Study of Muon Content in Air Showers Using the CONEX 3D Simulation Framework and a Simplified Core-Corona Model

Core Concepts

The CONEX 3D simulation framework, integrated with CORSIKA, provides an efficient way to study muon content in air showers and assess the impact of the core-corona model on muon production, potentially addressing the muon puzzle in ultra-high energy cosmic ray physics.

Abstract

• Bibliographic Information: Botti, A.M., Goos, I.A., Perlin, M., & Pierog, T. (2024). Study of the muon component in the core-corona model using CONEX 3D. Journal of Cosmology and Astroparticle Physics. arXiv:2411.06918v1 [astro-ph.HE]

• Research Objective: This paper investigates the muon content in air showers generated by ultra-high energy cosmic rays using the CONEX 3D simulation framework and explores the impact of a simplified core-corona model on muon production.

• Methodology: The study utilizes the CONEX 3D simulation framework, integrated with CORSIKA, to simulate air showers and analyze muon-related observables. The researchers compare CONEX 3D simulations to CORSIKA simulations and experimental data from KASCADE, IceTop, and the Pierre Auger Observatory. They implement a simplified core-corona model in CONEX to assess its effect on muon content.

• Key Findings: CONEX 3D accurately reproduces muon-related air shower observables compared to CORSIKA and experimental data. The simplified core-corona model, incorporating statistical hadronization in the dense interaction region (core) and string fragmentation in the less dense region (corona), leads to a 15% to 20% increase in muon content at a primary energy of 10^19 eV.

• Main Conclusions: The CONEX 3D framework offers an efficient and accurate tool for simulating air showers and studying muon content. The findings suggest that the core-corona model, by influencing the energy distribution between electromagnetic particles and hadrons, can potentially explain the observed muon excess in air shower data, contributing to the resolution of the muon puzzle.

• Significance: This research advances the understanding of muon production mechanisms in high-energy cosmic ray interactions and highlights the potential of the core-corona model in explaining experimental observations. The improved efficiency of CONEX 3D facilitates more extensive and detailed air shower simulations, enabling further exploration of the muon puzzle and cosmic ray physics.

• Limitations and Future Research: The study employs a simplified version of the core-corona model, neglecting potential nuclear effects and assuming uniform application across pseudorapidities. Future research could incorporate more realistic implementations of the core-corona model, considering nuclear effects and variations with pseudorapidity. Further investigation into the energy dependence of the core fraction and its impact on muon production is also warranted.

Stats

At a primary energy of E0 = 10^19 eV, the core-corona model leads to an increase of 15% to 20% in the muon content.
The muon energy threshold in KASCADE is based on the minimum energy required to penetrate the detector shield (230 MeV).
For Auger and IceTop, the muon energy threshold was determined by considering their energy distributions and experiment altitudes, ensuring it is sufficiently low to capture most particles (200 MeV and 300 MeV, respectively).
The simulation library for Auger comprises 90 mean proton air showers, while IceTop’s and KASCADE’s have 240.
For each set of simulations, five different zenith angles were simulated with the same weight (sin θ): 0◦, 27◦, 41◦, 53◦and 67◦.
The study analyzed distance ranges of d = 1000 −1100 m for Auger, d = 400 −500 m for IceTop, and d = 100 −200 m for KASCADE.

Quotes

"Currently, the discrepancy between the muon density measured with surface arrays and that predicted by hadronic interaction models [4] represents one of the most pressing questions in air shower physics."
"To shed light on the muon puzzle, improving the air shower simulation frameworks and enhancing their technical capabilities to integrate new theoretical models is of utmost importance."
"Recent measurements at the LHC hint towards the existence of other production mechanisms, such as collective statistical hadronization. This mechanism leads to an increase in the muon production in hadronic cosmic ray interactions [14, 30–32]."

Key Insights Distilled From

Study of the muon component in the core-corona model using CONEX 3D

by Ana Martina ... at arxiv.org 11-12-2024

https://arxiv.org/pdf/2411.06918.pdf

Deeper Inquiries

How might advancements in quantum computing impact the efficiency and accuracy of air shower simulations like those performed with CONEX 3D?

Advancements in quantum computing hold the potential to revolutionize air shower simulations like those performed with CONEX 3D in several ways:
Efficiency:

Speeding up Monte Carlo simulations: Quantum algorithms, such as quantum Monte Carlo, can potentially offer significant speedups for the Monte Carlo simulations at the heart of air shower modeling. This enhanced efficiency could allow for the simulation of a significantly larger number of showers, leading to improved statistical accuracy and a better understanding of rare events.
Accelerated optimization: Quantum computers excel at solving optimization problems. In the context of CONEX 3D, this capability could be harnessed to optimize the parameters of the simulation, such as the energy thresholds for transitioning between Monte Carlo and cascade equations, leading to faster and more computationally efficient simulations.
Accuracy:

More realistic particle interactions: Quantum computers could enable the simulation of particle interactions at a more fundamental level, potentially incorporating quantum chromodynamics (QCD) effects more accurately than is currently possible with classical computing methods. This enhanced realism could lead to more precise predictions of particle production and shower development.
Improved modeling of complex phenomena: Quantum simulations might be able to capture complex phenomena that are challenging to model classically, such as the formation and evolution of the quark-gluon plasma in high-energy collisions. This capability could lead to a more complete and accurate understanding of the hadronic interactions that drive muon production in air showers.
Challenges and Outlook:
While the potential benefits are significant, several challenges need to be addressed before quantum computing can be effectively applied to air shower simulations:

Scalability: Building and operating large-scale, fault-tolerant quantum computers remains a significant technological hurdle.
Algorithm development: Designing quantum algorithms specifically tailored for the complexities of air shower simulations is an active area of research.
Integration with existing frameworks: Integrating quantum algorithms into existing air shower simulation frameworks like CONEX 3D will require significant software engineering efforts.
Despite these challenges, the rapid progress in quantum computing hardware and software suggests that this technology could play a transformative role in advancing our understanding of air showers and cosmic rays in the future.

Could alternative explanations, beyond the core-corona model, account for the observed muon excess in air shower data, and if so, what are their potential implications?

Yes, several alternative explanations, beyond the core-corona model, could potentially account for the observed muon excess in air shower data. Here are a few possibilities:
1. Uncertainties in Hadronic Interaction Models:

Incomplete understanding of high-energy interactions: Our current understanding of hadronic interactions at ultra-high energies, primarily extrapolated from lower-energy collider data, might be incomplete. There could be unknown particle production mechanisms or resonance states that enhance muon production in air showers.
Limitations of string fragmentation models: While string fragmentation models have been successful in describing many aspects of particle production, they might not fully capture the complexities of hadronization at the highest energies. Alternative models, such as those incorporating color reconnection effects or other QCD-inspired approaches, could lead to different muon yields.
2. Cosmic Ray Composition and Energy Spectrum:

Heavier primary composition: A higher fraction of heavy nuclei (e.g., iron) in the cosmic ray flux at ultra-high energies could contribute to the muon excess. Heavier nuclei produce more muons per shower compared to protons.
Steeper energy spectrum: A steeper-than-expected cosmic ray energy spectrum could also lead to an apparent muon excess. If the spectrum falls off more rapidly with energy, the observed muon number would be higher than predicted based on a shallower spectrum.
3. New Physics Beyond the Standard Model:

Exotic particle decays: The decay of hypothetical particles beyond the Standard Model, produced in the initial cosmic ray interaction, could contribute to the muon flux in air showers. Examples include supersymmetric particles or dark matter candidates.
Lorentz invariance violation: Some theories propose that Lorentz invariance, a fundamental symmetry of spacetime, might be violated at ultra-high energies. Such violations could affect particle interactions and potentially enhance muon production.
Implications:
The confirmation of any of these alternative explanations would have profound implications for our understanding of:

Particle physics: It could point towards new physics beyond the Standard Model, requiring modifications to our current theoretical frameworks.
Astroparticle physics: It would impact our understanding of the origin, acceleration, and propagation of cosmic rays.
Cosmology: It could provide insights into the nature of dark matter and the evolution of the early universe.
Further experimental and theoretical investigations are crucial to disentangle these possibilities and determine the true origin of the muon excess.

If the muon puzzle is definitively solved, what new avenues of research in astroparticle physics might open up, and how could these advancements impact our understanding of the universe?

Solving the muon puzzle would be a major breakthrough in astroparticle physics, with the potential to unlock exciting new avenues of research and deepen our understanding of the universe:
1. Precision Cosmic Ray Physics:

Accurate composition measurements: With a reliable model for muon production, we could significantly improve our ability to determine the composition of cosmic rays at ultra-high energies. This would allow us to pinpoint the sources of these particles and understand the acceleration mechanisms that power them.
Probing cosmic magnetic fields: The deflection of charged cosmic rays in magnetic fields depends on their mass and energy. By accurately modeling muon production, we could use cosmic ray observations to map out the structure and strength of magnetic fields in our galaxy and beyond.
2. Hadronic Interaction Physics at Extreme Energies:

Testing and refining interaction models: Solving the muon puzzle would provide crucial feedback for improving hadronic interaction models at energies far beyond the reach of current colliders. This would enhance our understanding of fundamental particle physics and the behavior of matter under extreme conditions.
Searching for new physics: The solution to the muon puzzle might involve new physics beyond the Standard Model. This could motivate searches for exotic particles or phenomena in both cosmic ray experiments and collider experiments like the LHC.
3. Unveiling the Secrets of Cosmic Accelerators:

Understanding the origin of ultra-high energy cosmic rays: By precisely measuring the composition and energy spectrum of cosmic rays, we could identify the astrophysical objects responsible for accelerating these particles to such extreme energies. Candidates include supernova remnants, active galactic nuclei, and gamma-ray bursts.
Probing the nature of extreme environments: The study of cosmic rays provides a unique window into the most energetic processes in the universe. Solving the muon puzzle would enhance our ability to study these extreme environments and the physics that governs them.
4. Multi-Messenger Astronomy:

Combining cosmic rays with other messengers: With a better understanding of cosmic ray interactions, we could more effectively combine cosmic ray observations with data from other messengers, such as neutrinos, gamma rays, and gravitational waves. This multi-messenger approach promises a more complete and insightful view of the cosmos.
Impact on Our Understanding of the Universe:
Solving the muon puzzle would have far-reaching implications for our understanding of:

The origin and evolution of cosmic rays: We could trace the journey of cosmic rays back to their sources and understand how they are accelerated to such incredible energies.
The nature and distribution of matter and magnetic fields in the universe: Cosmic rays act as probes of the interstellar and intergalactic medium, providing information about the composition, density, and magnetic fields in these regions.
Fundamental physics: The solution might involve new particles or forces beyond the Standard Model, revolutionizing our understanding of the building blocks of nature.
In conclusion, solving the muon puzzle would not only resolve a long-standing mystery in astroparticle physics but also open up new frontiers of research, leading to a deeper and more comprehensive understanding of the universe and its fundamental constituents.