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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"

24 results found.

  1. GRB 090404: millimeter detection
  2. GRB 060306: Further Analysis of SOAR and APO NIR Observations
  3. GRB 051008 Tautenburg Supernova Search
  4. GRB 051022: RTT150 optical observations
  5. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  6. GRB051022: Swift XRT measurement of jet break
  7. GRB 051022: XRT Refined Spectral and Temporal Analysis
  8. GRB 051022, refined optical astrometry
  9. Chandra Observations of GRB 051022
  10. GRB 051022 Chandra Observations scheduled
  11. GRB 051022: WSRT Radio Detection
  12. GRB 051022, mm counterpart
  13. GRB051022: host galaxy redshift
  14. GRB 051022: Swift/UVOT Upper Limits
  15. GRB051022: Radio Counterpart
  16. GRB 051022: SOAR JKs Observations
  17. Konus-Wind observation of GRB 051022
  18. GRB 051022: Magellan NIR imaging
  19. GRB 051022: Spectral Analysis Indicates That The Spectrum Is Absorbed
  20. GRB 051022, J & K-band observation
  21. GRB 051022 (=H3950): SXC Flight Localization is Valid
  22. GRB 051022: SSO40 Optical Observations
  23. GRB051022 (=H3590), A GRB Detected By HETE
  24. GRB 051022: Optical observations

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