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      "id": "pin",
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        "name": "Pin cell",
        "description": "A fuel cylinder in a reflective moderator cell with two-group eigenvalue transport.",
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          0.63,
          0.63
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          {
            "id": "pin-1",
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          {
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          {
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          },
          {
            "id": "pin-4",
            "name": "Fuel pin 5",
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          },
          {
            "id": "pin-5",
            "name": "Fuel pin 6",
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-6",
            "name": "Fuel pin 7",
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          {
            "id": "pin-7",
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                "sense": "inside"
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          },
          {
            "id": "pin-8",
            "name": "Fuel pin 9",
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                  "halfHeight": 5
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-9",
            "name": "Fuel pin 10",
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-10",
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            ]
          },
          {
            "id": "pin-11",
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          },
          {
            "id": "pin-12",
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            ]
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          {
            "id": "pin-13",
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          {
            "id": "pin-17",
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            ]
          },
          {
            "id": "pin-18",
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            ]
          },
          {
            "id": "pin-19",
            "name": "Fuel pin 20",
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-20",
            "name": "Fuel pin 21",
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          },
          {
            "id": "pin-21",
            "name": "Fuel pin 22",
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-22",
            "name": "Fuel pin 23",
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-23",
            "name": "Fuel pin 24",
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            "surfaces": [
              {
                "primitive": {
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-24",
            "name": "Fuel pin 25",
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            "surfaces": [
              {
                "primitive": {
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                  "halfHeight": 5
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-25",
            "name": "Fuel pin 26",
            "material": 0,
            "surfaces": [
              {
                "primitive": {
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                  "center": [
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                  "radius": 0.42,
                  "halfHeight": 5
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-26",
            "name": "Fuel pin 27",
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            "surfaces": [
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                "primitive": {
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-27",
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-28",
            "name": "Fuel pin 29",
            "material": 0,
            "surfaces": [
              {
                "primitive": {
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                  "center": [
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-29",
            "name": "Fuel pin 30",
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            "surfaces": [
              {
                "primitive": {
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                  "center": [
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-30",
            "name": "Fuel pin 31",
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            "surfaces": [
              {
                "primitive": {
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-31",
            "name": "Fuel pin 32",
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            "surfaces": [
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          },
          {
            "id": "pin-32",
            "name": "Fuel pin 33",
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              {
                "primitive": {
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            ]
          },
          {
            "id": "pin-33",
            "name": "Fuel pin 34",
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              {
                "primitive": {
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                "sense": "inside"
              }
            ]
          },
          {
            "id": "pin-34",
            "name": "Fuel pin 35",
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              {
                "primitive": {
                  "kind": "cylinder",
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-35",
            "name": "Fuel pin 36",
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              {
                "primitive": {
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-36",
            "name": "Fuel pin 37",
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              {
                "primitive": {
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                    -2.52,
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-37",
            "name": "Fuel pin 38",
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              {
                "primitive": {
                  "kind": "cylinder",
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                    -1.26,
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-38",
            "name": "Fuel pin 39",
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              {
                "primitive": {
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            ]
          },
          {
            "id": "pin-39",
            "name": "Fuel pin 40",
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              {
                "primitive": {
                  "kind": "cylinder",
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                    1.26,
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-40",
            "name": "Fuel pin 41",
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              {
                "primitive": {
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-41",
            "name": "Fuel pin 42",
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              {
                "primitive": {
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-42",
            "name": "Fuel pin 43",
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              {
                "primitive": {
                  "kind": "cylinder",
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-43",
            "name": "Fuel pin 44",
            "material": 0,
            "surfaces": [
              {
                "primitive": {
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-44",
            "name": "Fuel pin 45",
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                "primitive": {
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            ]
          },
          {
            "id": "pin-45",
            "name": "Fuel pin 46",
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              {
                "primitive": {
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-46",
            "name": "Fuel pin 47",
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              {
                "primitive": {
                  "kind": "cylinder",
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-47",
            "name": "Fuel pin 48",
            "material": 0,
            "surfaces": [
              {
                "primitive": {
                  "kind": "cylinder",
                  "center": [
                    2.52,
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                  "radius": 0.42,
                  "halfHeight": 5
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                "sense": "inside"
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            ]
          },
          {
            "id": "pin-48",
            "name": "Fuel pin 49",
            "material": 0,
            "surfaces": [
              {
                "primitive": {
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            ]
          }
        ],
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          },
          {
            "name": "Moderator · two-group model",
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          {
            "name": "Absorber · two-group model",
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            ],
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          },
          {
            "name": "Vacuum",
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              0,
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            "fission": [
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              [
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                1
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            ],
            "chi": [
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            "color": [
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          }
        ],
        "ceMaterials": [],
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        "source": {
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          "half": [
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        },
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    },
    {
      "id": "shielding",
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        "mode": "fixed",
        "energyMode": "mg",
        "world": [
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          4,
          4
        ],
        "boundary": "vacuum",
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                    4
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                },
                "sense": "inside"
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            ]
          },
          {
            "id": "absorber-layer",
            "name": "Absorber layer",
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            ]
          }
        ],
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            ],
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          },
          {
            "name": "Moderator · two-group model",
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              [
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            ],
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          },
          {
            "name": "Absorber · two-group model",
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              [
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            ],
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            "name": "Vacuum",
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            ],
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        ],
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        "source": {
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          "group": 0,
          "direction": [
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        },
        "histories": 4096,
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    },
    {
      "id": "hydrogen",
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        "energyMode": "ce",
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            ]
          }
        ],
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        "ceMaterials": [
          {
            "name": "Hydrogen · 0 K",
            "dataset": "h1-endfb8-0k",
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            "temperatureK": 0,
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        ],
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          "group": 0
        },
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}