics and calculations to the revised manuscript while clarifying the scope of the novelty claim.

read point-by-point responses

Referee: [Performance characterization] Performance characterization section: only raw count rates and qualitative stability notes are reported; no single-detector versus coincidence rate comparison, no measured or calculated accidental-coincidence probability, and no efficiency or purity figure of merit are provided. These data are required to substantiate the central claim that the stacked geometry plus coincidence window rejects uncorrelated background while retaining essentially all true through-going muons.

Authors: We acknowledge that the current draft reports only raw rates and stability notes without direct comparisons. In revision we will add: (i) count-rate data acquired in both single-detector and coincidence modes under identical conditions; (ii) explicit calculation of accidental-coincidence probability using the observed singles rates and the measured coincidence window width; (iii) geometric efficiency estimates together with a purity figure of merit defined as the fraction of coincidence events attributable to through-going muons. These additions will directly address the central claim. revision: yes
Referee: [Abstract and §1] Abstract and §1: the stated novelty is that detector geometry 'improves signal purity' via coincidence filtering, yet the manuscript supplies no quantitative evidence (e.g., background rejection factor or purity ratio) to support this assertion over a single-detector baseline.

Authors: We will revise the abstract and Section 1 to state that the novelty consists in the practical stacked-coincidence implementation for CosmicWatch detectors, with the purity gain arising from the constrained acceptance and coincidence logic. The quantitative background-rejection factor and purity ratio will be supplied in the expanded performance section, allowing the abstract to reference the measured improvement. revision: yes

Circularity Check

0 steps flagged

No circularity: purely descriptive hardware and deployment report

full rationale

The paper presents a mechanical stacking design, Arduino-based coincidence logic, and field deployment notes for CosmicWatch muon detectors. No mathematical derivations, equations, fitted parameters, or predictions appear in the abstract or described content. The central claim of improved signal purity via geometry and coincidence is framed as a design feature demonstrated through stable operation, without any reduction to self-citations, ansatzes, or input data by construction. This matches the reader's assessment of a score of 1.0 with no derivation chain present.

Axiom & Free-Parameter Ledger

0 free parameters · 2 axioms · 0 invented entities

The paper relies on standard scintillation and coincidence principles without introducing new free parameters, axioms, or postulated entities.

axioms (2)

standard math Standard scintillation light collection and SiPM signal processing apply to the stacked modules.
Invoked implicitly when describing light generation and signal conversion.
domain assumption Coincidence logic on linked Arduinos can be implemented with negligible dead time for muon rates.
Assumed when claiming stable field operation.

pith-pipeline@v0.9.0 · 5500 in / 1140 out tokens · 54628 ms · 2026-05-16T13:11:42.228379+00:00 · methodology

discussion (0)

Lean theorems connected to this paper

Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

IndisputableMonolith/Foundation/RealityFromDistinction.lean reality_from_one_distinction unclear

?

unclear
Relation between the paper passage and the cited Recognition theorem.

stacked configuration... coincidence mode via linked Arduino microcontrollers... constrained solid angle and enabling coincidence filtering

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