"β-particle" meaning in English

{
  "forms": [
    {
      "form": "β-particles",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "β-particle (plural β-particles)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
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          "source": "w"
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          "parents": [
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        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Radioactivity",
          "orig": "en:Radioactivity",
          "parents": [
            "Nuclear physics",
            "Radiation",
            "Physics",
            "Quantum mechanics",
            "Energy",
            "Sciences",
            "Nature",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "beta particle"
      ],
      "id": "en-β-particle-en-noun-8vByhYTx",
      "links": [
        [
          "beta particle",
          "beta particle"
        ]
      ]
    }
  ],
  "word": "β-particle"
}

{
  "forms": [
    {
      "form": "β-particles",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "β-particle (plural β-particles)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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        "English countable nouns",
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        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms spelled with Β",
        "English terms with non-redundant non-automated sortkeys",
        "English terms written in multiple scripts",
        "en:Radioactivity"
      ],
      "glosses": [
        "beta particle"
      ],
      "links": [
        [
          "beta particle",
          "beta particle"
        ]
      ]
    }
  ],
  "word": "β-particle"
}