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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').

4 results found.

  1. LIGO/Virgo/KAGRA S240825ar: Upper limits from Swift/BAT-GUANO
  2. LIGO/Virgo/KAGRA S240825ar: Updated Sky localization
  3. LIGO/Virgo/KAGRA S240825ar: Updated Sky localization
  4. LIGO/Virgo/KAGRA S240825ar: Identification of a GW compact binary merger candidate

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Download all Circulars as a .tar.gz archive:
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