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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

321 results found.

  1. GRB041220: Swift-BAT burst
  2. Swift-BAT detection of the bright long burst GRB041219
  3. GRB 041219 - A long GRB detected by INTEGRAL
  4. XMM-Newton Images of GRB 040827
  5. XRF040701: Second-Epoch Chandra Observations
  6. XRF040701: First-Epoch Chandra Observations
  7. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  8. GRBlog: Compilation of all GCN Circ. data
  9. IPN detection of renewed activity from SGR1806-20
  10. IPN triangulation of GRB030131 - CORRECTION
  11. IPN triangulation of GRB021119 (annulus)
  12. IPN triangulation of GRB021025 (annulus)
  13. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  14. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  15. AXP 1E2259+586: quasi-simultaneous optical observation
  16. AXP 1E2259+586 optical observations
  17. SGR-like Bursts from the AXP 1E 2259+586
  18. IPN triangulation of GRB020525
  19. SGR 1900+14, Chandra observations
  20. IPN triangulation of GRB 001004
  21. GRB 991216--Summary of RXTE Observations

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Download all Circulars as a .tar.gz archive:
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