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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"

20 results found.

  1. GRB 071028B Swift-BAT detection of a burst
  2. GRB 070406: Swift XRT refined analysis
  3. GRB 070406: "Star" in XRT error circle S2 is an AGN?
  4. GRB 070406: Swift XRT team further analysis
  5. GRB 070406: Astrometrically Refined XRT Position, Unfading Source
  6. GRB 070406: Bright galaxy in XRT error circle is a quasar
  7. GRB 070406, Swift-BAT refined analysis
  8. GRB 070406: Correction to the optical candidate in GCN6253
  9. GRB 070406: Gemini South Imaging and XRT analysis
  10. GRB070406: Swift UVOT observations
  11. GRB 070406: further analysis of NOT images.
  12. Short GRB 070406 - Possible Bright Host Galaxy
  13. GRB 070406: Swift XRT Team analysis - Possible X-ray counterpart
  14. GRB 070406: NOT observations
  15. GRB 070406: Optical candidate
  16. GRB 070406: The exprosure time of Xinglong TNT optical Upper Limit
  17. GRB 070406: SARA upper limit
  18. GRB 070406: Xinglong TNT optical Upper Limit
  19. GRB 070406: photo-z of a bright galaxy in BAT error circle
  20. GRB 070406: Swift detection of a burst

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Download all Circulars as a .tar.gz archive:
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