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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"

21820 results found.

  1. GRB980329 optical observations
  2. GRB980326 optical observations
  3. GRB980326 optical observations
  4. GRB980326 optical observations
  5. Optical Observations of GRB 970508
  6. Near-IR follow-up on GRB 971227
  7. Optical Observations of the GRB 971227 field
  8. Optical Observations on GRB 971227
  9. GRB971227: Plaskett R-band observations
  10. GRB 971227: Optical clarifications
  11. GRB971227: Further CAHA R-band images
  12. GRB971227: LOTIS observations
  13. GRB971214: Optical Observations and Calibrations
  14. Sub-millimeter Observations of GRB 971214 at the JCMT
  15. GRB 971214: EUVE Observations
  16. GRB 971214: KPNO Optical Observations
  17. GRB 971214: Optical Observations
  18. Radio Observations of GRB 971214 at the VLA
  19. GRB 971024: KPNO Optical Observations
  20. GRB 970828: Palomar Observations

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Download all Circulars as a .tar.gz archive:
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