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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"

28717 results found.

  1. GRB980326 optical observations
  2. GRB970508 SAO RAS optical observations
  3. GRB 971214: Redshift from Keck Observations
  4. Near-IR follow-up on GRB 971227
  5. GRB971214: Keck R & I-band Observations
  6. GRB 971227: Optical Observations
  7. Optical Observations of the GRB 971227 field
  8. GRB971227: Plaskett R-band observations
  9. GRB 971227: Optical clarifications
  10. GRB971227: LOTIS observations
  11. GRB971214: Optical Observations and Calibrations
  12. Optical Observations of GRB 971214 at Keck
  13. GRB 971024: Refined analysis by USNOFS Observations
  14. GRB 971024: USNO Observations
  15. GRB 970925: BATSE Localization
  16. IRAS 18119-1342 and the possible new SGR
  17. GRB 970228: Keck/LRIS Optical Observations

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