Ultrahigh-energy cosmic rays (UHECRs) strike Earth with energies exceeding those achievable by any human-made particle accelerator by several orders of magnitude. Their extraordinarily high energies—often in the range of hundreds of exa-electron volts—raise profound questions about their sources and the mechanisms capable of accelerating particles to such extents. Traditionally, cosmic rays at these energies were assumed to be predominantly protons or light nuclei. However, new insights emerging from advanced computational simulations led by Penn State physicist Kohta Murase suggest that a significant fraction of these particles could instead be ultraheavy nuclei, atomic cores heavier than iron, traversing the depths of intergalactic space with surprising resilience.

Atomic nuclei, composed of tightly bound protons and neutrons, encapsulate nearly the entire mass of atoms while occupying only minuscule volumes within them. Most cosmic rays studied previously were assumed to be light nuclei primarily consisting of protons or helium nuclei. The new study challenges this view by demonstrating, through intricate modeling of particle interactions across cosmic distances, that nuclei with atomic mass exceeding that of iron may suffer less energy loss during their journey through the intergalactic medium compared to lighter counterparts. These ultraheavy nuclei, therefore, maintain their ultrahigh energies for longer distances, making them plausible candidates for detecting events like the Amaterasu particle on Earth.

One of the longstanding paradoxes in UHECR research has been the apparent mismatch between cosmic-ray trajectories and their inferred sources. The Amaterasu particle’s direction of arrival intriguingly pointed not towards a known cosmic accelerator but into a near-empty cosmic void. This inconsistency cast doubt on interpretations of cosmic-ray origins based on simpler models assuming only protons or light nuclei. Murase’s team posits that if these cosmic rays are heavier nuclei, their propagation pathways and magnetic deflection patterns would differ markedly, potentially reconciling observed arrival directions with realistic source scenarios.

The discovery that some ultrahigh-energy cosmic rays might be ultraheavy nuclei shifts the landscape of potential astrophysical accelerators. Violent cosmic environments capable of producing such nuclei include cataclysmic stellar deaths that culminate in black hole formation, highly magnetized neutron stars known as magnetars, and the colossal mergers of neutron star binaries. These extreme astrophysical events can unleash tremendous energy, sometimes manifesting as gamma-ray bursts — among the most luminous explosions ever recorded. The acceleration processes within these environments are thought to be capable of propelling atomic nuclei to energies exceeding 100 exa-electron volts, consistent with the energies of observed UHECRs.

The methodology employed in this research involved meticulous computational simulations that accounted for complex interactions of charged nuclei with cosmic backgrounds, including the cosmic microwave background radiation and extragalactic magnetic fields. The simulations considered energy loss mechanisms such as photodisintegration and nuclear decay, which impact how different nuclei propagate across cosmological distances. The key finding was that ultraheavy nuclei exhibit a slower rate of energy degradation compared to protons or intermediate nuclei, allowing them to reach Earth with energies that rival or surpass those previously considered outliers.

Understanding the composition of ultrahigh-energy cosmic rays has significant ramifications for astrophysical theory and observational strategy. If ultraheavy nuclei compose a substantial fraction of the highest-energy events, this would influence interpretations of cosmic-ray energy spectra in both the northern and southern hemispheres, potentially explaining observed anisotropies and spectral differences. Moreover, the prospect of heavier nuclei prompts reconsideration of the magnetic deflections during their intergalactic journey, affecting mapping efforts that aim to pinpoint source regions.

Future observational efforts will be crucial in testing and refining these hypotheses. Next-generation cosmic-ray observatories, including the planned AugerPrime in Argentina and the Global Cosmic Ray Observatory concept, aim to improve the precision of UHECR composition measurements. These facilities will enhance sensitivity to particle mass through advanced detection technologies, enabling discrimination between light and heavy nuclei at ultrahigh energies. By correlating composition data with arrival directions and energy spectra, these observatories could unravel the true nature and astrophysical provenance of these extraordinary cosmic rays.

The research embodies a collaborative effort spanning institutions and countries. Alongside Murase, the team included B. Theodore Zhang, who at the time was a postdoctoral researcher at Kyoto University’s Yukawa Institute for Theoretical Physics; Mukul Bhattacharya, an Eberly Postdoctoral Fellow at Penn State; and Nick Ekanger and Shunsaku Horiuchi from Virginia Tech. Their combined expertise spanned computational physics, astrophysics, and nuclear physics, facilitating a comprehensive approach to this multifaceted scientific challenge.

Contextualizing these findings within the broader cosmic panorama underlines how cosmic rays—tiny atomic nuclei born in catastrophic cosmic events—serve as natural laboratories probing extremes of physics unattainable on Earth. The journey of ultraheavy nuclei across billions of light-years and their detection here provide a unique window into processes driving the most energetic phenomena in the universe. Exploring these frontiers enhances not only astrophysical knowledge but also offers clues about fundamental particle interactions and high-energy physics under conditions far beyond terrestrial experiments.

Ultimately, the notion that ultraheavy atomic nuclei might be the protagonists behind the most energetic cosmic rays compels astrophysicists to rethink long-held assumptions. It invites a paradigm shift in the hunt for cosmic accelerators and the interpretation of the cosmic-ray sky. As observational capabilities improve and theoretical models grow more sophisticated, the clues hidden in these ultraheavy cosmic messengers may soon unravel one of modern astrophysics’ oldest and most tantalizing mysteries.

Subject of Research: Not applicable
Article Title: Ultraheavy Ultrahigh-Energy Cosmic Rays
News Publication Date: 7-May-2026
Web References: https://doi.org/10.1103/221m-gvs3
References: Physical Review Letters, 2026
Image Credits: Osaka Metropolitan University / Kyoto University L-INSIGHT / Ryuunosuke Takeshige

Keywords

Astrophysics | Ultrahigh-energy cosmic rays | Ultraheavy nuclei | Cosmic ray composition | Particle acceleration | Neutron stars | Black hole formation | Gamma-ray bursts | Computational simulation | Cosmic ray propagation | Magnetic deflection | Astroparticle physics

Cosmic rays are composed predominantly of protons, but also contain a variety of heavier nuclei such as helium, carbon, oxygen, and iron. These high-energy particles are classified by their energy levels, ranging from low (up to a few billion electron-volts) to intermediate (several billion to hundreds of billions of electron-volts), and extending into the ultra-high energy realm of thousands of billions of electron-volts and beyond. Despite intense study, the mechanisms behind their acceleration and journey through space have posed significant challenges, partly due to the limitations of terrestrial particle accelerators and observational technologies. DAMPE, launched in December 2015, is specifically designed to overcome these hurdles by operating in space, away from Earth’s atmospheric interference.

The core achievement of the DAMPE mission revolves around its detailed and precise measurement of cosmic ray nuclei energy spectra, revealing a universal “spectral softening” phenomenon at a particular rigidity threshold. Rigidity, defined as the resistance of a charged particle’s path to deflection by magnetic fields, is a critical parameter in cosmic ray physics. DAMPE’s observations demonstrate that at around 15 TV (teraelectron-volts) rigidity, the flux of cosmic ray nuclei—across the spectrum from protons to iron—experiences an enhanced rate of decline, more pronounced than previously observed. This consistent behavior across different types of nuclei decisively supports models in which cosmic ray acceleration and transport are governed by rigidity, thereby excluding alternative theories centered on energy per nucleon with extremely high confidence.

This discovery has profound implications for our understanding of both cosmic ray sources and interstellar propagation. The spectral softening suggests that particle acceleration processes in sources such as supernova remnants, pulsars, or black hole jets may be fundamentally limited by rigidity-dependent mechanisms, meaning that heavier nuclei follow similar physical laws but differ primarily because of their charge-to-mass ratio. Furthermore, it informs models of the interstellar medium’s magnetic environment, where cosmic rays diffuse and lose energy before arriving at Earth, thus offering a new lens through which to interpret galactic particle dynamics.

A key strength of the DAMPE project lies in its sophisticated technological instrumentation. The University of Geneva’s astrophysics group made crucial contributions, especially in developing the Silicon-Tungsten Tracker (STK), a sub-detector enabling the precise reconstruction of particle trajectories and accurate charge measurements. Advanced artificial intelligence algorithms were implemented to analyze the complex data stream from DAMPE, refining event reconstruction and distinguishing among particle types with unprecedented accuracy. Such innovation has not only enabled the detection of nuanced spectral features but has also set a new benchmark for cosmic ray observational capabilities.

The implications extend beyond cosmic ray physics into broader astrophysical and particle physics domains. By characterizing the universal rigidity-dependent spectral softening, DAMPE constrains theories about the nature of particle acceleration at cosmic ray sources, impacting models that attempt to link cosmic rays with dark matter signatures or exotic phenomena. As cosmic rays penetrate the galaxy, their energy-dependent journey carries rich information about magnetic turbulence, interstellar shock waves, and the interplay of galactic processes, all of which are now better accessible thanks to the new DAMPE results.

Moreover, DAMPE’s work importantly addresses the so-called “knee” of cosmic ray spectra—a well-known feature where the flux abruptly changes at energies of the order of a few petaelectron-volts (PeV). The detection of spectral softening below this knee offers a finer resolution on the transition in cosmic ray behavior, highlighting how different nuclei approach their acceleration and propagation limits. The insights garnered by DAMPE pave the way for future missions and ground-based experiments seeking to resolve the knee’s remaining puzzles and understand the highest-energy cosmic phenomena.

This breakthrough also exemplifies the increasing fondness for interdisciplinary and international collaboration in modern astrophysics. The multi-institutional partnership spanning countries and combining expertise in particle physics, astrophysics, detector technologies, and computational science has enabled DAMPE’s success. Through this synergy, new pathways open for leveraging machine learning in space-based particle detection and for integrating observational data with theoretical frameworks at a level not possible before.

Looking forward, the ongoing data analysis from DAMPE and complementary projects such as AMS-02 and the Cherenkov Telescope Array will deepen our grasp of cosmic ray origins. The universal spectral softening identified by DAMPE challenges existing models to incorporate rigidity-dependent acceleration and propagation with precise, quantitative accuracy. As these efforts continue, we anticipate transformative insights into the fundamental laws shaping the high-energy universe, potentially unveiling connections to dark matter physics or unknown aspects of interstellar medium structure.

In conclusion, the Dark Matter Particle Explorer’s revelations represent a landmark in cosmic ray research, firmly anchoring the critical role of particle rigidity in their behavior. Beyond confirming long-held theoretical ideas, DAMPE’s findings inspire fresh interpretations of cosmic phenomena, from individual particle acceleration sites to the galactic-scale distribution and interaction of energetic particles. This breakthrough, marked by precision measurement and clever instrumentation, brings us closer to decoding the cosmic messages riding the high-energy particles that ceaselessly traverse our galaxy and cosmos at large.

Subject of Research: Not applicable
Article Title: Charge-dependent spectral softenings of primary cosmic rays below the knee
News Publication Date: 29-Apr-2026
Web References: DOI: 10.1038/s41586-026-10472-0
Image Credits: © Chinese Academy of Science

Keywords

Cosmic Rays, DAMPE, Dark Matter Particle Explorer, rigidity, spectral softening, high-energy particles, cosmic ray origins, particle acceleration, astrophysics, Silicon-Tungsten Tracker, energy spectra, particle propagation

Gamma-ray binaries, celestial systems comprising a massive star paired with a compact object—either a neutron star or a stellar-mass black hole—have long fascinated astronomers due to their extreme and energetic environments. These binaries serve as natural astrophysical laboratories where particles can be accelerated to staggering energies. Until now, only a handful of such binaries have been confirmed to emit very-high-energy gamma rays, generally up to a few tens of TeV. The revelation that LS I +61° 303 can generate gamma rays an order of magnitude higher thrusts this system into uncharted territory, hinting that it functions as a site for particle acceleration at velocities previously unverified in such binaries.

LHAASO’s unique sensitivity and expansive energy detection capabilities have been instrumental in this discovery. By meticulously analyzing the gamma-ray spectrum of LS I +61° 303, scientists could extend measurements into the ultra-high-energy regime, precisely up to 200 TeV. This remarkable feat confirms LS I +61° 303 as a bona fide UHE gamma-ray binary and implies the presence of extraordinarily powerful accelerators within the system. The observatory’s high-altitude location and cutting-edge detector array enable it to capture extensive air showers produced when cosmic gamma rays strike Earth’s atmosphere, providing unparalleled insight into these energetic phenomena.

Crucially, the LHAASO collaboration uncovered that the intensity of gamma-ray emissions from LS I +61° 303 exhibits a distinctive modulation synchronized with the binary’s orbital period of approximately 26.5 days. This orbital modulation is not uniform across energies, demonstrating a complex dependence on gamma-ray energy that signals intricate internal processes governing particle acceleration and emission within the binary. Understanding this modulation enhances our comprehension of how dynamic interaction between the stellar wind of the massive star and the compact object’s environment shapes the acceleration mechanisms at play.

Recent theoretical models have struggled to explain how electrons can reach the energy levels required to generate gamma rays beyond 100 TeV in such systems. Strong magnetic fields typically induce intense synchrotron radiation losses for high-energy electrons, effectively preventing their acceleration to these daunting scales. The detection of gamma rays at energies exceeding 100 TeV thus strongly suggests a hadronic origin: high-energy protons, rather than electrons, are likely being accelerated within the system. These protons then interact with the dense stellar wind, creating ultra-high-energy gamma rays through proton-proton collisions that produce neutral pions, which decay into gamma photons.

This fascinating interpretation carries profound implications. It positions gamma-ray binaries like LS I +61° 303 as potential “PeVatrons,” astrophysical accelerators capable of propelling particles to the PeV (peta-electron-volt) regime—a milestone long sought by cosmic ray researchers. Identifying such PeVatrons is essential in unraveling the enigmatic sources of the highest-energy cosmic rays that constantly bombard Earth. These cosmic rays hold clues to the mechanisms that govern extreme particle acceleration, and confirming their astrophysical sources will unlock new chapters in high-energy astrophysics.

The detection of LS I +61° 303 as a UHE gamma-ray emitter also places stringent constraints on existing theoretical frameworks. Particle acceleration models must now account for mechanisms robust enough to overcome both magnetic energy losses and complex orbital dynamics. They must explain how protons are energized and efficiently interact with local matter to yield the observed gamma-ray flux and modulation characteristics. Moreover, these models advance the dialogue of how various binary system parameters, such as orbital eccentricity, stellar wind density, and magnetic field structure, synergize to create energetic radiation signatures observed across electromagnetic spectra.

From a broader perspective, the results achieved by the LHAASO collaboration enrich the burgeoning field of multi-messenger astronomy, which integrates information from electromagnetic signals with neutrinos, cosmic rays, and gravitational waves to paint a holistic portrait of energetic astrophysical events. The identification of hadronic processes in LS I +61° 303 aligns with expectations that such binaries could be sources of neutrinos, tantalizing prospects for coincident detections by neutrino observatories worldwide. Such cross-disciplinary investigations will deepen our grasp of extreme particle physics phenomena occurring far beyond our solar system.

The instruments and techniques deployed by LHAASO underscore the technological leaps necessary to unlock these astrophysical riddles. Located at a high elevation to maximize the detection of cosmic-ray air showers, its detectors combine a water-Cherenkov array, muon detectors, and wide-field Cherenkov telescopes, all collaboratively enhancing gamma-ray sensitivity from multi-TeV to PeV energies. This comprehensive array enables continuous monitoring of the northern sky, capturing temporal variations and extending energy reach beyond previous observatories—capabilities pivotal for characterizing the ephemeral and orbitally modulated emissions of sources like LS I +61° 303.

Historically, the pursuit of the sources of high-energy cosmic rays has been likened to a cosmic detective story, tracing particles from their Earthly detections back to their astrophysical origins. The confirmation of UHE gamma rays from LS I +61° 303 brings this quest one critical step closer to resolution. It offers a rare observational window into natural cosmic accelerators functioning at near-imaginable energy scales, inviting a re-examination of the physical conditions that can forge such extreme particle energies and trigger observable gamma-ray emissions.

As investigators delve deeper into these findings, future studies will likely focus on refining orbital modulation models, exploring multi-wavelength observational campaigns, and coordinating with neutrino and gravitational wave observatories. These efforts will help tease apart the subtle interplay between particle acceleration, radiation processes, and binary system dynamics. The LHAASO collaboration’s breakthrough thus not only illuminates a long-standing astrophysical mystery but also paves the way for innovative, interdisciplinary explorations that promise to redefine high-energy astrophysics for decades to come.

In summary, the groundbreaking detection of ultra-high-energy gamma rays from the gamma-ray binary LS I +61° 303 heralds an epochal advance in astroparticle physics. This discovery reshapes our conceptual and theoretical frameworks regarding particle acceleration mechanisms in binary systems and broadens the scope of viable cosmic ray sources. With its unique observational capabilities, LHAASO has propelled a venerable astrophysical puzzle into a new arena of discovery—one that promises thrilling scientific revelations at the intersection of cosmic rays, gamma-ray astronomy, and multi-messenger astrophysics.

Subject of Research: Ultra-high-energy gamma-ray emission from the gamma-ray binary LS I +61° 303 and its implications for particle acceleration in extreme astrophysical environments.

Article Title: Detection of Ultra-High-Energy Gamma Rays from the Gamma-ray Binary LS I +61° 303

News Publication Date: 30-Apr-2026

Web References:
Physical Review Letters DOI 10.1103/7xhp-tff7

References:
The study published in Physical Review Letters by the LHAASO collaboration and affiliated researchers from the Institute of High Energy Physics and Shanghai Astronomical Observatory of the Chinese Academy of Sciences.

Keywords:
Cosmic rays, Gamma-ray binaries, Ultra-high-energy gamma rays, Particle acceleration, PeVatrons, LS I +61° 303, LHAASO, Synchrotron radiation, Hadronic interactions, Multi-messenger astronomy, Astroparticle physics, Orbital modulation

Cosmic rays are predominantly subatomic particles such as protons and atomic nuclei, accelerated to velocities just shy of light speed. Their energy scale far exceeds what humanity’s most sophisticated accelerators can achieve, marking them as natural PeVatrons—astrophysical accelerators operating at petaelectronvolt energies. Understanding these PeVatrons is pivotal, not only because they represent some of the most extreme environments in the universe, but also because they may unlock secrets about galaxy evolution and the fabric of dark matter. Zhang’s research group focuses on identifying and deciphering the mechanics behind these extraordinary cosmic accelerators through multi-wavelength astrophysical observations.

One of the most challenging issues has been associating specific cosmic ray sources with identifiable astrophysical objects. Potential accelerators include black hole environments, supernova remnants, and expansive star-forming regions. Each of these is notable for their potential to generate not just cosmic rays, but also neutrinos—elusive, nearly massless particles that stream abundantly through space and even our own bodies. “Cosmic rays and their neutrino counterparts are intimately connected,” Zhang explains, underscoring the importance of pinning down their origins to understand broader astrophysical processes and particle interactions.

The recent breakthrough centers around the Large High Altitude Air Shower Observatory (LHAASO), which has been the vanguard in discovering sources that accelerate cosmic rays to previously unattainable energies. Among these discoveries is an enigmatic PeVatron designated 1LHAASO J0343+5254u. The mystery persisted until Zhang’s postdoctoral researcher, Stephen DiKerby, employed X-ray observations from the European Space Agency’s XMM-Newton telescope to shed light on the nature of this source. Their analysis revealed the presence of a pulsar wind nebula—a vast bubble inflated by winds of highly relativistic electrons and positrons emanating from a rapidly spinning neutron star, or pulsar. This nebula acts as a cosmic crucible, accelerating particles to extreme energies, and confirms that this particular PeVatron is indeed a pulsar wind nebula type of cosmic ray source.

Identifying a pulsar wind nebula as a definitive PeVatron marks a seminal achievement in the field. Such nebulae are powered by pulsars’ rotational energy losses and exhibit complex emission across the electromagnetic spectrum, from radio waves to gamma rays. The relativistic winds from the pulsar create shocks within the nebula, efficiently accelerating particles. This process not only explains the hard X-ray and gamma-ray signals detected but also establishes a direct link between multi-wavelength emissions and the acceleration mechanisms at work. “This is one of the few cases where the astrophysical nature of a PeVatron has been directly identified with confidence,” notes Zhang, highlighting the significance of the finding for high-energy astrophysics.

Complementing this discovery, a team of Michigan State undergraduate researchers—Ella Were, Amiri Walker, and Shaan Karim—conducted an ancillary investigation into other LHAASO-detected sources using NASA’s Swift X-ray telescope. Their focus lay in setting upper limits on X-ray emissions from less well-characterized cosmic ray accelerators. Although no definitive X-ray signatures emerged from their observations, this approach lays vital groundwork for future studies aiming to map out the diverse population of galactic PeVatrons. By establishing constraints on these sources’ high-energy environments, their work forms a strategic pathfinder, opening new lines of inquiry into the physics of particle acceleration in the Milky Way.

This dual-pronged research strategy—combining precise X-ray imaging with extensive particle observatory data—embodies the power of multi-messenger astrophysics. Cosmic rays and neutrinos are complementary probes: while cosmic rays are charged and their trajectories scrambled by magnetic fields, neutrinos travel unperturbed, pointing directly to their origins. Zhang’s team aspires to merge data from the IceCube Neutrino Observatory, which detects high-energy neutrinos deep in the Antarctic ice, with data from X-ray and gamma-ray telescopes. Through this synergy, they aim to elucidate why certain cosmic ray sources are prolific neutrino emitters while others are silent, a puzzle that could revolutionize our understanding of particle acceleration and high-energy astrophysical processes.

Moreover, such comprehensive studies bear upon fundamental questions regarding galactic ecology and the role cosmic particles play in shaping it. Cosmic rays influence the interstellar medium, triggering complex chemical reactions and potentially affecting star formation. They also have direct implications for Earth’s biosphere; for instance, as Zhang points out, approximately 100 trillion cosmic neutrinos from distant astrophysical phenomena penetrate our bodies every second—a humbling reminder of our deep connection to the cosmos. Understanding the sources and behavior of these particles is not just an academic pursuit but a piece of the cosmic puzzle that interlinks physics, astronomy, and even biology.

Methodologically, the identification of pulsar wind nebulae as cosmic ray accelerators relies extensively on detailed spectral and spatial analyses. X-ray observatories like XMM-Newton capture high-resolution images and spectra that reveal the energetic particle populations within these nebulae. The spectral signatures, particularly non-thermal power-law emissions indicative of synchrotron radiation from relativistic electrons spiraling in magnetic fields, provide compelling evidence for ongoing particle acceleration. The morphology of the nebulae, along with timing observations of the associated pulsar, further constrains models of energy injection and particle dynamics, thereby refining our theoretical frameworks.

Looking forward, Zhang’s group envisions a collaborative future that bridges traditional astronomy and high-energy particle physics. Their research highlights the necessity of joint efforts, uniting expertise in neutrino physics, X-ray and gamma-ray astronomy, and sophisticated computational modeling. By combining observational data with theoretical insights, they aspire to build a comprehensive catalogue of cosmic ray sources with detailed classifications. Such a catalogue would constitute a legacy dataset, empowering the next generation of neutrino observatories and electromagnetic telescopes to undertake even more incisive explorations into the mechanisms that energize the cosmos.

Funding for this expansive project comes from a constellation of sources, including multiple NASA observation grants and the National Science Foundation’s support for IceCube data analysis. The interdisciplinary nature of the work exemplifies the evolving landscape of astrophysical research, where institutions, agencies, and individual scientists converge to tackle problems that transcend conventional boundaries. The discoveries at Michigan State University thus not only advance cosmic ray science but also demonstrate the power of coordinated, multi-institutional research initiatives in decoding the universe’s most profound secrets.

In sum, this body of work represents a landmark advance in high-energy astrophysics, providing a much-needed link between observed cosmic phenomena and the fundamental mechanisms that accelerate particles to extreme energies. From unmasking a pulsar wind nebula as a bona fide PeVatron to paving pathways for future X-ray and neutrino studies, Zhang and her colleagues have etched a significant chapter in humanity’s quest to comprehend the high-energy universe. As these cosmic ray accelerators continue to reveal their secrets, our grasp of the dynamic and energetic processes shaping the galaxy will only deepen, promising new discoveries on the horizon.

Subject of Research: The origin and nature of galactic cosmic rays, focusing on pulsar wind nebulae as cosmic ray sources and the study of PeVatron candidates through multi-wavelength and multi-messenger observations.

Article Title: Discovery of a Pulsar Wind Nebula Candidate Associated with the Galactic PeVatron 1LHAASO J0343+5254u

News Publication Date: 2-Apr-2025

Web References:

• First paper (ApJ)
• Second paper

References:
DiKerby, Zhang, et al., The Astrophysical Journal, Vol. 983, 21 (2025)

Image Credits: XMM-Newton space telescope

Keywords

Cosmic rays, Pulsar wind nebula, PeVatron, Neutrinos, High-energy astrophysics, X-ray astronomy, Gamma-ray astronomy, Particle acceleration, LHAASO, IceCube Neutrino Observatory