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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

5 results found.

  1. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  2. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  3. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  4. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  5. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate

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Download all Circulars as a .tar.gz archive:
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