GCN Alert: Messaggio GCN inviato alle 2026-03-21 12:07:13:

{
    "alert_type": "RETRACTION",
    "time_created": "2026-03-21T11:07:13Z",
    "superevent_id": "MS260321k",
    "urls": {
        "gracedb": "https://gracedb.ligo.org/superevents/MS260321k/view/"
    },
    "event": null,
    "external_coinc": null
}