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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').

6 results found.

  1. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  2. GW S240915b and S240919bn : Swift UVOT follow-up
  3. LIGO/Virgo S240919bn: GOTO optical upper limits
  4. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  5. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  6. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate

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Download all Circulars as a .tar.gz archive:
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A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

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