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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

7 results found.

  1. Radio observations of GRB 110428A with the EVLA
  2. GRB 110428A: Fermi-GBM observation
  3. GRB 110428A : X-ray afterglow confirmation
  4. GRB 110428A: Suzaku WAM observation of the prompt emission
  5. GRB 110428A : Swift-XRT observations
  6. Konus-Wind observation of GRB 110428A
  7. GRB 110428A: Fermi-LAT Detection

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Download all Circulars as a .tar.gz archive:
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