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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"

17 results found.

  1. GRB 221120A: Detection by VZLUSAT-2
  2. GRB 221120A: TURBO Optical Upper Limit
  3. GRB 221120A: VIRT Optical Upper Limit
  4. GRB 221120A: GTC Confirmation of an Underlying Galaxy
  5. GRB 221120A: Swift-BAT refined analysis
  6. GRB 221120A: AKO Telescope Upper Limits
  7. GRB221120A: WIRC near-IR imaging of the afterglow candidate
  8. GRB 221120A: Liverpool Telescope Upper Limits
  9. GRB 221120A: Archival PS1 Imaging of Faint Source near XRT position
  10. GRB 221120A: Fermi GBM observation
  11. GRB 221120A: Swift-XRT refined Analysis
  12. GRB 221120A: Enhanced Swift-XRT position
  13. GRB 221120A is a short burst
  14. GRB 221120A: Swift/UVOT Upper Limits
  15. GRB 221120A: LDT Optical Afterglow Candidate
  16. GRB 221120A: GIT upper limits on optical afterglow
  17. GRB 221120A: Swift detection of a likely short burst

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