China’s Dark Matter Particle Explorer recorded more than 18 billion particle events by the end of 2025, according to a new ten-year mission review. The spacecraft, known as DAMPE or Wukong, has operated since its December 17, 2015 launch and continues to measure energetic particles arriving from space.
The review by Jian-Hua Guo and four colleagues was posted on arXiv on October 15, 2026, and revised on October 17. Listed as accepted by Astronomy Communications, it brings together instrument performance and previously published results on electrons, atomic nuclei, and gamma rays. Its findings describe a decade of measurements, rather than a new detection of dark matter.
How the Detectors Measure Particles
DAMPE’s four detector systems measure complementary properties of incoming particles. A plastic scintillator measures electric charge and helps distinguish charged particles from gamma rays. A silicon-tungsten tracker reconstructs trajectories; tungsten layers allow incoming photons to convert into electron-positron pairs that the tracker can detect.
The thick bismuth germanate calorimeter measures the energy deposited as particles produce showers of secondary particles. Its shower measurements help distinguish electrons from protons. A neutron detector supplies additional information for separating these events. Combining these measurements allows researchers to identify particle populations and reconstruct how their abundance changes with energy.
A spectrum is a count of particles distributed by energy. DAMPE’s electron-plus-positron spectrum shows a break near 0.9 teraelectronvolts, or about 900 billion electronvolts. Above such a break, the rate at which particle abundance changes with energy differs from the rate below it. The review reports a statistical significance of approximately 6.6 standard deviations for this feature and notes corroboration from later AMS-02 and CALET measurements.
The mission also measures atomic nuclei. Its boron observations extend from 10 gigaelectronvolts per nucleon to eight teraelectronvolts per nucleon. Expressing energy per nucleon accounts for the particles within an atomic nucleus. The boron spectrum becomes less steep near 200 gigaelectronvolts per nucleon, a feature reported at eight standard deviations. Such measurements help test explanations of cosmic-ray transport through the Galaxy.
What the Dark Matter Search Found
Dark matter research uses a different signature. Gravitational observations establish the motivation for searching for an unseen matter component, as explained in New Space Economy’s cosmology overview. DAMPE tests whether processes involving hypothetical dark matter particles produce detectable gamma rays.
A search using the mission’s first five years of observations examined gamma-ray lines between 10 and 300 gigaelectronvolts. A line would appear as an excess concentrated around a particular energy. The analysis found no line signal or candidate meeting its stated threshold. It instead constrained particular annihilation and decay models.
The authors report that analyses extending the electron-plus-positron spectrum toward 10 teraelectronvolts are continuing. Joint work with the ground-based Large High Altitude Air Shower Observatory is also underway to connect measurements of cosmic-ray protons across a larger energy interval.
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