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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"

23 results found.

  1. GRB 220521A: ATCA detection
  2. GRB 220521A: ALMA detection
  3. GRB 220521A: BOOTES-2/TELMA and CAHA 2.2m telescope optical upper limit
  4. GRB 220521A: classification and detection by SPI-ACS/INTEGRAL
  5. GRB 220521A: ISON-Castelgrande observatory optical observations
  6. GRB 220521A: MITSuME Akeno optical upper limits
  7. GRB 220521A: Gemini Observations
  8. GRB 220521A: MMT Afterglow Imaging
  9. GRB 220521A: REM optical/NIR upper limits
  10. GRB 220521A: LCO Optical Detection
  11. GRB 220521A: Swift-BAT refined analysis
  12. GRB 220521A: Fermi GBM detection
  13. GRB 220521A: Sintesz-Newton/CrAO optical upper limit
  14. GRB 220521A: RATIR Optical and NIR Observations
  15. GRB 220521A: Swift-XRT refined Analysis
  16. GRB 220521A: Swift/UVOT Upper Limits
  17. GRB 220521A: SAO RAS optical observations
  18. GRB 220521A: Enhanced Swift-XRT position
  19. GRB 220521A: NOT spectroscopic redshift
  20. GRB 220521A: NOT optical afterglow detection
  21. GRB 220521A: Prompt enhanced Swift-XRT position
  22. GRB 220521A: Swift detection of a burst
  23. GRB 220521A: Fermi GBM Final Real-time Localization

Advanced

Download all Circulars as a .tar.gz archive:
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