GCN Alert: Messaggio GCN inviato alle 2025-12-20 04:03:54:MS251220d Most probable sky location…

{
    "alert_type": "PRELIMINARY",
    "time_created": "2025-12-20T03:03:45Z",
    "superevent_id": "MS251220d",
    "urls": {
        "gracedb": "https://gracedb.ligo.org/superevents/MS251220d/view/"
    },
    "event": {
        "significant": true,
        "time": "2025-12-20T03:03:09.451Z",
        "far": 5.176954877338635e-16,
        "instruments": [
            "H1",
            "L1",
            "V1"
        ],
        "group": "CBC",
        "pipeline": "gstlal",
        "search": "MDC",
        "properties": {
            "HasNS": 1,
            "HasRemnant": 1,
            "HasMassGap": 0
        },
        "classification": {
            "BNS": 0.9999998181083839,
            "NSBH": 0,
            "BBH": 0,
            "Terrestrial": 1.8189161610090667e-7
        },
        "duration": null,
        "central_frequency": null
    },
    "external_coinc": null
}