GCN Alert: Messaggio GCN inviato alle 2026-07-21 12:03:47:MS260721j Most probable sky location…

{
    "alert_type": "PRELIMINARY",
    "time_created": "2026-07-21T10:03:42Z",
    "superevent_id": "MS260721j",
    "urls": {
        "gracedb": "https://gracedb.ligo.org/v2/superevents/MS260721j/view/"
    },
    "event": {
        "significant": true,
        "time": "2026-07-21T10:01:44.313Z",
        "far": 6.786496426516116e-14,
        "instruments": [
            "H1",
            "V1"
        ],
        "group": "CBC",
        "pipeline": "gstlal",
        "search": "MDC",
        "properties": {
            "HasNS": 1,
            "HasRemnant": 1,
            "HasMassGap": 0
        },
        "classification": {
            "BNS": 0.9999958799328923,
            "NSBH": 0,
            "BBH": 0,
            "Terrestrial": 4.120067107784861e-6
        },
        "skymap_filename": "bayestar.multiorder.fits,0",
        "duration": null,
        "central_frequency": null
    },
    "external_coinc": {
        "gcn_notice_id": 1468663323,
        "ivorn": "ivo://lvk.internal/SWIFT#MDC-test_event_2026-07-21T10:01:45.784Z",
        "observatory": "Swift",
        "search": "MDC",
        "time_difference": 1.47,
        "time_coincidence_far": 4.196368604676061e-18,
        "time_sky_position_coincidence_far": 1.0869121482329334e-13,
        "combined_skymap_filename": null
    }
}