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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 250916A: Swift/UVOT Detection
  2. GRB 250916A: CrAO ZTSh R-band optical observations
  3. GRB 250916A: SAO RAS Zeiss-1000 optical observations
  4. GRB 250916A: FTW optical and NIR observations of the counterpart
  5. GRB 250916A: Mondy R-band optical observations
  6. GRB 250916A: Fermi GBM Observation
  7. GRB 250916A: KAIT optical observations
  8. GRB 250916A: NuSTAR detection of the prompt emission
  9. GRB 250916A: further SAO RAS optical observations
  10. GRB 250916A: OSIRIS+/GTC redshift z = 2.015
  11. GRB 250916A: Swift-XRT observations
  12. GRB 250916A: MAO/AZT-22 optical observations
  13. GRB 250916A: SAO RAS optical observations
  14. GRB 250916A : GIT optical observations
  15. GRB 250916A: Glowbug gamma-ray detection
  16. GRB 250916A: Swift ToO observations
  17. GRB 250916A: GOTO optical counterpart candidate
  18. GRB 250916A: AstroSat CZTI detection of a bright long burst
  19. Fermi GRB 250916A: Global MASTER-Net observations report
  20. GRB 250916A: Fermi GBM Final Real-time Localization

Advanced

Download all Circulars as a .tar.gz archive:
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