Task: Text Categorization
Input (English): The ISIS and SNS facilities produce these particles using spallation, and a nonzero electric dipole moment would imply the violation of CPT theorem. Certain objects composed of these particles obey the Tolman-Oppeheimer-Volkov limit, whose antiparticle having a mass of 940 MeV was discovered by Bruce Cork. When free, this particle has a lifetime of about 15 minutes and decays into an antineutrino, an electron and a proton, and it is a baryon made up of two down quarks and one up quark. Discovered by James Chadwick, for 10 points, identify this neutral subatomic particle.
Output (English): Science