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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"

22112 results found.

  1. GRB971227: Plaskett R-band observations
  2. GRB 971227: Optical clarifications
  3. GRB971227: Further CAHA R-band images
  4. GRB971227: LOTIS observations
  5. GRB971214: Optical Observations and Calibrations
  6. Sub-millimeter Observations of GRB 971214 at the JCMT
  7. GRB 971214: EUVE Observations
  8. GRB 971214: KPNO Optical Observations
  9. GRB 971214: Optical Observations
  10. Radio Observations of GRB 971214 at the VLA
  11. GRB 971024: KPNO Optical Observations
  12. GRB 970828: Palomar Observations

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Download all Circulars as a .tar.gz archive:
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