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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.

Advanced Search Examples (click to copy):

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

12307 results found.

  1. GRB 080824: Fermi Gamma Ray Burst Monitor detection
  2. GRB080825C: GLAST Burst Monitor detection
  3. SGR 0501+4516: Fermi GBM (formerly GLAST Burst Monitor) observations of three exceptionally intense outbursts
  4. GRB060908: optical observations
  5. GRB 060218: rebrightening
  6. GRB990705: No Evidence for Neutrino Signal
  7. GRB990705: Intriguing Positional Coincidences

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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