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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"

23 results found.

  1. GRB 220514A: KAIT Optical Afterglow Confirmation
  2. GRB 220408A: HCT optical upper limit
  3. GRB 220408A: GRANDMA observations
  4. GRB 220408A: Lowell Discovery Telescope Optical Observations
  5. GRB 220408A: Swift-BAT refined analysis
  6. GRB 220408A: RATIR Optical and NIR Observations
  7. GRB 220408A: 1.3m DFOT Optical upper limit
  8. GRB 220408A: LOAO, DOAO, and, SAO optical upper limit
  9. GRB 220408A: redshift lower limit estimating
  10. GRB 220408A: NOT optical observations and archival detection
  11. GRB 220408A: LCO Optical Afterglow Detection
  12. GRB 220408A: Swift-XRT refined Analysis
  13. GRB 220408A: BOOTES-5/JGT optical afterglow detection
  14. GRB 220408A: GIT optical upper limit
  15. GRB 220408A: Fermi GBM observation
  16. GRB 220408A: Swift/UVOT Detection
  17. GRB 220408A: Xinglong-2.16m optical upper limit
  18. GRB 220408A: Enhanced Swift-XRT position
  19. Chandra upper limit at the location of GRB 220408A
  20. GRB 220408A: KAIT Optical Observations
  21. Fermi GRB 220408A: Global MASTER-Net observations report
  22. GRB 220408A: Swift detection of a burst with an optical counterpart, possibly associated with M51
  23. GRB 220408A: Fermi GBM Final Real-time Localization

Advanced

Download all Circulars as a .tar.gz archive:
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