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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"

20 results found.

  1. GRB 250207a: ATCA Radio Upper Limits
  2. IceCube-250207A: MASTER flaring blazar QSOJ0854+2006 with Zhirkov effect
  3. GRB 250207A: Fermi GBM Observation
  4. IceCube-250207A: One candidate from the Zwicky Transient Facility
  5. Konus-Wind detection of GRB 250207A
  6. GRB 250207A: Skynet optical afterglow observations
  7. IceCube-250207A: Upper limits from a search for additional neutrino events in IceCube
  8. Fermi-LAT Gamma-ray Observations of IceCube-250207A
  9. GRB 250207A: 1.3m DFOT Optical observations
  10. GRB 250207A: Swift-BAT refined analysis
  11. GRB 250207A: Swift-XRT refined Analysis
  12. GRB 250207A: Enhanced Swift-XRT position
  13. GRB 250207A: REM IR afterglow detection
  14. GRB 250207A: FRAM-Auger optical detection
  15. IceCube-250207A - IceCube observation of a high-energy neutrino candidate track-like event
  16. GRB 250207A: REM optical afterglow detection
  17. GRB 250207A: Swift/UVOT Detection
  18. GRB 250207A: COLIBRÍ/DDRAGO Optical Afterglow Detection
  19. GRB 250207A: Swift detection of a burst with optical counterpart
  20. GRB 250207A: Fermi GBM Final Real-time Localization

Advanced

Download all Circulars as a .tar.gz archive:
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